Spatial ecosystem modelling of the upper Gulf of California using Atlantis (poster, Thursday afternoon)
Cameron Ainsworth (NOAA Northwest Fisheries Science Center, Seattle, Washington)
In collaboration with Mexican partners and US universities, NOAA is constructing a spatially explicit biogeochemical food-web model of the upper Gulf of California (Sea of Cortez) using the Atlantis modelling framework. The purpose of the study is to simulate and test various ecosystem-based management (EBM) strategies for the upper Gulf to determine likely impacts on artisanal fisheries and conservation of marine resources, including rare and endemic species. We will also examine the influence of flow from the highly regulated Colorado River in structuring habitat and driving ecosystem dynamics with the aid of a coupled regional ocean model system (ROMS model). Numerous field studies are underway to provide original data for the Atlantis model. Efforts include trawl sampling, reef diving transects, stomach content analysis, otolith microchemistry, and community interviews. Other supporting studies include reconstruction of catch trends from port records and fishery log books, and reconstruction of biomass trends from local ecological knowledge interpreted using a fuzzy logic approach. A new spatial biomass allocation algorithm based on substrate, habitat affinities and other factors increases the applicability of transect data. Spatial data on fisher behaviour will challenge fleet-effort prediction algorithms. Recommendations from this project will influence regional EBM plans and species-specific management plans to be adopted by Mexican fishery authorities in the 2010-2012 time frame.
Spatial processes in the dynamics of a harvested scallop population—a macroscopic inquiry combining remote-sensed images and fishery surveys (YI poster, Wednesday afternoon)
Ricardo Amoroso (Centro Nacional Patagónico, Chubut, Argentina)
The tehuelche scallop (Aequipecten tehuelchus) supports the main shellfisheries operating in San Jose Gulf (SJG) and San Matias Gulf (SMG), north Patagonia (Argentina). SJG, a small, semi-enclosed basin has contributed most of the regional shellfish catch since the mid 1970s. The SJG scallop stock has a strong and recurrent spatial structure: main fishing beds have been located in the east half of the gulf, where growth rates show a strong cline, decreasing clockwise from the gulf’s mouth. Connectivity and persistent geographic variation in life-history parameters are probably environmentally-driven, but oceanographic information is fragmentary and unavailable at a scale suitable for ecological analysis. I combined remote-sensed images and information from scallop surveys to identify recurrent patterns in the circulation and population dynamics, and from those infer medium-large scale spatial processes. Three main hydrographic features were revealed: influx of nutrient-rich water from the continental shelf, a frontal system splitting the gulf into two domains (east and west) with distinct hydrographic regimes, and vortex dipoles self-propagating from SJG to SMG. A composite hypothesis is advanced: (1) high scallop productivity of the comparatively small SJG is the result of nutrient-rich water being trapped, and larvae retained, east of the front, (2) self-propagating vortex dipoles provide a mechanism of asymmetric connectivity between the persistent SJG and the spasmodic SMG stocks, (3) clinal variation in growth rate within SJG reflects the inferred circulation and nutrient-extinction patterns. The spatial dynamics of the scallop stocks is relevant for designing spatially-explicit harvest strategies and for the regional integration of management.
Just the FACTs (cooperative acoustic telemetry on Florida’s East Coast) (poster, Wednesday afternoon)
Erick R. Ault, Steven Hitt, Shauna Sharpe, and Grant Stoecklin (Florida Fish & Wildlife Conservation Commission, Tequesta)
The Florida Atlantic Coast Telemetry Array (F.A.C.T.) is a regional coordination of multiple acoustic telemetry projects aimed at tracking the movement patterns of numerous species within and between ecosystems. The array is comprised of two portions: the northern array in the Mosquito/Indian River Lagoons, and the southern array of St. Lucie and Loxahatchee estuaries and adjacent reefs. Currently, FWC is engaged in two projects that comprise a large portion of the southern array. The focus of these projects is to develop a better understanding of the life history and populations dynamics for gray snapper (Lutjanus griseus), and common snook (Centropomus undecimalis). The gray snapper data collection phase is being finalized and preliminary data analysis suggests that diel movement patterns are expressed, among adult gray snappers, at individual stations within the offshore array. Previous research involving common snook has evolved into a study designed to gather data on fish movement within the St. Lucie estuary. Additionally, the cessation of the gray snapper project has provided an opportunity to conduct a broad-scale study, linking four major estuaries on the east coast with adjacent offshore structures. From this collaboration a more detailed understanding of the spatial distribution and connectivity between estuarine and offshore common snook populations can be realized.
Maps as decision-support tools for managing fish habitat and biodiversity: a foundation or barrier for common understanding (invited talk, Wednesday morning)
Peter Auster (University of Connecticut at Avery Point, Groton).
Maps serve as an important foundation for decision-making regarding management of fisheries in relation to conservation of habitat and biological diversity. Ecological attributes of the environment, represented in a geo-spatial context, enable a social process that clarifies and perhaps expands the range of options available to decision-makers and the public when faced with evaluating the trade-offs involved in alternative management actions. Representation of empirical measurements (e.g., CPUE, sediment type, community composition) and derived values (e.g., physiographic complexity derived from bathymetry, species diversity) are best applied in the management arena with acknowledgement of underlying ecological assumptions (theory) and relationships (proxies) as well as issues related to scale (both spatial and temporal) and interpolation from point data. A lexicon of attributes understood by all stakeholders is critical for productive interactions. Case studies related to development and use of map products will illustrate problems and solutions for issues identified above.
Using marine protected area monitoring data to derive metrics for fisheries management (contributed talk, Thursday morning)
Elizabeth A. Babcock (University of Miami, Florida)
No-take marine reserves can potentially be used as a proxy for unfished conditions, so that comparisons of fish abundance and size inside versus outside marine reserves can be used to calculate fishing mortality rates and other metrics useful for fisheries management. Such fishery independent metrics could be a used to confirm the results of traditional stock assessments, or used directly for fishery management. The advantages of this approach include the ability to manage at a finer spatial scale than traditional stock assessment, provided that an adequate network of well monitored marine reserves exists. There are potential pitfalls if the reserves are not a good proxy for unfished conditions, for example because migratory behavior, larval dispersal or the nature of density dependence are not correctly understood, or because the spatial distribution of fishing effort influences the monitoring data in unexpected ways. These issues were evaluated with a simulation model based on the California nearshore fishery and the newly established network of marine protected areas (many of which are no take reserves) in the Channel Islands and the central California coast. The model was based on the biology and fisheries for blue, black, darkblotched and vermillion rockfish, as well as cabezon, and was used to evaluate the implications of a range of models of recruitment spatial structure, adult movement and fishing effort reallocation in terms of the efficacy MPA based management metrics for fishery management.
Matching governance and ecology: linkages and multi-level systems (invited talk, Tuesday morning)
Fikret Berkes (University of Manitoba, Winnipeg)
The consideration of the spatial scale of ecosystems is important to manage marine resources. Both ecological systems and social systems are hierarchical; both function at several different levels. However, governance systems are not often designed to match ecosystem boundaries. Rarely is there a “fit” between the scale of ecosystems and governance systems, and gross misfit of the two scales is one of the fundamental reasons why management often fails. However, seeking a close fit between the two scales is often not realistic because both fish stocks and fishers are mobile. Fisheries exploit multiple stocks and some of these stocks may be local while others are migratory and even transboundary. Conventional stock management approaches do not often do a good job regarding these complexities. One component of an alternative approach is to start with the idea of linked social-ecological systems, ecosystem-based management that explicitly includes humans in the system, and recognizes the linked and interdependent nature of social and ecological systems. A second component of an alternative approach is to recognize the multi-level nature of governance. Bob Johannes sensitized us to the concept of marine tenure at the community level. Such local-level management is a necessary condition to provide the right incentives for stewardship behaviour; however, it is not a sufficient condition because local management does not operate in isolation. Using the example of “roving bandits,” I discuss why marine resources need to be managed simultaneously at multiple levels, and the importance of linkages for building multi-level governance systems.
Identifying meso-scale spatial patterns from fishing vessel trajectories (YI poster, Wednesday morning)
E. Bogazzi, A. M. Parma, and J. M. Orensanz (Centro Nacional Patagónico (CENPAT-CONICET), Puerto Madryn, Argentina)
The growing availability of positional data through vessel monitoring systems and observer programs creates opportunities to capture the fishing process at an appropriate spatial scale. This is essential for the analysis of exploitation and depletion of sedentary resources, where vessel movements may result in hyper-stable catch rates, and depletion may not be apparent unless one zooms in. Decisions about where to fish involve the identification of promising fishing destinations or "fishing opportunities" (FO) from two kinds of fishing operations: exploration and effective fishing. In highly aggregated stocks typical of sedentary species, FOs appear as relatively small and intensely fished areas. We explored alternative methodologies for the identification and mapping of FOs from the analysis of individual vessel trajectories using the Patagonian scallop off-shore trawl fishery (Argentina) as a study case. Distance between tows (nearest neighbor methods), cluster analysis and tortuosity of vessel trajectories allowed discrimination of exploratory tows from effective fishing events. The intensity function of effective fishing tows was then used to map the spatial distribution of FOs. Analyses of catch rates within individual FOs indicated that even at that small scale (in the order of 5 nm) depletion was not always detectable. A “stitching” pattern of hardly overlapping tows was observed when zooming into the FOs. Modern positioning technology used by industrial vessels is imposing ever more serious limitations on the use of catch rates for the analysis of abundance of sedentary stocks.
Space, place, and boundary-making in fisheries management (contributed talk, Tuesday afternoon)
Jennifer F. Brewer (East Carolina University, Greenville)
Most administrative models for fisheries management require discrete boundaries of fished resources and/or resource user groups. Such requirements conflict with empirical findings on heterogeneity and boundary-making practices published in cultural and political ecology literatures. The codification of discrete boundaries can not only increase stewardship incentives by internalizing externalities and lengthening decision horizons, but can also encourage capitalization and entrench political power, with corresponding stewardship disincentives. For these reasons and others, spatial parameters may be necessary but insufficient for socio-ecological resilience.
Optimal management solutions would permit flexible boundaries like those observed in customary adaptations to social and ecological complexity. Difficulties encountered in practical administration by the modern state, however, require alternative proposals. Policy solutions may therefore require iterations of spatio-temporal delimitation. Further, hierarchical and multi-scalar jurisdictions, though inelegant and labor-intensive, can augment transparency, accountability and compliance.
Supporting evidence is provided from both fisheries and terrestrial resource management cases, from North America and other continents. Observations suggest that scales of management can only match the scales at which the ecosystem and social systems operate if such management scales are multiple and multi-dimensional. Limits to spatial zoning efforts, and to local capacities for self-management, are also indicated. Nonetheless, pragmatic initiatives in spatially explicit management remain very promising.
