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At least 37 records · Page 2Linked to original sources
USGS2007

Issues, benefits, and problems associated with fishing tournaments in inland waters of the United States: A survey of fishery agency administrators

A web-based survey was administered to state fisheries agency administrators in 2005 to assess and prioritize the impacts of tournament fishing on management of inland fishery resources. Surveys were completed by fishery administrators of 48 state agencies and the District of Columbia. Respondents rated tournaments as neither strongly benefiting nor adversely affecting fishery management. Benefits of tournaments to fishery management grouped into four factors (in order of decreasing impact) characterized as enhancing fishery management agency effectiveness, stimulating interest in fishing and fishery resources, measuring economic value, and collecting biological information. Adverse impacts grouped into six factors (in order of decreasing impact), characterized as resource crowding, user-group conflicts, costs of tournaments to fishery agencies, non-traditional uses of fisheries resources, fish introductions, and adverse affects on fish populations. Tournament issues and impacts generally did not differ regionally and suggested the effects of tournaments do not vary among different fisheries. Comparison with previous surveys indicates that the prevalence of some benefits and problems have changed since 1989. Social issues remained paramount problems, but biological impacts were considered a lesser problem. Agencies recognized that tournaments can benefit fisheries management efforts and angler recruitment. Future management of tournaments should consider a management team approach.

Fisheries↗
USGS2024

Adaptive capacities of inland fisheries facing anthropogenic pressures

Inland fisheries face multiple, intensifying threats (i.e., proximate human pressures causing degraded ecological attributes) from land development, climate change, resource extraction, and competing demands for water resources. Planning for resiliency amidst these pressures requires understanding the factors that influence an inland fishery’s capacity to adapt to system changes under multiple threats. Incorporating expert knowledge can illuminate priority fisheries and provide important insights where data are otherwise limited. Using data from a global survey of 536 fishery professionals, this study examines perceptions of threats and adaptive capacity (i.e., ability to mitigate or respond to change) in major inland fisheries. We assessed associations across 29 different perceived threats and their ranked influence scores, tested agreement among five adaptive capacity domains (i.e., agency, assets, flexibility, learning, organization), and examined relationships between threats and adaptive capacity domains. Results provide quantitative evidence that the greatest threats to inland fisheries come from outside the fishing sector and that most inland fisheries face multiple threats. Results also support the five domains as a collective measure of adaptive capacity and illuminate a negative association between the threats to a fishery and a fishery’s adaptive capacity. These findings highlight the need for fishery managers to engage in decision making with non-fishery sectors (e.g., multi-sectoral management) and the prioritization of habitat and watershed-scale conservation and rehabilitation efforts for improved adaptability amidst ecological transformation.

Global Environmental Change↗
USGS2019

Characterizing angler preferences for Largemouth Bass, Bluegill, and Walleye fisheries in Wisconsin

Managing recreational fisheries in lake-rich landscapes with diverse fish communities and anglers alike presents a social and biological challenge for managers. Understanding angler preferences is central to navigating these challenges and can aid in predicting shifts in angler behavior in response to management actions or changing fish populations. Species-specific angler surveys do not incorporate tradeoffs inherent in multispecies fisheries, thus limiting their application to real-world management issues. To better understand angler preferences in relation to realistic tradeoffs among different fishing opportunities, we conducted a survey of Wisconsin anglers in 2013–2014 that included questions requiring anglers to choose between fisheries providing different outcomes. We used stated-preference modeling to quantify angler preferences associated with Bluegill Lepomis macrochirus , Largemouth Bass Micropterus salmoides , and Walleye Sander vitreus fisheries. Next, we conducted a latent class analysis using survey responses to classify anglers into subgroups. Finally, we assessed the sensitivity of angler choice to changes in fishing opportunities. Results of the stated-preference models indicated that both residents and nonresidents largely prefer “quality” (i.e., moderate catch rate and size structure) over “action” or “trophy” Bluegill fisheries and that characteristics of Largemouth Bass fisheries have more value to nonresidents than to residents. Aspects of the Bluegill fishery were most important in choosing among hypothetical lakes for resident respondents. Five angler subgroups were identified that show the importance of Bluegill and Walleye but shed additional light on anglers’ commitment level and nonresidents’ preference for Largemouth Bass. In addition, simulations of changes in Walleye, Largemouth Bass, and Bluegill fisheries indicated that maintenance of quality Bluegill fisheries is important to ensuring continued angler participation, while the retention of high-yield Walleye fisheries is likely paramount to a subgroup of anglers. Our results offer insight into angler preferences across the lake-rich landscape of Wisconsin and demonstrate how angler behavior may shift in response to transitions in fishing opportunities.