Assessing and managing the benthic impacts of tropical trawling (contributed talk, Thursday morning)
Rodrigo Bustamante, Cathy Dichmont, Shane Griffiths, Nick Ellis, and Wayne Rochester (CSIRO Marine & Atmospheric Research, Australia)
A spatially explicit ecosystem management approach for the Northern Prawn Fishery (NPF) will consider the following: the target stocks; the economic and social context; indirect effects on the ecosystem; and the direct effects on ecological processes, on bycatch, and on the benthos. We assessed the spatially -explicit benthic impacts on the soft-sediment communities (fishes and epibenthic and infaunal invertebrates) influenced by the trawling disturbance of the NPF. We conducted a quantitative survey across contrasting fishing regions within the Gulf of Carpentarias spatial and historical trawling footprint. These results together with the historical data were then incorporated into the development of three modelling approaches; (i) a biophysical species distribution model, (ii) a food web mass-balance model, and (ii) a trawl simulation model. These models where then used in a management strategy evaluation (MSE) framework to evaluate a range of management scenarios aimed to inform the likely spatial management of benthic impacts. As with other similar studies, our results showed clear spatial structure of the benthic ecosystems, but their expected benthic impacts remained elusive to demonstrate unambiguously. Regional differences explained most of the variability, while only the epibenthic macro invertebrates were weakly influenced by trawl intensity. Infaunal invertebrates and demersal fish mostly varied among different regions and between day and night sampling, respectively. We have introduced the recent advances of modelling and management approaches supported by sound ecological information to evaluate alternative management strategy scenarios for the complex spatially heterogeneous effects of prawn trawling on tropical benthic habitats and their communities.
Temporal and spatial scales of influence on near-shore fish recruitment (invited talk, Wednesday afternoon)
Jennifer E. Caselle, Brian P. Kinlan, and Robert R. Warner (University of California, Santa Barbara, California)
Physical processes in the ocean have long been associated with recruitment, but it the exact role that these processes play remains obscure. The development of fine-scale indices of physical processes, coupled with detailed circulation models, has allowed analyses of long-term datasets to illuminate these relationships. Here, we compare subtidal community and recruitment data to spatial and temporal patterns of oceanographic processes operating at different scales. In this way, we can ask, for example, if recruitment is more associated with processes occurring close in time and space to the actual recruitment events (suggesting local transport), or with processes occurring at particular spatial and temporal lags that suggest influences on production. We illustrate this approach using a ten-year record of kelp bass and rockfish settlement to areas in the northern Channel Islands off the coast of southern California. Recruitment in time, space, and species is predictable given a combination of large-scale factors (affecting production in source areas and long-distance transport) and small-scale factors that aid in delivery of competent larvae to suitable nearshore habitat.
The fishery for small pelagic resources in Chile: small-scale and industrial fleets under open-access and share-holder large spatial oceanic allocations (invited talk, Tuesday morning)
Juan Carlos Castilla (Pontificia Universidad Católica de Chile, Santiago)
There is abundant literature on the assignation of exclusive fishing rights to subsistence and/or inshore local small-scale fisher communities, cooperatives and indigenous fisherfolks, who target benthic resources (i.e., algae, invertebrates) and/or species showing restrictive displacing (i.e., coral reef fishes). Nevertheless, in the world there are only few examples where the assignation of fishery exclusive rights refers to truly pelagic species, aiming to achieve a spatial separation of industrial (large-scale) versus artisan (small-scale) fisher share-holders, to avoid competition. In 1991 the new Chilean Fishery and Aquaculture Law (FAL) assigned exclusive fishing rights (all fisheries) within 5 miles, along the coast of continental Chile: 18º 21´- 41º 28´ S, to the small-scale fishery sector, displacing industrial fleets to more open oceanic waters. In Chile, artisan fishery embraces subsistence and commercial activities, including coastal food-gathering and small-scale fleets of out-board engine boats and mid-size (in-board engine) vessels of up to 15 m in length and 80 metric tons of holding capacity. For the exclusive 5 mile and oceanic offshore zones, the FAL decreed four major fishery management areas and corresponding consultative managing bodies. Compulsory artisan and industrial national Fishery Registers were also established. The paper analyses the overall evolution (1970-2006) of Chilean fishery landings, for the small-scale and industrial fleets. Interestingly, since the establishment of the artisan exclusive fishery rights in the 1991, this sector has shown a persistent increase in landings, from 0.54 million metric tons (mmt) in 1992 to 1.9 mmt in 2006. On the contrary, the industrial sector has shown a persistent decline in landings, from a peak of 6.9 mmt in 1994 to 2.3 mmt in 2006. Further, the analysis focuses exclusively on five small-pelagic species: Anchovy, south American pilchard, jack mackerel, Chilean herring and mackerel, for two of the most productive fishing areas of Chile: Regions I&II, Northern Chile; Region VIII, Central- Southern Chile. The first three species were declared fully exploited in 1993 and the Chilean herring in 2000, and since then the authority has decreed yearly extractive quotas: by species, fleets and areas. For these areas, artisan and industrial landings (1992-2006) and vessel holding capacities (1998-2006) are analyzed and discussed. It is concluded that in spite of the challenger to implement this novel policy, under scenarios of environmental changes and variability in Chile (i.e., ENSO), the 1991 FAL´s allocation of exclusive fishery rights to “artisan fisher communities” has indeed: a) Promoted socio-economic incentives to control fishing overcapacity (although no perfect), b) Facilitated the incorporation of Vessel Monitoring System in both fleets, c) Enhanced social organization among artisan fishers, d) Above all, served as a way to reach a more equitable access to fishery resources by different stakeholders. Finally, the paper suggests that fishery share-holder allocations over large spatial oceanic zones may also serve (together with other tools) to determine the carrying capacity of Chilean fisheries, that apparently can not sustain extractions over 3-4 mmt per year.
Fishers supporting fisheries regulation: a major step to start reversing resource degradation—the case of Bahía Kino, Gulf of California, México (YI poster, Thursday afternoon)
A. Cinti,1 C. Moreno,2 R. Cudney-Bueno,1 and W. Shaw1 (1University of Arizona, Tucson; 2Comunidad y Biodiversidad A.C., Guaymas, Sonora, México)
Effective management of fisheries relies on the development of rules that are appropriate for the biophysical and social characteristics of the fisheries, and also on the understanding and internalization of these rules by resource users. Often, however, framing of state-carved policies may lack input from local users, and by the time these policies reach their implementation on the ground, they may be misconstrued, adapted, or completely dismissed by local fishers. Cross-scale interactions and coordination (between governmental and local domains) are critical to make sure that formal rules are not poorly suited to local circumstances so that negative externalities are produced. Small-scale fisheries in the northern gulf of California (NGC) experienced a significant increase in fishing pressure over the last decades. As a means to begin addressing how well governmental rules are suited to local circumstances within fishing communities of the NGC, we conducted research in Bahía de Kino, Sonora. We studied the interpretation and level of support and weight of government regulations through investigating fishers’ understanding of existing government rules, their attitudes and perception concerning formal fisheries regulation, and the factors affecting fishing decisions. We conclude that existing legislation is poorly known and used by local fishers, poorly implemented by local authorities, and insufficient for providing the right incentives for fishers and authorities to care about and cope with resource degradation. Nonetheless, a strong willingness of local fishers to improve fishery’s conditions through regulatory measures exists. We urge that the existing regulatory tools for fisheries administration and their implementation be critically re-examined.
Do global assessments mandate global management of fishery resources? (contributed talk, Tuesday afternoon)
James H. Cowan, Jr.,1 Ray Hilborn,2 Timothy E. Essington,2 Carl J. Walters,3 Kevin Boswell,1 and Kim de Mutsert (1 1Louisiana State University, 2University of Washington, 3University of British Columbia)
In the U.S., modern fisheries management and governance began in 1976 with approval of the Magnuson-Stevens Sustainable Fisheries Act (SFA). Initially, the appropriate scale of management was assumed to be regional, perhaps even local. Since 1976, however, improved information about stock boundaries, trophic dynamics, and the magnitude and nature of fisheries landings has required assessment science to adopt approaches that are inclusive of multispecies interactions, and cognizant of the impacts of fishing on habitats and food webs. Importantly, the pace of change, and scale of management, has been driven by science through improvements in assessment techniques, and data collection and management. More recently, papers published in high profile journals have indicted fisheries science and management for failure to conserve fishery resources, and have justified these indictments via appraisals of resources on ecosystem, or even global spatial scales. Although many of these large-scale appraisals are flawed and have been challenged in the literature, they appear to have had an inordinate effect on the pace of transition towards ecosystem-based fisheries management (ESBFM), relegating fisheries science to a defensive posture. Because the science of ESBFM is complex and cannot keep pace with these appraisals, we fear that they will further encourage Congressional involvement in US fisheries management, and fuel proliferation of “faith-based” solutions (Hilborn 2006). We therefore contend that the spatial and temporal scale of fisheries assessment and management, including the transition towards "ecosystem and/or global" scale approaches, should occur only as an emergent property of innovation in our discipline.
Modeling the effects of management scale for spatially heterogeneous fish populations (YI poster, Wednesday morning)
Dawn Dougherty, Ray Hilborn and André E. Punt (University of Washington, Seattle)
Heterogeneous fish populations can differ spatially with intrinsic rates of growth, carrying capacity and localized fishing pressure. Few stock assessments or catch rules are implemented at this finer biological scale of a species. In this study, we use simulation modeling to determine if management objectives are maximized when managing at the biological scale of a species. As performance measures, we consider the total average catch of the fishery over twenty years, the CV for the total average catch, and the probabilities of fishing below 10 percent and 40 percent of the initial population size for each stock. Multiple biological scales are considered to evaluate the relationship between the biological and management scale when comparing the management objectives. Initial results show that optimal results can be achieved at finer management scales without the need for new data collection efforts. In some cases, optimal results may be achieved at management scales slightly larger than the biological scale of the species.
Spatial Issues in designing marine protected areas for gag grouper in the Gulf of Mexico (poster, Thursday morning)
Robert Ellis and Joseph Powers (Louisiana State University, Baton Rouge, Louisiana)
Spatial scale is of particular importance for designing Marine Protected Areas used in fisheries management. While information about the spatial distribution and movement patterns of populations are critical for evaluating design, often there is a lack of this data. Simulation modeling is one way to create and compare different MPA designs across a range of presumed distribution and movement patterns, while identifying gaps in available scientific knowledge that will help improve management. This poster will present the results of a stage-structured model of the gag grouper (Mycteroperca microlepis) of the northern Gulf of Mexico and its particular life history. The model was created to investigate the efficacy of MPAs for the current management regime, and to investigate changes in the population dynamics of the fishery. Model evaluations guide the discussion of MPA design in the Gulf of Mexico by better defining the necessary information needs.
"Individual discrete fishing spots" as an effective traditional management system: the case study of the Juan Fernández lobster fishery (Chile) (invited talk, Tuesday afternoon)
Billy Ernst (Departmento de Oceanografía, Universidad de Concepción, Chile)
Customary sea tenure in artisanal fishing communities from Latin America started to receive due attention over the last decade. These fisheries are often “unregulated” or have nominal vertical (“command and control”) management systems in which advice is commonly molded after conventional prescriptions, originally conceived for industrial fisheries. Effective traditional management practices often constitute the institutional backbone of small scale artisanal fisheries around the world. These practices are, as a rule, poorly documented, going unnoticed by scientists and managers. We present here the case study of the Juan Fernández rock lobster fishery (off central Chile), a text book example of a traditional sea tenure system consisting of "individual discrete fishing spots" (IDFS). The latter correspond to discrete geographical locations where traps are deployed by single fishermen. We combined three years of onboard field work, interviews and a monitoring program to study this customary marine tenure system and to interpret its role in sustainable management. We present results of cost-effective scientific monitoring and research programs conducted jointly with the fishermen, and crafted to complement existing practices. A search of the literature indicates that IDFSs are found in other small scale fisheries around the world, differing substantially from conventional TURFs.