Wisconsin↗
USGS2017

Assessing the global distribution of river fisheries harvest: A systematic map protocol

Background Although surface freshwater comprises < 0.01% of the total water volume of earth, freshwater inland capture fisheries and aquaculture represent 40% of the global reported finfish harvest. While the social, economic, and ecological importance of inland fish and fisheries is difficult to overstate, they are often undervalued and underappreciated. Accurate information about these highly dispersed fisheries is inherently difficult to acquire, often unreported, and not collected in a standardized format globally. A standardized river fishery database is needed for managing aquatic systems as well as for defining relevant development policies. Here, we describe our methodology to search, identify, and describe available river fisheries information to create a harmonized global database of river fisheries harvest. This database will provide the first global database of spatially and temporally explicit river fisheries data. The database can be used to identify locations, hotspots of data collection, and gaps in existing knowledge and will be especially important to inform studies and management at larger spatial scales (i.e., watershed, regional, or global scales). This database will also be critical for developing fish biomass models for rivers, which can provide managers with information critical for decision-making, such as improved valuation methods for river fish and fisheries. Methods This systematic map protocol describes the methodology to search, identify, and describe available information on river fish and fisheries across the globe. We define river fisheries as “both capture and aquaculture of river finfish species for food, income, or recreation”. River fish species are those finfish that live part, or all of their lives in rivers. The searches will be conducted for the period from 1950 to present using bibliographic databases and grey literature sources. To identify relevant evidence, pre-defined inclusion and exclusion criteria will be used to screen articles at title, abstract, and full text. A searchable database containing extracted meta-data from relevant included studies will be developed and presented as a geodatabase. The final systematic map will consist of a descriptive narrative report of the distribution and content of river fish literature including a geodatabase of available information.

Environmental Evidence↗
USGS2021

A bright spot analysis of inland recreational fisheries in the face of climate change: Learning about adaptation from small successes

Inland recreational fisheries have social, economic, and ecological importance worldwide but these fisheries are increasingly challenged by the diverse effects of climate change. Coupled with other anthropogenic stressors, climate change has contributed to declines in freshwater biodiversity of greater severity than those observed across marine or terrestrial taxa. At a macro level, inland fisheries are experiencing declines. There are, however, a number of success stories, or ‘bright spots,’ in inland recreational fisheries management, where innovative approaches are leading to increases in social and ecological well-being in the face of climate change. Cases such as these are important sources of inspiration and learning about adaptation to climate and environmental change. In this article, we analyze 11 examples of such ‘bright spots’ drawn from multiple jurisdictions around the world from which we extracted lessons that might apply to fisheries management challenges beyond the region and context of each case. Collectively, these bright spots highlight adaptive initiatives that allow for recreational fisheries management to mitigate to stressors associated with current and future climate change. Examples identified include community-based restoration projects, collaborative and adaptive approaches to short-term fisheries closures, transdisciplinary large-scale conservation projects, and conservation-minded efforts by individuals and communities. By highlighting examples of ‘small wins’ within inland recreational fisheries management, this review contributes to the idea that a ‘positive future’ for inland recreational fisheries in the face of climate change is possible and highlights potential strategies to adapt to current and future climate scenarios.

Reviews in Fish Biology and Fisheries↗
USGS2012

Benefits and risks of adopting the global code of practice for recreational fisheries

Recreational fishing constitutes the dominant or sole use of many fish stocks, particularly in freshwater ecosystems in Western industrialized countries. However, despite their social and economic importance, recreational fisheries are generally guided by local or regional norms and standards, with few comprehensive policy and development frameworks existing across jurisdictions. We argue that adoption of a recently developed Global Code of Practice (CoP) for Recreational Fisheries can provide benefits for moving recreational fisheries toward sustainability on a global scale. The CoP is a voluntary document, specifically framed toward recreational fisheries practices and issues, thereby complementing and extending the United Nation's Code of Conduct for Responsible Fisheries by the Food and Agricultural Organization. The CoP for Recreational Fisheries describes the minimum standards of environmentally friendly, ethically appropriate, and—depending on local situations—socially acceptable recreational fishing and its management. Although many, if not all, of the provisions presented in the CoP are already addressed through national fisheries legislation and state-based fisheries management regulations in North America, adopting a common framework for best practices in recreational fisheries across multiple jurisdictions would further promote their long-term viability in the face of interjurisdictional angler movements and some expanding threats to the activity related to shifting sociopolitical norms.

Fisheries↗
USGS2016

To manage inland fisheries is to manage at the social-ecological watershed scale

Approaches to managing inland fisheries vary between systems and regions but are often based on large-scale marine fisheries principles and thus limited and outdated. Rarely do they adopt holistic approaches that consider the complex interplay among humans, fish, and the environment. We argue that there is an urgent need for a shift in inland fisheries management towards holistic and transdisciplinary approaches that embrace the principles of social-ecological systems at the watershed scale. The interconnectedness of inland fisheries with their associated watershed (biotic, abiotic, and humans) make them extremely complex and challenging to manage and protect. For this reason, the watershed is a logical management unit. To assist management at this scale, we propose a framework that integrates disparate concepts and management paradigms to facilitate inland fisheries management and sustainability. We contend that inland fisheries need to be managed as social-ecological watershed system (SEWS). The framework supports watershed-scale and transboundary governance to manage inland fisheries, and transdisciplinary projects and teams to ensure relevant and applicable monitoring and research. We discuss concepts of social-ecological feedback and interactions of multiple stressors and factors within/between the social-ecological systems. Moreover, we emphasize that management, monitoring, and research on inland fisheries at the watershed scale are needed to ensure long-term sustainable and resilient fisheries.

Journal of Environmental Management↗
USGS2014

Impact of increasing market access on a tropical small-scale fishery

Small-scale fisheries have historically been marginalized in management and policy investments, and they often remain under-reported in national economic and fisheries statistics. Even so, small-scale fisheries are not entirely buffered from the impacts of globalization, such as the introduction and expansion of markets. This study measures the long-term impact of market-access on a coastal fishery on Nicaragua׳s remote Atlantic Coast from approximately the time when fishermen had access to stable and predictable local markets until the present, when the region has been transformed by road connection. In the last four years, fisheries trade has expanded as road connection has facilitated export to distant markets. Fishery-independent surveys were used to measure changes in indicators of fish-community status such as length-frequency, mean trophic level, and relative biomass. Species-level changes in relative biomass of common snook Centropomus undecimalis and gafftopsail catfish Bagre marinus were also evaluated since these species are the most economically valuable and likely account for the most fish biomass in the system. Using historical records, reports, current observations and interviews, changes in indicators of fishing intensity and market access over the past 17 years were assessed. From 1994 to 2011, community and species-specific metrics of the lagoon fishery declined significantly across all indicators examined. The potential social and economic outcomes of the decline in the fishery are far-reaching for the region, because this tropical fishery comprises the main source of protein and income for residents of twelve indigenous and Afro-descendent communities.

Marine Policy↗
USGS2024

Assessing and implementing the concept of Blue Economy in Laurentian Great Lakes fisheries: Lessons from coupled human and natural systems

Inland fisheries often receive little to no attention in global discussions about sustainable development. The consequences of overlooking inland fisheries in sustainability dialogues are increasingly problematic as fisheries stressors (e.g., overharvest, species invasion, climate change, habitat modification) intensify. Elevating the global profile of inland fisheries requires an approach for quantifying and clearly conveying the ecological, economic, and societal values of these systems. One such approach involves the Blue Economy, a multifaceted concept initially used to describe the intersection of marine conservation and sustainable use of marine resources for economic growth. Although conceptually powerful, the Blue Economy has rarely been applied to inland waters and fisheries. To address this knowledge gap, we conceptualized Laurentian Great Lakes fisheries from a Blue Economy perspective. In particular, we evaluated the utility of the coupled human and natural systems (CHANS) framework for characterizing the ecological, economic, and societal values of Laurentian Great Lakes fisheries and associated contributions to the Blue Economy (e.g., human livelihoods, food security, recreation, conservation, economic prosperity). There are numerous opportunities to leverage CHANS methods (e.g., metacoupling, telecoupling) and associated mathematical models to advance fisheries science, inform fisheries management, and ultimately move toward a Blue Economy in the Laurentian Great Lakes. To that end, we demonstrated applications of CHANS methods, discussed strategies for communicating with stakeholders, and provided insights for navigating challenges to developing a Blue Economy in the Laurentian Great Lakes—a model that could be used in the African Great Lakes and other large ecosystems in the world.