Putting life into ecosystem-based management theory: a spatially explicit planning application using information on marine biodiversity and fisheries (contributed talk, Wednesday morning)
Zach Ferdaña1 and Michael W. Beck2 (1The Nature Conservance, Seattle, Washington; 2The Nature Conservancy, Santa Cruz, California)
Ecosystem-Based Management (E-BM) considers the cumulative impacts of different sectors and is intended to reverse the order of management priorities to start with the ecosystem rather than the species. Although genuine in its approach, transitioning this concept into a GIS and spatial analyses to ultimately support decision-making is complicated and the path to its realization is unclear. However, marine spatial planning offers great opportunity to place information representing multiple management objectives into a flexible and repeatable framework.
This talk provides an overview of how to utilize spatially-explicit fisheries data on marine fish and fishing effort, a fisheries-based ecosystem model and a priority conservation site selection tool within a single spatial planning framework. Conservation planning and fisheries modeling can be incorporated into an integrated approach illustrated here by analyzing information on ecosystems, habitats, species and human influences in the Oregon and Washington portion of the Northern California Current. This GIS-based analysis demonstrates the use of two commonly used decision support tools for biodiversity conservation and fisheries objectives, Marxan and Ecopath with Ecosim, respectively. This is one example where both tools are used to provide initial planning solutions that fulfill multiple objectives.
One practical and powerful way to realize E-BM is to make information and analyses transparent to decision makers and advance integrated tool development.
Cooperative research and comanagement arrangements in support of area-based fishery management (invited talk, Tuesday morning)
R. M. Fujita,1, K. T. Honey,2 A. Morris,3 H. Russell,1 and J. Wilson4 (1Environmental Defense, San Francisco, California; 2Stanford University, Pacific Grove, California; 3National Marine Fisheries Service, Santa Cruz, California; 4University of California, Santa Barbara)
Fisheries management at its core is concerned with the management of human behavior. Management institutions operating at different spatial scales create different kinds of hierarchies, relationships, and incentives. The scale at which management decisions are made can be an important determinant of the effectiveness of these decisions. Stock assessments and the resulting harvest rules that take place at large geographic scales can introduce monitoring inaccuracies, create harvest inefficiencies and perverse incentives, impose unfavorable social impacts, and result in poor conservation and economic performance. Management institutions that fail to address the dynamic interaction between resource user and resource can lead to distrust, disputes over “best available science”, and unwillingness to pay for management that is perceived as threatening. In this paper, we examine the efficacy of fishery management conducted at smaller geographic scales in the context of opportunities for co-management in which different degrees of responsibility (with attendant levels of accountability) are decentralized. Small-scale, adaptive, comanagement approaches are practiced throughout the world, with often impressive success, but have yet to be integrated into mainstream U.S. fisheries management. Here, we apply the theory and practice of cooperative and collaborative research and management (including failures and lessons learned) to develop assessment tools and a strategic framework for introducing and implementing co-management as a means for improving the sustainability of small-scale fisheries in the U.S.
Fishing the line? Commercial lobster fishermen’s effort response to marine reserves at the Channel Islands State Marine Reserves in California (YI contributed talk, Thursday afternoon)
Carla Guenther, David Carr, and Hunter Lenihan (University of California, Santa Barbara)
In April 2003, California established a network of no-take marine reserves around the northern Channel Islands. Prior to the reserves enclosing nearly 20% of the islands’ nearshore area, twenty-five commercial lobster trappers harvested 50% of the regional annual catch from the Channel Islands. To best manage marine reserves and affected fisheries we must ask a critical question: Where do the fishermen go? Spillover theory emerging from models of marine reserves and adjacent fisheries suggests displaced fishermen will concentrate their effort along reserve borders; a phenomenon called “fishing the line.” These models do not consider habitat heterogeneity nor fixed-gear fisheries such as lobster where traps are set, soaked for 1 to 3 nights, pulled and re-set. With fixed-gear fishing space is “marked” or occupied, and reduces the possibility of another fisherman to fish a hot spot. Lobster trap fisheries are notoriously territorial as a result. Lobster fisheries therefore stand to experience a skewed impact based on a priori territorial distributions and habitat quality. At the Channel Islands, seven fishermen left fishing at the islands and remaining fishermen have not increased their fishing effort (e.g., number of traps, fishing days) thus resulting in a net 39% decrease in the number of traps set around the islands. What is the distribution of these traps? We use a Geographic Information Systems (GIS) analysis of 8 years (5 before reserves and 3 after) of fishery-dependent data complemented with fishery interviews tests theories of commercial fishing adaptation to spatial closures.
Adaptive sampling proves assessment of marine reserves for fisheries (poster, Wednesday morning)
K. T. Honey (Stanford University, Pacific Grove, California)
Adaptive sampling is an experimental technique that uses accrued data (i.e., observations) to make adjustments to a research design, while research is in progress. Using SCUBA surveys, I examined how ocean-swell conditions at the local scale (10-1000s m scale) affect juvenile- and adult-fish-assemblage structure in nearshore rocky reefs of marine reserves in Monterey Bay, California. I found significant correlations for how swell conditions affect observed abundances and assemblages of juvenile and adult fish in rocky reef habitat. Ocean swell is a relatively easy-to-measure process that serves as a proxy to characterize survey bias in dive counts of nearshore fish populations. Adaptive sampling methods, which respond to local conditions in near-real time, yield more informative data at lower costs. With appropriate application, adaptive designs will improve the accuracy and cost-effectiveness of data collection in marine reserve assessments and legally mandated monitoring goals. In California, this means satisfying monitoring requirements under the Marine Life Protection Act at the lowest possible cost to tax payers. Currently, however, marine ecologists and fishery scientists typically conduct "fixed" sampling procedures, where all decisions regarding design are made prior to data observation. For dynamic environments like nearshore marine ecosystems, these "fixed" procedures may be suboptimal?they lack flexibility and learning occurs only at the conclusion of the experiment. Adaptive procedures overcome such limitations. They work with natural dynamic processes, which are often inherently sequential and characteristic of marine systems, in order to efficiently allocate limited resources without diminishing the statistical power of the procedure.
Spatial assessment of a fish stock: a sorting method approach with commercial fishery data (contributed talk, Thursday afternoon)
Ling Huang and Martin D. Smith (Duke University, Durham, North Carolina)
Underlying fishermen’s fishing location choices are interconnected biological and economic subsystems. To earn profits, fishermen respond to pure economic factors such as price and fishing costs as well as the spatial distribution of fish abundance. We analyze fishing location choices with a sorting model in order to isolate pure economic drivers of fishing behavior from the otherwise unobserved spatial distribution of fish stocks. We employ a two-step estimator of the fish stock in each location. First, we use a discrete choice model to obtain the spatial fixed effects of different locations after controlling for economic influences on behavior. Second, we use a regression/nonparametric method to separate the hidden stock information from other location-specific characteristics such as waterbody area and congestion externalities.
We estimate the model on the North Carolina shrimp fishery with a rich dataset from the North Carolina Division of Marine Fishery trip ticket program. In the fist step, we use contraction mapping to address the computational burden from the nonlinearity of the model, the large data set, and the high dimension of the choice set and parameter space. In the second stage, since the spatial distribution of fishermen is endogenous, we use environmental variables—including salinity and low dissolved oxygen—as instruments to control for agglomeration or congestion externalities. The paper presents a stock distribution map in the Albemarle/Pamlico estuary in North Carolina. Our model provides insights on how to assess stocks spatially with commercial fishery data and could assist policy makers in designing spatial policies.
Integrating biodiversity indices into spatial management of the marine environment: examples from the Northwestern Atlantic shelf (contributed talk, Thursday morning)
Adrian Jordaan (Stony Brook University, Stony Brook, New York)
De facto Ocean zoning presently occurs due to a heterogeneous distribution of human activities. To effectively use zoning, basic management units should reflect ecological gradients and draw on important metrics of ecosystem health, such as biodiversity. Three fisheries surveys will be used to demonstrate how species abundance data can be analyzed to provide biodiversity indices to guide marine spatial planning. First, Principal Component Analysis (PCA)-bootstrap methodology is used to identify species’ assemblages across survey regions using eigenvectors. Second, the PCA scores are tested against environmental variables. Third, the spatial structure is evaluated using GIS-generated maps. I will draw on three collaborations: (1) Maine Coast Survey: Y Chen, DW Townsend; University of Maine, S Sherman; Maine DMR. (2) Gulf of Maine (NMFS) Survey: M.G. Frisk, Stony Brook University; N.H. Wolff, L.S. Incze and L. Hamlin, University of Southern Maine; Y Chen, University of Maine. (3) NY Ocean Survey, K Dunton, MG Frisk, DO Conover; Stony Brook University.
Trawl data is analyzed to create management zones using persistence in biodiversity gradients to delineate regions. Trends in biodiversity will be corroborated across common regions and patterns discussed. For example, the NY Survey identified Atlantic sturgeon (Acipenser oxyrhincus) aggregations embedded within an overall gradient in biodiversity. I will discuss how both the lack of area-based management as well as any potential reserve for species protection can negatively effect components of biodiversity. This involves some potential problems due to the scale of observation of surveys, aggregations of species and seasonal patterns in habitat use.
Strategic roles of a multiple-use protected area in managing a marine ecosystem (invited talk, Tuesday afternoon)
Richard Kenchington (University of Wollongong, Wollongong, New South Wales, Australia)
Biodiversity and ecosystem management responses to an increasing range of human uses and impacts on marine ecosystems are a recent phenomenon. They are developing alongside longer standing traditions of sectoral management of fisheries, shipping and coastal land management. Modifications of terrestrial concepts of land use planning, environmental risk management and area protection have been introduced in marine contexts to address new and multiple uses and impacts. A very large number of acronyms identifies differing management regimes for approaching the tasks of integrating management of coastal and marine ecosystems. The role of Protected Areas and conservation agencies in such regimes is often a matter of contention.
The application of IUCN Protected Area categories to marine ecosystems can cover the broadest range of management regimes from strict nature reserves with no fishing or collecting to multiple, verifiably environmentally sustainable, levels of use and impact. This paper reflects on the roles of protected area categories in relation to strategic marine ecosystem management objectives. It draws on experiences of management and community response to the Great Barrier Reef Marine Park in order to discuss the opportunities and challenges of protected area categories in management for conservation and reasonable multiple use at the ecosystem scale.
The role of spatial dynamics in the stability, resilience, and productivity of an estuarine fish population (YI contributed talk, Wednesday afternoon)
L. A. Kerr,1 S. X. Cadrin,2 and D. H. Secor1 (1University of Maryland Center for Environmental Science, Solomons, Maryland; 2NOAA/UMass Cooperative Marine Education and Research Program, Fairhaven, Massachusetts)
Understanding mechanisms supporting long-term persistence of populations and sustainability of productive fisheries is a priority in fisheries management. Complex spatial dynamics is increasingly viewed as a plastic behavioral response that can contribute to population stability and resilience. Here, spatial dynamics and environmental forcing were incorporated in interacting local population models to examine the consequences to population stability (coefficient of variation of spawning stock biomass), resilience (time to recover from disturbance), and productivity (spawning stock biomass). White perch (Morone americana) served as a model species that exhibits generalized resident and dispersive spatial life histories. The role that contingents, portions of a population exhibiting divergent spatial life histories, play in mitigating population responses to unfavorable environmental conditions was evaluated. Age-structured models incorporating contingent-specific vital rates were used to simulate population dynamics of white perch in a sub-estuary of Chesapeake Bay. The effect of contingent structure on the dynamics of the population was sensitive to the proportion of individuals within each contingent. Increased levels of dispersal within the population resulted in increased productivity and resilience, but decreased stability. Contingent structure is important in maintaining population persistence, highlighting the need to conserve spatial structuring within populations and to plan for spatial management of populations that includes habitat-specific regulations. The degree to which the results of the white perch model can be generalized will be explored through tailoring the model structure and parameters to other fish populations (Atlantic herring Clupea harengus and Atlantic cod Gadus morhua) that exhibit spatial structure.
Modeling and predicting the spatial distribution of pelagic fishery resources (YI contributed talk, Wednesday morning)
Kristin M. Kleisner1 and John F. Walter III2 (1University of Miami, Florida; 2NOAA Southeast Fishery Science Center, Miami, Florida)
Though highly dynamic, the pelagic environment possesses spatial structure that is critical to the existence of its inhabitants. Simple modeling suggests that predators randomly distributed in a random prey field would starve if not for structuring that aggregates both predator and prey. We use model-based geostatistical techniques to model and predict spatial abundances of dolphinfish (Coryphaena hippurus) and swordfish (Xiphias gladius) in the Gulf of Mexico using longline catch per unit effort (CPUE) from 1987 to 2005. We partitioned catch rates into two components, the probability of encounter, and the abundance, given a positive encounter. We obtained separate variograms and kriged predictions for each component and combined them to give a single density estimate with corresponding variance. By using this two stage approach we were able to detect patterns of spatial autocorrelation that had distinct differences between the two species, likely due to differences in vertical habitat utilization. The patchy distribution of many living resources necessitates a two-stage variogram modeling and prediction process where the probability of encounter and the positive observations are modeled and predicted separately. Such a ‘geostatistical delta-lognormal’ approach to modeling spatial autocorrelation has distinct advantages in allowing the probability of encounter and the abundance, given an encounter to possess separate patterns of autocorrelation and in modeling of severely non-normally distributed data that is plagued by zeros.
Economic valuation of global fisheries under climate change (YI contributed talk, Thursday afternoon)
Vicky W. Y. Lam, William W. L. Cheung, and Rashid Sumaila (University of British Columbia, Vancouver, Canada)
The objective of this paper is to determine the effect of climate change on the landed values that can be derived from the world’s marine resources, mainly, fish and invertebrates. Climate change can lead to shifts in the distributional range of marine fishes and invertebrates. Since the distribution of commercial marine species affects the quantity and pattern of catch, change in climate is predicted to affect global fisheries productivity. We estimate global landed values of commercially exploited marine species under climate change for year 2050 using the global price ex-vessel price database reported in Sumaila et al. (2007). We then compare this value with what is currently obtained (assumed to be the "without" climate change scenario). The computed landed values will be spatially defined in half degree by half degree cells. This allows us to compare the landed values within nations’ Economic Exclusive Zones (EEZs), in particular, those of the top 15 fishing nations of the world, under climate change versus without climate change. This study is crucial as it is the first step towards assessing the socio-economic impact of global climate change through fisheries.
Community-based collaborative fishery research: assessing fishery and socio-economic impacts of marine reserves at the Santa Barbara (California) channel islands (poster, Tuesday afternoon)
Hunter Lenihan,1 Matt Kay,1 Chris Miller,2 and Jono Wilson1 (1University of California, Santa Barbara; 2California Lobster and Trap Fishermen's Association, Los Alamos, California)
Marine reserves provide a promising tool for conserving ecosystem services, especially biodiversity, habitat structure, and areas of scientific and recreational interest. Whether and how reserves can be integrated in the development of ecosystem-based fishery management is of great interest to fishermen, scientists, resource managers, and hopefully the public. Standard ecological theory predicts that reserves can influence nearby fisheries through the build up of biomass within reserves and subsequent export of propagules and/or spillover of adults. Newer ideas linking reserves to fishery management focus on the comparisons of demographics, population dynamics, and spatially-explicit patterns of productivity in target species inside vs. outside of reserves, as well as subsequent use of that information in both traditional and more rapid-response stock assessment models. We will present ideas and results from a collaborative research effort among university scientists, Southern CA Lobster and Trap Fishermen, and fishery managers (see http://www.calobster.org) designed to explore the effects of Channel Island marine reserves on CA spiny lobster populations, fishery yield, and development of community-based stock assessment. Our project is linked to a companion project designed to assess the socio-economic impact of the Channel Islands reserves on the local lobster fishery.
Collaborative fishery research in the Santa Barbara Channel: the CALobster program and spatially explicit management based on marine reserve monitoring (contributed talk, Thursday morning)
Hunter Lenihan,1 Matt Kay,1 Jono Wilson,1 Chris Miller,2 and Kristine Barsky3 (1University of California, Santa Barbara, California; 2California Lobster and Trap Fishermen's Association, Los Alamos, California; 3California Department of Fish and Game, Ventura)
The commercial fishery for California spiny lobster (Panulirus interruptus) began in the mid-1800s and has enjoyed relatively consistent catches, at least over the past several decades. The sustainability of lobsters is generally attributed to long-standing regulations including seasonal closures, size limits, and trap designs. More recently, the commercial lobster fishery has faced a number of new management obligations and opportunities including: limited entry, permit transferability, marine protected areas (MPAs), development of a fishery management plan (FMP), and a potential sustainability certification. The live-trapping of rockfish is a relatively new fishery greatly constrained by precautionary management based on the paucity of data on stock sizes and structure. We have built a collaborative research partnership (CALobster; http://www.calobster.org) that joins lobstermen, trap fishermen, marine scientists, and resource managers in a collective effort to generate modern (i.e., data-rich, spatially-explicit, incentive-driven, and adaptive) management strategies that will assist state managers operating under stringent financial and time constraints. Short-term objectives CALobster include monitoring Channel Islands MPAs and enhancing fishery research through collaboration. Long-term objectives include developing community-based co-management, a barefoot ecology program, ensuring sustainability, and protecting working harbors. Research around MPAs reveals that traps for lobster and rockfishes placed inside reserves catch significantly more and larger animals than traps outside reserves. Ongoing tag-recapture studies are yielding important information about spatially-explicit growth and movement patterns of sublegal and adult animals. These data are being incorporated into models that describe population dynamics inside and outside of reserves, information that is being used in a new generation of stock-assessment models that utilize MPAs as proxies for ecosystem baselines.
Evidence of severe erosion in stock structure and risk of misleading catch rate trends caused by behavior of fishers for gag grouper (contributed talk, Thursday afternoon)
W. Lindberg,1 D. Marcinek,1 Z. Biesinger,1 M. Christman,1 R. Watkins,1 D. Murie,1 D. Mason,2 T. Frazer,1 and C. Walters3 (1University of Florida, Gainesville; 2MPA Great Lakes Environmental Research Laboratory, Ann Arbor, Michigan; 3University of British Columbia, Vancouver)
The vulnerability of Mycteroperca fisheries (e.g. gag) to hyperstability in CPUE may be greatly unappreciated. We surveyed ~13,000 hectares of shallow seafloor (<25m) in the northeastern Gulf of Mexico with 600 kHz side-scan sonar, and censused gag (M. microlepis) across hard-bottom habitat features that varied in intrinsic habitat quality. Unexpectedly high occurrences of zero (=50% of sites) and low (<6) gag abundance among high quality sites indicates reef features get “fished out” and maintained that way. Only ~10% of sites had gag counts typical of this gregarious reef fish under no or low fishing pressure. Results were consistent with the smaller, complex features having gag. Two sites with higher counts (58-76 gag) also tended to be isolated; one site dropped from 58 to 13 gag between 2006 and 2007, while the more isolated feature increased from 61 to 76 gag. To explore implications of these initial results, a spatially explicit simulation model was developed using natural mortality, recruitment of new gag and assumptions of fishing effort movement among reefs to predict CPUE trends over multiple years. The model routinely yielded hyperstability in CPUE. With reasonable parameter values for effort movement, the model also surprisingly predicted that CPUE can actually increase while the stock is declining (i.e. “superstable” rather than “hyperstable”), due to fishers targeting their effort more precisely as they learn which reefs are no longer worth fishing. The spatial-temporal behavior of fish and fishers interact in a manner warranting further research and caution with assumptions inherent in stock assessments.
Development and prospective of the Galician TURF system (NW Spain)—the case of the gooseneck barnacle (Pollicipes pollicipes) fishery (YI poster, Tuesday afternoon)
Gonzalo Macho,1,2,3 Juan Freire,4 and José Molares2 (1Centro Tecnológico del Mar, Vigo, Spain; 2Centro de Investigacións Mariñas, Vilanova de Arousa, Spain; 3University of Washington, Seattle; 4Universidad de Coruña, Spain)
Galicia is an autonomous Spanish region with full authority over the management of its coastal fisheries. In 2006 Galician shellfisheries targeted approximately 55 species (18,500 tons, $191 millions), involving nearly 16,000 fishers distributed in 62 fishers’ organizations known as “confrarías”. In 1992 the regional government introduced a new model for Galician small-scale, spatially structured fisheries targeting sedentary resources, so called “S-fisheries” (bivalves, equinoderms, gastropods, annelids and the crustacean gooseneck barnacle P. pollicipes). It promoted a co-management system between fishers’ organizations and the fisheries authority based on territorial use rights (TURFs). Under the new regime there is a requirement for any S-fishery to have an approved annual plan of exploitation and management. Since 2000 detailed information is obligatory, including a list of fishers and boats, a chart of exploited grounds, specification of production and economic objectives, a stock assessment, daily records from previous years (effort, catch, CPUE, sales and fishing area), harvesting, surveillance and trade plans, stock enhancement actions, and a financial plan. The management plan is normally prepared by a “barefoot ecologist” (sensu Prince 2003) working at the confraría with government funding thanks to an arrangement that started in 1996 (up to now 40 out of 62 confrarías are involved in this plan). The “barefoot ecologist” is usually a Biology or Marine Science graduate working as a shellfish resource management assistant, dealing with not only data collection and analysis but also on fishers´ organization improvement. The development, daily implementation and prospective of the Galician model are illustrated in this poster with the gooseneck barnacle fishery as an example. The role of the “barefoot ecologists” on the sustainability of these fisheries is highlighted.