Laurentian Great Lakes↗
USGS2019

Back from the brink: Sustainable management of the Lake Erie walleye fishery

This chapter describes management actions implemented after a large-scale population decline of the Walleye Sander vitreus population in Lake Erie, one of the Laurentian Great Lakes in North America. Intensive fishery exploitation during the 1950s combined with declining water quality conditions collapsed the Walleye stock during the early 1960s. The fishery persisted at low levels until 1970 when the fishery was closed (1970–1972) due to elevated mercury concentrations in Walleye tissue. Lake Erie fishery managers at the time recognized the need for a coordinated, multi-agency approach to protect this ecologically, economically, and socially important resource. The harvest ban was lifted in 1973 when mercury levels dropped below advisory levels. In 1976, an interagency management framework was established, which relied on a coordinated, science-based management philosophy consisting of estimating safe harvest levels, performing applied research, and conducting annual population assessments. The population rebounded during the 1980s in response to improving environmental conditions, regulated harvest, and a series of strong recruitment events. Declines in harvest and population size were again observed during the late 1990s and mid-2000s, likely due to variation in natural processes controlling recruitment, and fishery managers enacted harvest practices during this period to promote long-term sustainability. Today, Lake Erie Walleyes support one of the largest self-sustaining freshwater fisheries in North America. Throughout the years, Lake Erie managers have iteratively adopted changes to their population assessment model and altered harvest policies to avoid future fishery and population collapses. More than 40 years later, Lake Erie continues to support commercial and recreational fisheries lake wide. Lessons learned from the stock recovery and subsequent coordinated management for fishery sustainability include the importance of conducting routine population assessments, using science-based research to address key uncertainties, adopting modern stock assessment approaches, incorporating stakeholder input into the quota setting process, and addressing environmental concerns collaboratively at the lake level.

Book chapter↗
USGS2017

Designing a global assessment of climate change on inland fishes and fisheries: knowns and needs

To date, there are few comprehensive assessments of how climate change affects inland finfish, fisheries, and aquaculture at a global scale, but one is necessary to identify research needs and commonalities across regions and to help guide decision making and funding priorities. Broadly, the consequences of climate change on inland fishes will impact global food security, the livelihoods of people who depend on inland capture and recreational fisheries. However, understanding how climate change will affect inland fishes and fisheries has lagged behind marine assessments. Building from a North American inland fisheries assessment, we convened an expert panel from seven countries to provide a first-step to a framework for determining how to approach an assessment of how climate change may affect inland fishes, capture fisheries, and aquaculture globally. Starting with the small group helped frame the key questions (e.g., who is the audience? What is the best approach and spatial scale?). Data gaps identified by the group include: the tolerances of inland fisheries to changes in temperature, stream flows, salinity, and other environmental factors linked to climate change, and the adaptive capacity of fishes and fisheries to adjust to these changes. These questions are difficult to address, but long-term and large-scale datasets are becoming more readily available as a means to test hypotheses related to climate change. We hope this perspective will help researchers and decision makers identify research priorities and provide a framework to help sustain inland fish populations and fisheries for the diversity of users around the globe.

Reviews in Fish Biology and Fisheries↗
USGS2016

Effects of consumption-oriented versus trophy-oriented fisheries on Muskellunge population size structure in northern Wisconsin

To determine whether a consumption-oriented fishery was compatible with a trophy-oriented fishery for Muskellunge Esox masquinongy , we modeled effects of a spearing fishery and recreational angling fishery on population size structure (i.e., numbers of fish ≥ 102, 114, and 127 cm) in northern Wisconsin. An individual-based simulation model was used to quantify the effect of harvest mortality at currently observed levels of recreational angling and tribal spearing fishery exploitation, along with simulated increases in exploitation, for three typical growth potentials (i.e., low, moderate, and high) of Muskellunge in northern Wisconsin across a variety of minimum length limits (i.e., 71, 102, 114, and 127 cm). Populations with moderate to high growth potential and minimum length limits ≥ 114 cm were predicted to have lower declines in numbers of trophy Muskellunge when subjected to angling-only and mixed fisheries at observed and increased levels of exploitation, which suggested that fisheries with disparate motivations may be able to coexist under certain conditions such as restrictive length limits and low levels of exploitation. However, for most Muskellunge populations in northern Wisconsin regulated by a 102-cm minimum length limit, both angling and spearing fisheries may reduce numbers of trophy Muskellunge as larger declines were predicted across all growth potentials. Our results may be useful if Muskellunge management options in northern Wisconsin are re-examined in the future.