Impacts of co-management of marine protected areas in the Philippines (YI poster, Tuesday afternoon)
Ronald J. Maliao and Ralph G. Turingan (Florida Institute of Technology, Melbourne)
While there is a consensus that marine protected areas (MPAs) help rebuild depleted stocks, several studies reported mixed to negative results. Most MPA impact evaluations also focused on the status of fisheries, putting the perceptions of local communities of fishers on the sideline. We meta-analyzed the impacts of MPAs in the Philippines using social and ecological indicators, with an aim to accumulate knowledge of the effectiveness of MPA as a conservation tool. Under the social component, we used the co-management impact indicators as prescribed by the Worldwide Collaborative Research Project on Fisheries Co-management (WCRPFC). Under the ecological component, we used fish trophic guilds and families as the analytical unit and compared abundance before and after MPA implementation. Our analysis revealed that under the social component, fish abundance, fisher’s income, and access to resource are perceived to continually decrease, and the magnitude of decrease is correlated with the duration of MPA management. In contrary, other co-management indicators related to operational level dynamics, i.e., communication, rule compliance and conflict resolution have significantly improved, indicating that MPAs empower local fishers. The results of the ecological component indicated that while total fish abundance have significantly increased, the bulk of the increase is accounted by the non-food species (Pomacentridae, omnivores) while all other groups have decreased or remained either stable relative to the baseline abundance. We offer three hypotheses to explain our results: first, recovery rate of fish is slow and gradual; second, extraction rate outside the MPA exceed the recovery and/or spillover rate from the MPA; and third, poaching occurs. The combined results of the social and ecological indicators challenge the current consensus of the effectiveness of MPAs. Nonetheless, our analysis indicated that co-managed MPAs set the stage for community empowerment.
Cross scale translation of sub-population level nursery habitat dynamics to metapopulation level recruitment dynamics: a case study combining generalized additive habitat suitability modeling with analyses of spatial synchrony (invited talk, Wednesday afternoon)
John P. Manderson (NOAA James J. Howard Marine Sciences Laboratory, Sandy Hook, New Jersey)
Recent studies indicate that subpopulation connectivity is much lower than expected for many marine species. In these cases, metapopulation approaches could lead to better understanding of the mechanisms regulating regional population dynamics. I combined metapopulation level analyses of new recruit production with sub-population level analyses of habitat effects on early life processes to show how habitat effects may regulate regional recruitment. In this case study of Mid-Atlantic Bight winter flounder, new recruit production was asynchronous among sub-populations during periods of moderate spring climate. However, when warm springs were frequent, recruitment synchronized among sub-populations =250km apart. Generalized additive modeling demonstrated that habitat factors variable at fine spatial scales with slow to fast temporal dynamics (< 2.5km, decades-days; e.g., substrate, depth, prey, predators) as well as coarser scale climate driven factors with "fast" dynamics (=10km, days-weeks; e.g. temperature, freshwater discharge) regulated larval settlement, juvenile growth and mortality within sub-populations. Optimal nurseries formed where specific values for multiple factors "nested" in space and time during the critical period. When climate was moderate, fine scale habitat variation appeared to produce asynchronous recruit production in nearby sub-populations. Under these circumstances, metapopulation age class structure and dynamics were relatively stable. However, during extreme periods, coarse scale climate driven factors synchronized sub-population production producing unstable age distributions and "boom and bust" metapopulation dynamics. For resource species with low dispersal rates, a framework blending metapopulation perspectives with the concept of "nested" dynamic habitat could allow environmental variation to be directly incorporated into spatially and temporally explicit population models.
Examining seasonal movement and habitat use patterns of adult common snook (poster, Wednesday afternoon)
L. L. Marcinkiewicz (NOAA Northeast Fisheries Science Center, Woods Hole, Massachusetts)
Common snook, Centropomus undecimalis, are an ecologically and economically important estuarine dependent predatory fish species found throughout south Florida. Despite increasingly restrictive management actions over the past 50 years, common snook populations are thought to have declined. Possible reasons for this decline are high harvest rates, increasing natural mortality due to red tide blooms, and loss of essential habitat related to coastal development. I evaluated habitat use and movement patterns for adult snook in seasons with and without large-scale environmental (red tide blooms) and anthropogenic (dredging) disturbance events. The results of this study support much of the literature on snook life history while providing new behavioral information regarding movement, site fidelity, and habitat disturbances. This study provides important information for conservation management purposes and improves the understanding of direct and indirect effects of habitat threats associated with anthropogenic and environmental disturbances on snook populations. This understanding of habitat-species relationships is important because of the large emphasis placed on managing habitat in various State and Federal conservation programs for fish and wildlife resources.
Rotating spatial closures can improve conservation and recreational fisheries values for sedentary species at risk of growth overfishing (contributed talk, Thursday morning)
Steven J. D. Martell, Robert Ahrens, and Carl J. Walters (University of British Columbia, Vancouver)
Various sedentary demersal species like Florida groupers and West Coast rockfish are facing growing impact from recreational fisheries, to which fish typically become vulnerable to capture at relatively low sizes and ages. Size limits have been used to reduce the growth overfishing caused by taking fish when they are too young, but this results in high wastage due to discard mortality of undersized fish. Pulse or periodic harvest policies, where fishing is allowed one year out of every four, can greatly reduce the impact of growth overfishing in general; long “fallow periods” allow strong year classes to grow to near optimum sizes for harvesting. When combined with elimination of size limits, periodic policies can give nearly the same biomass yield as the best annual fishing option, while eliminating waste and dramatically increasing the total number of fish caught. When implemented by closing spatial areas in rotation, so that each spatial area is fished only once every several years, periodic harvest policies can also radically reduce the risk of recruitment overfishing by exposing only a small proportion of the total stock to harvesting every year.
Can we use information from marine protected areas to inform management of small-scale, data-poor stocks? (contributed talk, Thursday morning)
R. Carey McGilliard,1 John Field,2 and Alec MacCall2 (1University of Washington, Seattle; 2NOAA Fisheries, Southwest Fisheries Science Center, Santa Cruz, California)
Many small-scale, multi-species fisheries tend to be data-poor, with modest availability of life history information and data on trends in abundance. For example, nearshore fisheries off of California and Hawaii are managed largely as assemblages. In California, the assessments that have been conducted on nearshore species are typically data-poor, relying on catch per unit effort time series due to the absence of fishery-independent surveys. In Hawaii, a diverse assemblage of demersal species is treated as a single stock in assessments. With impending mandates for setting TACs for each species, financially feasible methods are needed to assess stock status and ensure the sustainability of individual populations. In California and many other regions, marine protected areas have been implemented as ocean management tools, and a comparison of demographic and trend information within and outside MPAs could provide insights on stock status. In this study we use Management Strategy Evaluation to test a management strategy that adjusts catch limits based on the differences in population trends within MPAs relative to open areas, based on CPUE data from cooperative surveys. We simulate spatial, two-species operating models, testing a suite of assumptions about species interactions, movement, and fleet dynamics. Length frequency data, as related to the spawning potential of an unfished stock, is also evaluated as a management tool. These MSE simulations identify control rules that are most likely to ensure population viability for all species.
The back-ended issues of US fisheries management (YI contributed talk, Tuesday afternoon)
Chad J. McGuire,1 and Bradley P. Harris2 (1University of Massachusetts, Boston; 2University of Massachusetts, Dartmouth)
In response to over-exploitation and ecosystem degradation, U.S. fisheries policy is shifting from species-based to ecosystem-based management. In addition, the reauthorized Magnuson Act prescribes a year 2011 deadline to end over-fishing, market-based incentives, strengthened enforcement, and improved cooperative conservation efforts. We refer to these proposed solutions (including the “status quo”) as front-ended policy considerations. Left unresolved are what we term back-ended issues, which surround the jurisprudential limitations that inhibit full consideration of ecosystem-based management principles and scientific information. We examine the jurisprudential limitations (including the standard or review) in detail, and propose solutions to these major governance obstacles. The goal is to identify recurring “framework” issues in U.S. management if, left unresolved, will continually limit the application of front-ended solutions including rights-based governance structures.
Patch structure of marine benthic species on tTerritorial use rights for fishers: an approach to the bed concept (contributed talk, Wednesday morning)
Carlos Molinet,1,2,3 Heriberto Figueroa,4 Maria Teresa González,5 Edwin Niklitschek,2,3 Alejandra Arévalo,1 José Codjambassis,1 Viviana Almanza,6 and Manira Matamala6 (1Universidad Austral de Chile, Puerto Montt, Chile; 2Universidad Austral de Chile, Coyhaique, Chile; 3Centro de Investigaciones en Ecosistemas Patagónicos, Coyhaique, Chile; 4Universidad Austral de Chile, Campus Isla Teja, Valdivia; 5Universidad de Antofagasta, Antofagasta, Chile; 6Consultora Pupelde, Puerto Montt)
The study of beds of marine benthic species can be undertaken using an ecological approach that is associated with the dispersal patterns of the organisms and a fishery approach associated with commercial exploitation of the species; these approaches are rarely dealt with in the scientific literature. Herein, we study the presence of spatial structures of benthic species in Territorial Use Rights for Fishers (TURFs) in Chile in order to evaluate the implicit, qualitative judgement of divers requesting an area for the exploitation of benthic species versus the spatial structure of the species in these areas. This was done by analyzing information from studies of Chilean TURFs, using aggregation indices, connection networks, and autocorrelation techniques to evaluate the presence of the spatial structures. The results show that the scale of TURFs allows observing patches of the target species, although it is not clear if the scales applied to the management are appropriate for the species considered in this study.
Science, Local Knowledge, and geographic information systems (GIS) in small-scale fisheries management: case study: PANGAS Project, Northern Gulf of California, Mexico (YI contributed talk, Tuesday afternoon)
Marcia Moreno-Baez, Barron Orr, William Shaw, and Richard Cudney-Bueno (Universeity of Arizona, Tucson)
The Northern Gulf of California contributes most of Mexico's fishery resources and fish products for both national and international markets. The performance of small-scale fisheries is governed by complex interactions and feedbacks between human and biophysical systems. Sustainable management of small-scale fisheries relies on identifying and understanding these processes; consequently decision-making and overall management is constrained by the level of available information.
Small-scale fisheries involves a wide array of fishing gear, methods, species, and also takes place in a variety of habitats and under various socio-political settings. Knowledge of local people is crucial to fill in missing information required for the evaluation, design, and analysis of various aspects in this multidisciplinary topic. Following a systematic integration of baseline scientific information using GIS, local knowledge is collected and integrated. This process is followed by a data validation process in order to minimize inconsistency due data transformations and to maximize the impact of local knowledge in research, planning and management.
This paper considers the implications of this approach for the design of fisheries management plans, where scientific knowledge derived from traditional fisheries data collection and analysis is combined with local knowledge using GIS. In summary, we implement this approach with a final goal of incorporating and validating local knowledge in the design of a small-scale fisheries management plan for the northern Gulf of California, Mexico.
Quantifying spatial dynamics in fishing activity: application of electronic data collection and GIS to an age old problem (contributed talk, Thursday afternoon)
Craig Mundy1 and Andrew Sharman2 (1University of Tasmania,
Hobart, Tasmania, Australia; 2Department of Primary Industry and Water, Hobart, Tasmania, Australia)
Small-vessel fisheries (<7 m) typically target spatially structured stocks, often in remote areas. The nature of these fishing operations means precise recording of fishery-dependent data is challenging, and fishery independent data collection is cost prohibitive. While annual catches are negligible compared to industrial fisheries, small fisheries are economically significant to regional communities. These low value fisheries are commonly constrained by meagre government resources and limited ‘attractiveness’ to researchers because funds are rarely forthcoming. Typically, we see that assessments of these fisheries (if done) are based on large reporting units, with low-level precision data. Information on spatial structure and stock productivity, and dynamics of the fleet are lost.
The Tasmanian Abalone Fishery happily falls into the category defined above as a spatially structured, small vessel fishery with limited resources. Dynamic international exchange rates, increasing aquaculture production, and rising fuel prices have created a changed economic climate, with a corresponding modification in harvest strategies employed by divers, or imposed by quota owners.
Without fishery independent abundance data to rely on, capturing the changes in fisher behaviour and fleet dynamic are central to attribution of changes in CPUE signals to stock decline or, changed harvest strategy, or both. An electronic data collection system has been developed at TAFI, using a combination of GPS and depth/time dataloggers to collect high-resolution, high-quality spatial location and effort data from abalone divers. Examples of the benefit of this approach are given using spatial performance measures, and the ability to quantify fleet dynamics and fisher behaviour.
Marine spatial fisheries management, a paradigm shift (invited talk, Thursday morning).
Elliott A. Norse (Marine Conservation Biology Institute, Bellevue, Washington)
Fishery management reflects the world-view of fishery managers, which is shaped by the world-views of natural and social scientists, politicians and the popular culture. If the ocean were a homogeneous fluid in which physical and biological processes evenly distributed organisms over economically meaningful time scales, managing fisheries would be less failure-prone, even if they were not desirable in other ways. (Fisheries cannot be sustainable unless they are managed in ways that fully integrate both our understanding and lack of understanding of marine ecosystem distribution and functioning, and the diverse desires of society.)
Until recent decades, poor understanding of 1) seafloor topography and 2) the spatial structure of the water column; 3) computational weaknesses that led to oversimplified population models; and 4) conceptual weaknesses that led fisheries biology to become a kind of applied population biology, not applied ecosystem ecology) led fishery management to treat fish populations as spatially homogeneous within their ranges. Doing so errs for the following reasons: 1) the great majority of fishes and other marine organisms are associated with the seafloor, which is spatially heterogeneous: a) geologically, b) in currents which deliver propagules and food; c) biologically, in that organisms and processes that shape them are unequally distributed in space and time; d) economically, in that some fishes can be pursued and caught more profitably in some places than in others, and e) legally, in that governments long ago imposed spatial boundaries on marine ecosystems that most often did not reflect ecologically and socioeconomically meaningful ecosystem and population boundaries then or now.
Managing for this heterogeneity requires a new fishery world-view, a place-based one that recognizes the new natural and social science understanding we have gained in recent decades; in other words, a paradigm shift. Knowing little more than the lessons from Clark (1974), Pauly et al. (1998), Watling and Norse (1998), Jackson et al. (2001), Roberts et al. (2001), Day (2002), Halpern (2003), Berkeley et al. (2004), Norse (2005), Crowder et al. (2006) and Ehler and Douvere (2008) leads to the unavoidable conclusion that successfully managing of marine fisheries and the marine ecosystems in which fisheries are embedded must be spatial.
Spatial management would be a fisheries and ocean management paradigm shift. In addition to reflecting our increasing scientific understanding of reality, a spatial management system would have the following advantages for fisheries: 1) It could be sustainable, even in an unpredictably changing world; 2) it could optimize economic returns for fishing interests while amply conserving the broader society’s interests in healthy marine ecosystems, thereby offering groups with different interests ways to increase the probability that each will get what they want (it could be a positive-sum game with win-win solutions); 3) it will be much, much easier to enforce, freeing up resources needed for other management needs; and 4) it will therefore be far more viable ecologically, economically and politically. Society can also choose to make it fair. The fact that healthy fisheries and healthy ecosystems are not mutually exclusive creates the possibility of new outcomes that do not happen under the current zero-sum management paradigm, in which it often seems that if the environment wins, fisheries lose, and vice versa. But it would be difficult to imagine a more exciting challenge than optimizing fisheries profitability while recovering marine biodiversity.
The only real disadvantage of changing the paradigm is that some individuals and institutions are stuck in a past that, however unsatisfying, is at least familiar and certainly less daunting than the prospect of fashioning a new place-based fishery management system that can actually work for oceans and for people who depend on them. The question, then, is: “Are the many rewards of having vibrant fisheries and marine ecosystems worth the nontrivial costs and difficulties which we will inevitably encounter in changing the way we manage fisheries? In other words, do we have what it takes to change as the world—and our understanding of it—changes? And if we do not, then shouldn’t we step aside and make way for those who do?
Linking spatial dynamics of the early life history of snow crab in the eastern Bering Sea to fisheries (invited talk, Wednesday afternoon)
Carolina Parada (NOAA Alaska Fisheries Science Center, Seattle, Washington)
Snow crab (Chionoecetes opilio) has supported one of the most lucrative fisheries in the eastern Bering Sea, but landings have declined to historically low levels. The geographic range of the reproductive females has retracted to the northwest. There is concern about whether the southeast shelf can be repopulated via larval advection to the south, as hatching is now downstream. We present a biophysical model implemented to study larval transport and environmental effects to assess the “environmental ratchet hypothesis” (ERH). We examined connectivity between areas of larval release and potential settlement. A sector of the middle domain on the shelf to the east of the Pribilof Islands showed consistent potential for larval retention, but reproductive females have virtually vanished there. Larvae hatched to the north and northwest of the islands, particularly in the outer domain are likely to be advected away. As the range of the female reproductive stock shifted northwards, its abundance declined following a regular 7-year cycle. Because mature females experience an offshore ontogenetic migration, those hatching larvae in the middle domain become “primipara”, spawning for their first time ca. 6 years past settlement. These results prompted the “contingent semelparity hypothesis”, according to which most of the effective reproductive contribution is made by the primipara in the middle domain, and the 7-year cycle results from the propagation of a sequence of strong year classes. This and ERH provide a mechanistic explanation for environmentally driven changes in the distribution and abundance of the stock with implication for the fishery.
Rescaling fisheries assessment and management: access privileges, responsibilities, and toolboxes (invited talk, Tuesday morning)
Jeremy Prince (Biospherics P/L, South Fremantle, Western Australia)
According to the collective experience of Hilborn, Orensanz and Parma one of the three primary causes for unexpected failure in fisheries is the mismatch between the scale of fished populations, and the scale of their assessment and management. Developed initially through my doctoral studies of abalone (haliotids) but cemented through subsequent experience with fisheries for lobster, penaeid prawns, deepwater teleosts, sharks and marine mammals my bias promotes the "tyranny of scale" to the top of Hilborn et al.’s list. Early in my career while still working within the constraints of a fisheries agency the challenge of assessing and managing a world filled with micro-stocks seemed insurmountable. However, after almost thirty years working on the interface between fishing communities and government agencies I believe solutions are in sight. Solving the issue of sustaining spatially complex marine resources requires:
- Cultivating the more human approach embodied by Johannes.
- Flexibly scaled social systems implemented and motivated with dedicated access privileges linked directly to the
- Responsibility to fish for data as well as profit.
- A new breed of fisheries practitioners; barefoot ecologists, pragmatic generalists armed with
- A toolbox full of generic pragmatic approaches; flexible survey designs, scale-less assessment techniques, data-less or rule-of-thumb management prescriptions, and software tools for mapping, modeling and visualization.
Where have all the big fish gone? Distribution of remaining large reef fishes in the Hawaiian archipelago (contributed talk, Wednesday morning)
Benjamin L. Richards, Emily R. Lundblad, Brian J. Zgliczynski, Marc O. Nadon, Robert E. Schroeder, and Russell E. Brainard (NOAA/JIMAR Pacific Islands Fisheries Science Center, Honolulu, Hawaii)
This study represents one of the first and most comprehensive efforts
to investigate habitat preference of large-bodied reef fishes (>50 cm
TL) in the Hawaiian Archipelago. Physical characteristics of coral
reefs including depth, slope, rugosity, and habitat type have been
shown to play a critical role in the distribution of many reef fishes.
However, research has generally focused on small spatial scales and on
species living in tight association with the reef (e.g.,
Chaetodontidea, Pomacanthidea, etc.). While it stands to reason that
similar relationships should exist, little work has focused on similar
large-scale habitat parameters and larger-bodied reef fishes (e.g.,
Carcharhinidea, Carangidea, etc.) many of which contribute to the
highest trophic levels, are wide ranging, and are most vulnerable to
exploitation, habitat degradation and ecosystem change. In this study,
distributions of large-bodied reef fish were analyzed from over 700
surveys (2000-2006) covering ~1500ha of coral reef habitat with
respect to depth, slope, rugosity and habitat type using a GIS
framework. Bathymetric data were derived from in-situ observations and
multibeam sonar surveys. Habitat type was determined using published
benthic habitat maps. Initial analyses support earlier research
showing dramatic differences in large fish populations between the
Main and Northwestern Hawaiian Islands. Significant correlation was
found between biomass of large reef fishes and habitat parameters
including depth, slope, and rugosity. These results provide a basis
for efficient and targeted management strategies, begin to define
essential fish habitat for these species, and lay the foundation for
similar investigations across the Pacific Region.
Beyond ocean zoning: the economics, ecology, and legal framework of ocean protection (invited talk, Tuesday morning)
James N. Sanchirico, Josh Eagle, Stephen Palumbi, and Barton H. Thompson (University of California, Davis)
Ocean zoning arguments often center on the biology of ocean species and the geography of fishing use patterns. Here we expand this discussion to the social and legal aspects of ocean zoning, focusing on comprehensive planning and segregation of activities into use-priority areas. These features can be a catalyst for a variety of ancillary benefits, including opportunities for user groups to form informal or formal long-lived institutions via better defined spatial-access privileges and a reassessment of the focus and scope of the regulatory institutions involved in ocean management. Both features will lead to improved conflict resolution, efficiency of use, and ecosystem stability-critical components for the production of ecosystem services and maintenance of biological and human economic benefits.
Empirical analysis of fine-scale spatial behavior and fishing strategies in the Baja California lobster fishery (contributed talk, Thursday afternoon)
Geoffrey Shester (Stanford University, Pacific Grove, California)
The spatial behavior of fishing fleets is one of the most important processes in fisheries management, though our understanding is still in its infancy. The dynamic process of sampling the environment and allocating fishing effort can have a profound impact on the sustainability of target species populations, impacts to the marine environment, distribution of revenue among fishermen, effectiveness of spatial regulations such as marine protected areas, and the utility of catch per unit effort data in stock assessments. In collaboration with fishing cooperatives, we instituted a pilot logbook and observer program with 15 red spiny lobster (Panulirus interruptus) fishing teams where trap locations, catch, and trap movement were recorded daily with GPS, resulting in a large database of over 18,000 individual decisions. Using Geographic Information System analysis, we analyze spatial patterns of fishing effort and catch rates, and characterize individual and collective fishermen behavior using a variety of spatial statistic techniques. By comparing the predicted distribution of lobsters based on catch levels with trap placement decisions, we are able to quantify search behavior and test predictions of optimal foraging theory such as the ideal free distribution on a fine spatial scale in the tens of meters. We also explore the utility of spatial zoning to improve the catch efficiency. Combined with at-sea interviews with fishing captains and anecdotal observations, we explain the observed patterns in fleet dynamics and illustrate how such spatial data can be used for a variety of empirical and policy applications.