North American Journal of Fisheries Management↗
USGS2016

Was everything bigger in Texas? Characterization and trends of a land-based recreational shark fishery

Although current assessments of shark population trends involve both fishery-independent and fishery-dependent data, the latter are generally limited to commercial landings that may neglect nearshore coastal habitats. Texas has supported the longest organized land-based recreational shark fishery in the United States, yet no studies have used this “non-traditional” data source to characterize the catch composition or trends in this multidecadal fishery. We analyzed catch records from two distinct periods straddling heavy commercial exploitation of sharks in the Gulf of Mexico (historical period = 1973–1986; modern period = 2008–2015) to highlight and make available the current status and historical trends in Texas’ land-based shark fishery. Catch records describing large coastal species (>1,800 mm stretched total length [STL]) were examined using multivariate techniques to assess catch seasonality and potential temporal shifts in species composition. These fishery-dependent data revealed consistent seasonality that was independent of the data set examined, although distinct shark assemblages were evident between the two periods. Similarity percentage analysis suggested decreased contributions of Lemon Shark Negaprion brevirostris over time and a general shift toward the dominance of Bull Shark Carcharhinus leucas and Blacktip Shark C. limbatus . Comparisons of mean STL for species captured in historical and modern periods further identified significant decreases for both Bull Sharks and Lemon Sharks. Size structure analysis showed a distinct paucity of landed individuals over 2,000 mm STL in recent years. Although inherent biases in reporting and potential gear-related inconsistencies undoubtedly influenced this fishery-dependent data set, the patterns in our findings documented potential declines in the size and occurrence of select large coastal shark species off Texas, consistent with declines reported in the Gulf of Mexico. Future management efforts should consider the use of non-traditional fishery-dependent data sources, such as land-based records, as data streams in stock assessments.

Texas↗
USGS2022

Overturning stereotypes: The fuzzy boundary between recreational and subsistence inland fisheries

Inland recreational fisheries provide numerous socio- economic benefits to fishers, families and communities. Recreationally harvested fish are also frequently consumed and may provide affordable and sustainable but undervalued contributions to human nutrition. Quantifying the degree to which recreationally harvested fish contribute to food security and subsistence is impeded by lack of data on harvest and consumption and by the difficulty in differentiating among recreational and subsistence fisheries. Recreational harvest records tend to be limited to wealthy, food- secure countries and well- monitored fisheries with clear regulations or permitting systems. These records often neglect components of recreational harvest among food- insecure fishers who are potentially more likely to have consumption as a motivation. Here, we highlight the ‘fuzzy boundary’ that can exist between inland recreational and subsistence fisheries and argue that unreported consumption is likely to be a hidden contributor to food security in some populations. We draw on local case studies from around the world to highlight specific instances where recreationally harvested fish species contribute food and subsistence benefits to participating communities. We use these examples to highlight the diversity of ways that inland recreational fisheries contribute to human nutrition, knowledge gaps in understanding recreational fishing for food, and consequences of not accounting for them as food fisheries in policy and management. The aim of this paper is to draw the attention of resource managers and policy makers, create greater social awareness of the importance of recreational fisheries and bring to light this hidden contribution of inland fisheries to nutrition and subsistence.

Northern Territory, Virginia↗
USGS2009

Maintaining the competitiveness of the American Fisheries Society journals: An assessment based on influence and cost-effectiveness

Recent changes in the landscape of scientific publishing prompted the Publications Overview Committee of the American Fisheries Society (AFS) to review the Society's portfolio of scientific journals. We evaluated journals based on metrics in two categories: (1) citation-based measures of the influence of a journal on the scientific literature, and (2) measures of the cost-effectiveness of a journal (citation rate adjusted for subscription cost). Over the long-term, we found that ecology journals had far stronger citation-based influence than fisheries and aquatic sciences journals, and that journals publishing primarily basic research had stronger influence than journals publishing applied research (including four AFS journals and Fisheries magazine). In evaluating the current status of fisheries and aquatic sciences journals, we found that metrics of influence and cost-effectiveness provided considerably different portrayals of journals relative to their peers. In terms of citation-based influence, we found that the AFS journal Transactions of the American Fisheries Society (TAFS) and Fisheries magazine were competitive with highly regarded peer fisheries journals, but that North American Journal of Aquaculture (NAJA) and Journal of Aquatic Animal Health (JAAH) were less influential than their peers. The citation-based influence of North American Journal of Fisheries Management (NAJFM) was intermediate between TAFS/Fisheries and NAJA/JAAH . For journals like NAJFM and NAJA , we expect that much of the scientific influence on policy and management is not captured by citations in the primary literature, and alternative methods of evaluation may be needed. All of the AFS journals ranked highly with regard to cost-effectiveness because their subscription costs are low, and these rankings are in accordance with membership needs and the strategic mission of AFS to provide broad and timely dissemination of scientific information. We conclude by suggesting ways to increase the influence of AFS journals without compromising their accessibility and affordability, and offer advice about methods and frequency for future journal evaluations.