Spatial zoning to reduce by-catch in commercial fisheries (YI poster, Thursday afternoon)
Geoffrey Shester (Stanford University, Pacific Grove, California)
By-catch, or the unintended catch of undesirable species, is a major conservation concern due to its potential population and ecosystem level impacts. By-catch rates vary by fishery and several approaches have been used to reduce by-catch, including incentives, gear modifications, and area closures. Here, we propose and test a novel approach for reducing by-catch using a spatial zoning approach that capitalizes on differences in catch composition among discrete fishing patches. We test the model in a case study community-based fishing cooperative in Mexico where we conducted a pilot observer program of the set gillnet fishery throughout the 2006 fishing season. We analyze observed catch records using a multivariate statistical approach to delineate discrete zones of based on species composition. Our model calculates the catch of all species resulting from different allocations of effort across zones, and outputs the optimal allocation of fishing effort in a multiple-species context where each species has a distinct market price. Construction of a production possibility frontier reveals all possible trade-offs between profits and by-catch reduction using our approach, and illustrates the most cost-effective management measures to achieve any desired level of bycatch reduction. We conclude by discussing ways to implement model results in fishery management policy and compare spatially-explicit effort limits to area closures in the context of by-catch. Such an approach shows the value of spatially explicit observer data for reducing by-catch and is highly applicable to small- and large-scale fisheries where by-catch poses a conservation concern.
Development of a GIS tool for displaying spatially explicit trophic bibliographic information on Gulf of Mexico fishes (poster, Wednesday morning)
J. D. Simons,1 J. Wood,2 and M. E. Vega-Cendejas3 (1Texas Parks and Wildlife Department, Corpus Christi, Texas; 2Texas A&M University, Corpus Christi, Texas; 3Unidad Merida, Merida, Yucatan, Mexico)
In recent years there has been the development of a plethora of biodiversity related databases for various taxonomic groups (i.e., FishBase, ORNIS, HerpNet, FishNet, EOL) or for different biospheric realms (i.e., OBIS). While the continued documentation of biodiversity data is extremely important, we are forgetting to catalog the links that hold this diverse fauna together in ecosystems. We report on the development of a bibliography of studies that catalogs the trophic links among fishes and their foods in the Gulf of Mexico and a GIS tool to display information from the bibliography. Through a graphical user interface, locations of studies by author, dates, species name (Latin or common) can be displayed. Furthermore, for a particular study, a list of species examined, or the number of records for a species examined, can be displayed. In addition, where data is available, the relationship of the species food habits studies to their spatial population distribution can be assessed. This bibliography and GIS tool are currently under final development and will be published by US Sea Grant in the near future. This project is the lead effort toward development of a comprehensive database of all recorded trophic interactions in the Gulf of Mexico, from crustaceans to marine mammals.
Toward a microbehavioral foundation for ecosystem-based management (invited talk, Thursday morning)
Martin D. Smith (Duke University, Durham, North Carolina)
Policy makers lack empirical information on the environmental dependence of fishery resources, spatio-temporal patterns of fish abundance, and the behavioral responses of the harvest sector to spatially explicit policies. Moreover, the specter of a changing climate accentuates these empirical difficulties.This paper explores the extent to which haul-level fishing micro-data can reveal properties about large-scale ecosystems and the environmental dependence of fisheries. Large-scale ecosystem models can be top down or bottom up, but both general approaches tend to focus on the bio-physical system. In contrast, this paper presents a bottom-up approach that focuses on human behavior as a means to learn about a complex ecosystem under changing climate.
The paper analyzes fishing micro-behavior with an econometric model of fishing location choice that allows for individual vessel heterogeneity. The model estimates spatio-temporal abundance indices non-parametrically from behavioral data. These indices then can quantify bottom-up environmental processes that drive abundance. The structural dependence of spatio-temporal fish abundance on environmental variables provides a basis for exploring the effects of climate change on the entire coupled system. By simulating the effects of climate change on environmental variables, the resulting effects on abundance and fishing behavior can be traced back up the system. This allows managers to consider how climate change could influence patterns of fishing behavior and, in turn, how climate-resilient spatial management such as MPAs could be designed. The paper illustrates the approach using simulated data and a series of Monte Carlo analyses.
Collection of bivalve postlarvae to test an “order zero” Connectivity model in the mortheastern Gulf of California, Mexico (YI poster, Wednesday afternoon)
Gaspar Soria,1 Ivan Martínez,2 William Ludt,1 William Shaw,1 and Richard Cudney-Bueno1,3 (1University of Arizona, Tucson, Arizona; 2Intercultural Center for the Study of Deserts and Oceans, Sonora, México; 3The David and Lucile Packard Foundation, Los Altos, California)
The Gulf of California harbors industrial and small-scale fisheries. These fisheries are socially and economically relevant for the region, but sustainability of marine resources is gaining more attention from managers, scholars and fishermen themselves. The diminishing supply of shellfish stocks led fishermen from Puerto Peñasco (PP), a fishing town located in the Northeastern side of the Gulf, to collectively establish, monitor, and enforce a network of “no take” areas in an effort to recover the declining stocks. An “order zero” model of particles’ transport for larvae dispersal resulting from advection by currents and turbulent diffusion was developed for the Northern Gulf. The model represents different hypothetical scenarios for passive larvae dispersion. For the area of PP, the model forecast that throughout the summer the connectivity is always cyclonic, while it is basically null in the opposite direction. If larvae abundance/distribution is driven by currents, a gradient of spat abundance matching the cyclonic circulations must be expected. To test this gradient we deployed bivalve larvae collectors in 6 sites throughout the fishing area of PP. Collectors were retrieved and replaced every 2 months, throughout 14 months. Seven commercial bivalve species were found. Each species showed a particular gradient of relative abundance among sites, and depths. Preliminary results on these gradients are presented and discussed. For establishing management and conservation guidelines, the analysis of other sources of information (biophysical and fishery data) is critical to fully understand the connectivity among sites in the area of PP.
Mapping the by-catch seascape: multi-species and multi-scale spatial patterns of fisheries bycatch (contributed talk, Thursday afternoon)
Candan U. Soykan, Rebecca L. Lewison, and Janet Franklin (San Diego State University,
San Diego)
Fisheries bycatch is a conservation issue for fisheries worldwide. Despite a growing awareness of by-catch problems in particular ocean regions, there have been few efforts to identify spatial patterns in by-catch events. Furthermore, many studies of fisheries by-catch have been myopic, focusing on a single species or a single region. Using a range of analytical approaches to identify spatial patterns in by-catch data, we demonstrate the utility and applications of area and point pattern analyses to single and multi-species bycatch seascapes in the Atlantic and Pacific Oceans. We find clear evidence of spatial clustering within species in both ocean basins, both in terms of the underlying pattern of where by-catch events occur relative to fishing locations and for areas of high by-catch rates. Furthermore, we find significant spatial overlap in the pattern of by-catch across species relative to the spatial distribution in fishing effort and target catch. These results point to the importance of considering spatial patterns of both single and multi-species by-catch to meet the ultimate goal of reducing by-catch encounters. These analyses also highlight the relevance of considering bycatch relative to target catch as a way of identifying areas where fishing effort reduction may help to reduce multi-species by-catch with minimal impact on target catch.
A novel Bayesian methodology for making the nost of spatial catch and effort data (YI contributed talk, Wednesday morning)
Aaron D. Springford and Sean P. Cox (Simon Fraser University, Burnaby, British Columbia)
Fisheries monitoring programs increasingly require precise measures of fishing location. However, much important spatial information is subsequently ignored in stock assessments. Instead, most assessments "standardize" the spatial data into aspatial indices of abundance using generalized linear models (GLMs). It is well-known that such aspatial CPUE indices make two tenuous assumptions: (1) the dimensional assumption - harvesters are random samplers so that average annual CPUE is proportional to average density over the range of the stock and (2) the independence assumption—residual errors in CPUE are independent after accounting for known covariates. Both assumptions are almost surely violated in every fishery in the world. In this paper, we describe a hierarchical Bayesian methodology for modeling spatial catch and effort data. The spatial model is used to derive indices of average stock density and commercially exploitable range (km2) that are more robust to departures from aspatial GLM assumptions. Application of the spatial model to British Columbia (BC) sablefish (Anoplopoma fimbria) stock assessment results in less optimistic estimates of population parameters compared to traditional stock assessment based on aspatial GLM abundance indices; optimum exploitation rate and yield estimates from the spatial analysis are 21% and 22% lower, respectively. The same spatial analysis estimates the commercially exploitable range of BC sablefish to have decreased by 41% over the period 1990-2005.
Fisheries plays within an ecosystem theater: challenges of managing ecological and social drivers of marine fisheries at multiple scales (invited talk, Wednesday afternoon)
Robert S. Steneck and James A. Wilson (University of Maine, Walpole)
The scale at which fisheries biological and social structures operate vary considerably. Ecosystem integrity hinges on temporally and spatially explicit processes driven by productivity, habitat and climate. The resulting geographic hierarchy of gamma, beta and alpha diversity is evident in nested biogeographic provinces, metapopulations and demes. Similarly, competition among fishers creates self-organizing spatial social patterns but these rarely parallel the ecological scales. Clearly, no set of boundaries can perfectly capture the distribution of organisms within an ecosystem and the social structure that has co-evolved with them. We use three fisheries representing three phyla (gadoid groundfish, urchins and lobsters) in the Gulf of Maine to illustrate the difficulties and prospects for spatially defined ecosystem-based management. Each species or group has different spatial attributes. We describe how fishing led to the decline of gadoids and sea urchins. We speculate that normal competitive processes among fishers leads to spatially unconstrained overfishing also called “roving bandits”. In contrast, self-organizing competitive processes in the lobster fishery constrain the spatial movement of fishers and generate feedback that makes the evolution of local forms of governance feasible, resulting in a multi-scale, sustainable system of governance.
The ecological footprint of fishing gear types in relation to by-catch levels: lessons learned for the mitigation of by-catch of seabirds, marine mammals, and sea turtles (poster, Wednesday morning)
Kelly Stewart,1 Rhema Bjorkland,1 Daniel Dunn,1 Shaleyla Kelez,1 Rebecca Lewison,2 Wallace J. Nichols,3 and Lesley Thorne1 (1Duke University Marine Laboratory, Beaufort, North Carolina; 2San Diego State University, San Diego, California; 3Ocean Conservancy & California Academy of Sciences, Davenport, California)
Quantifying effects of fisheries on by-catch of sea turtles, seabirds, and marine mammals is critical to conservation for these taxa. Because of the high variability in gear types, oceanographic variables, targeted species, fishing effort among regions and social/political challenges, this has been an elusive goal. Although progress has been made to understand the magnitude of the problem, the urgency to solve these problems is greater than ever as our oceans are coming under increasing pressure. Coastal zones represent areas of specific concern as much of global fishing effort is concentrated here. As a result of our comprehensive compilation of international fishing effort data, we have derived informative metrics of fishing effort for three gear types - gillnets, longlines and trawls. With these metrics, as well as with specific spatial data collected on ports, distances that fishers travel from port to fish, bottom depth in the area where they fished, and temporal variables (days fished, seasons, etc.), we created maps to consider spatial patterns of fishing effort, particularly in coastal zones. These maps and related fisheries bycatch information ranks areas relative to their by-catch impacts on seabirds, marine mammals, and sea turtles. Results focus on differences in ecological impacts across gear types and highlight countries or regions that have actively (or inadvertently) reduced these impacts. We report on important lessons learned about where bycatch reduction has been effective and areas in which bycatch reduction is still critical for the recovery and protection of seabirds, marine mammals, and sea turtles.
The Chilean TURF system for small scale benthic fisheries: the match and mismatch of scales (contributed talk, Tuesday afternoon)
W. Stotz, J. Aburto, L. Caillaux, D. Lancellotti, M. Valdebenito, M. Escobar, F. Cecchi, R. Garay-Flühmann, and S. Zuñiga (Universidad Católica del Norte, Coquimbo, Chile)
The extensive implementation of a TURF system, called “Áreas de Manejo y Explotación de Recursos Bentónicos” (AMERB), which started formally in 1997 in Chile, gave rise to profound changes in small scale benthic fisheries. Conferring exclusive fishing rights to, and complementarily, restricting former migrations of artisanal fishermen along the coast, may have effects within the environmental, productive, social, economic and institutional context. Each of the variables associated to each of these contexts, has its own dynamic, within its own spatial and temporal scale. Theoretically, the match or mismatch of scales of the diverse variables may produce differing results of AMERBs. This is analyzed in the context of 50 AMERBs along a stretch of ca. 500 Km of coast in north-central Chile. A predominance of unsatisfactory results is observed, with the benefits of the TURF system being questioned by fishermen. The temporal and spatially variable, and mostly insufficient income, produced by variations of the natural production and the lack of alternatives to survive during bad periods, are identified as the main reasons. Options to improve the system require the removal of incentives to enter and adhere to the system, especially in cases when it is not working.
Analyzing movement behavior and habitat use of common snook in Sarasota Bay, Florida (poster, Wednesday afternoon)
Juliane Struve,1 Kai Lorenzen,1 Lauren Marcinkiewicz,2,3 Janet Gannon,2 Nathan Brennan,2 William Pine,3 and Jason Bennett3 (1Imperial College London, UK; 2Mote Marine Laboratory, Sarasota, Florida; 3University of Florida, Gainesville, Florida)
Common snook (Centropomus undecimalis) is a popular game fish in Florida, managed through stringent harvest regulations, a pilot scale stock enhancement program and some habitat restoration initiatives. The euryhaline species utilizes coastal, estuarine and freshwater habitats in the course of its lifecycle. We use biotelemetry data in conjunction with a GIS-based habitat map to analyze movement behavior of snook and its relation to habitat features in Sarasota Bay, Florida. A total of 103 adult snook were fitted with ultrasonic transponders and their movement monitored by 36 VEMCO automated ultrasonic receivers positioned around the Bay. Initial analysis of the minimum distances travelled during the total recording period suggests that adult snook travel at a rate of 600-1200 m/day and that the movement rate is not related to body size. Low movement rates were found close to mangrove habitats, whereas high movement rates were found within creeks and within passes. Some individuals remained in creek habitats throughout, whereas others preferred mangrove shores or passes. High individual movement rates are not necessarily associated with a high net longitudinal displacement of an individual from its location of release. Movements of snook may be described as a combination of faster movements with a persistent direction and slower movements and longer stays in preferred habitats. We use movement models to predict the spatial distribution of snook, and discuss implications of movement and distribution patterns for harvest regulation, habitat restoration and stock enhancement.
Historical reconstruction and evaluation of management strategies for the Washington state geoduck (Panopea abrupta) fishery (YI contributed talk, Thursday afternoon)
Juan L. Valero,1 Ana M. Parma,2 J. M. (Lobo) Orensanz,2 and Ray Hilborn1 (1University of Washington, Seattle; 2Centro Nacional Patagónico, CONICET, Chubut, Argentina)
The longevity and slow-paced dynamics of geoduck clams (up to 168 yrs) may lead to perceptions of stock stability and fisheries sustainability that can be more apparent than real. The Washington state geoduck fishery uses a harvest rate of 2.7% (based on F40%) to set quotas as a fraction of the surveyed biomass in each of five management regions. Quotas are implemented using a rotation strategy, in which a number of tracts are pulse-fished per year. Harvested tracts cannot be reopened until abundance recovers to pre-harvest levels (recovery proviso). Only a fraction of tracts are surveyed annually and quotas are calculated using the last available survey for each tract, assuming no change since the last survey except for catches. Heterogeneous patterns in recruitment and natural mortality in time and space challenge the use of reference points and the validity of not updating the estimated abundances. We evaluated the sustainability of the current harvest strategy using a simulation model describing the dynamics of geoduck populations, their fishery and management. We reconstructed historical series of biomass, recruitment and catches using age, abundance and landings data. Results suggest that assuming no change in biomass for not-surveyed tracts underestimates the actual biomass. Prior to the introduction of regional quotas in 1994 realized harvest rates differed markedly among regions, departing substantially from the target. Simulation results show that the recovery proviso is a key risk-averse element of the current harvest strategy. Performance could improve by adjusting target harvest rates to reflect regional differences in productivity.
The scale, structures, and resources involved in exploiting and managing decapod crustacean fisheries in Norway: correspondence between status of the fisheries, the value, and investments in the management (poster, Wednesday afternoon)
Gro I. van der Meeren and Guldborg Søvik (Institute of Marine Research, Bergen, Norway)
In 2005 the concept of ecosystem-based management of marine resources was introduced in Norway. Preparations for implication are in progress and will involve decapod crustacean fisheries. Fisheries for crustaceans in Norway goes back to the mid-1650’s, when fisheries for European lobster (Homarus gammarus, Linneus, 1758) was initiated. It has since developed to coastal and off-coast fisheries from the North Sea to the Barent Sea, for lobsters, edible crabs (Cancer pagurus, Linneus, 1758), shrimps (Pandalus borealis, Krøyer, 1838), Norway lobsters (Nephrops norvegicus, Linneus, 1758), and lately, the introduced red king crabs (Paralithodes camtschaticus, Tilesius, 1815). The wide geographical scale of the fishing grounds, traditions, and often weak databases has led to separate management regimes of and highly variable sustainability for these fisheries. An overview over the present-day fisheries and management are presented; the size and quality of the fishing fleet, landings, the social impact and value of the fisheries, compared to investments in research, stock assessment, and management efforts. How culture, tradition, and research have led to the present status of these fisheries is discussed and compared to international crustaceans and finfish fisheries. There is little correspondence between the values of these biological resources (both ecologically and economically) and the efforts and investments put into the management. The new management approach must be founded on appreciation of biological and ecological data, insight in the ecosystem each species is part of, and a true understanding of the value of these fisheries and the social implications they make along the Norwegian coast.
Model-based geostatistical methods for obtaining spatially explicit abundance from fisheries data (contributed talk, Wednesday morning)
J. F. Walter III,1 J. M. Hoenig,2 and M. C. Christman3 (1NOAA Southeast Fisheries Science Center, Miami, Florida; 2Virginia Institute of Marine Science, Gloucester Point, Virginia; 3University of Florida, Gainesville, Florida)
Spatially explicit fisheries management compounds the difficult task of determining how many fish are out there by adding the further requirement of determining how many fish are at specific locations. This task greatly increases both the amount of information needed and requires the use of model-based survey approaches that can extend predictions into unsampled locations. Fortuitously, the need for more precise spatial information coincides with increases in both the volume and precision of catch and effort data collected onboard commercial fishing vessels. Data from onboard observers and vessel monitoring systems provide a rich set of observations from which to obtain catch rates and relative abundances of both target and bycatch species. We discuss methods of incorporating commercial catch data into geostatistical abundance estimates and demonstrate how geostatistical tools utilize spatial autocorrelation in the prediction process, reduce the influence clustered and targeted observations and extend our inference into unsampled locations. We provide several examples with applications ranging from the prediction of sea scallop abundance to estimation of bycatch rates.
Representation of multistanza life histories in Ecospace models for spatial organization of ecosystem trophic interactions (contributed talk, Wednesday afternoon)
C. J. Walters,1 V. Christensen,1 W. Walters,2 and K. Rose3 (1University of British Columbia, Vancouver; 2University of Florida, Gainesville; 3Louisiana State University.Baton Rouge)
The Ecospace model for spatial organization of trophic interactions has seen limited use for evaluation of policies such as marine protected areas, partly because of concern about representing key indicator populations only by spatial biomass distributions. The software has been improved to include spatial representation of age structure for such species, using the Ecosim “multistanza” population submodel that assumes similar diet compositions, predation risk, and vulnerability to fishing over blocks or stanzas of fish ages. A computationally efficient version of Ecospace now preserves the multistanza age structure over spatial habitat and ecosystem biomass maps, evaluating body growth and mortality rates as spatial averages weighted by relative biomass use of each model spatial cell. A computationally intense version divides each multistanza population into spatial packets (an Indiviual-Based Model, IBM approach) for more precise analysis of how movement patterns and movement histories over mosaics of trophic opportunities and risks may impact on population performance and variability. The two approaches give surprisingly similar predictions of abundance patterns over both time and space, agreeing well in case study applications to the Gulf of Mexico and California coast with non-spatial Ecosim predictions and with each other.
One size does not fit all (YI contributed talk, Thursday afternoon)
Jono Wilson )University of California, Santa Barbara)
Nearshore rocky reef fishes and invertebrates display high degrees of demographic variability over relatively small spatial scales. Observed differences in demographic rates such as growth parameters, natural mortality and age or size at maturity can have profound impacts on the potential egg production and yield of local populations. Current stock assessments and minimum legal size limit regulations for US west coast fisheries do not typically account for this spatial variability both due to limitations of modeling capability and the lack of available resources to manage at fine scales. However, the resulting effects of ignoring this spatial variability can contribute to localized over and underfishing. To demonstrate the ubiquity of spatial variation in demographic rates in US west coast fisheries, I compiled published data on growth rate parameters, natural mortality and size/age at maturity for a number of species in which this variability is not specifically accounted for in stock assessment models nor in the setting of minimum legal size limits. To examine the effects of this spatial variation on harvestable yield and egg production, age structured equilibrium models were built for several selected species. Yield per recruit and spawning potential ratio isopleths were constructed using exploitation patterns set with a single minimum size limit versus a minimum size limit adjusted to local demographic parameters. Results confirm that simple actions such as adjusting minimum size limits to local scale demographic rates may have the potential to improve egg production while simultaneously increasing yield for a number of harvested species.
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Florida State University,
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