Fisheries↗
USGS2025

Integrating diverse stakeholder knowledge in recreational fisheries decision making

Scientists and policymakers increasingly recognize that recreational fisheries decision making should in some way involve the knowledge of affected stakeholders. There are myriad studies about integrating stakeholder knowledge, but they span broad disciplines and topics. Lacking is (i) simple taxonomies that organize general approaches for integrating knowledge, and (ii) a review and examples of their application to specifically recreational fisheries and specifically diverse stakeholders. This chapter first defines the terms “stakeholders” and “recreational” and recognizes that globally, the decision making for non-commercial fisheries often occurs outside of the North American concept of management agencies and even purely leisure-based fisheries. Most of the chapter reviews common approaches for integrating stakeholder knowledge, from near-complete external governance with minimal input from stakeholders (top-down, command-and-control) to self-governance by stakeholders. Organizationally, we adapt the existing cooperative management continuum to first separate non-participatory from participatory approaches and then separate participatory approaches into those aimed at creating knowledge (to eventually inform future decisions) and those focused on decision making itself. The approaches we consider include observing stakeholders (e.g., via survey), incorporating multiple types of knowing (e.g., local traditional knowledge), collaborative data collection (e.g., citizen science), collaborative modelling (e.g., mental models and quantitative modelling), participatory decision making (co-management proper and the special cases of structured decision making and adaptive management), and finally self-governance (including private management of recreational fisheries). We define each according to a broader literature beyond recreational fisheries, describe the recognized advantages and disadvantages, describe or summarize applications to recreational fisheries, and finally mention relevance for integrating specifically diverse stakeholder knowledge. We then provide advice for how to select different approaches, including situations in which certain approaches are more likely to produce intended consequences. We conclude by describing potential challenges to the more useful integration of diverse stakeholder knowledge and needs in recreational fisheries decision making.

Book chapter↗
USGS2019

Overlap of Pink-footed Shearwaters and central Chilean purse-seine fisheries: Implications for bycatch risk

Understanding susceptibility of seabirds to fisheries bycatch requires quantifying overlap of seabird at-sea habitat with fisheries’ distribution and effort. Pink-footed Shearwaters (Ardenna creatopus) are vulnerable seabirds that breed only in Chile. Recently, high rates of Pink-footed Shearwater bycatch (i.e. >1,500 observed mortalities 2015–2017) were documented by observers in central Chilean purse-seine fisheries. We present analysis of Pink-footed Shearwater at-sea movements and overlap with central Chilean purse-seine fleets targeting common sardine (Strangomera bentincki), Peruvian anchoveta (Engraulis ringens), and Chilean jack mackerel (Trachurus murphyi). To determine overlap during 2015–2017, we paired locations from 49 Pink-footed Shearwaters rearing nestlings at Isla Mocha, Chile, with locations and number of observed purse-seine sets in central Chile. Pink-footed Shearwaters typically visited waters ≤30 km offshore throughout central Chile. Foraging trip durations varied interannually, with longer trips in 2016, but all years revealed persistent foraging hotspots near Valdivia, the Gulf of Arauco, and Isla Mocha, Chile. Greatest overlap between Pink-footed Shearwaters and fisheries occurred with the sardine/anchoveta fleet near Valdivia (artisanal and industrial) and the Gulf of Arauco (artisanal); overlap with the jack mackerel fleet was minimal. Given Pink-footed Shearwater bycatch documented in these fisheries, this overlap may indicate risk of bycatch for these birds, although we did not directly quantify shearwater–fisheries interaction. Our results can inform further fishery monitoring efforts, as well as collaboration among scientists, managers, and fishers to identify, quantify, and reduce fisheries bycatch of Pink-footed Shearwaters within Chile and internationally.

The Condor↗
USGS2022

Biodiversity underpins fisheries resilience to exploitation in the Amazon River basin.

Inland fisheries feed greater than 150 million people globally, yet their status is rarely assessed due to their socio-ecological complexity and pervasive lack of data. Here, we leverage an unprecedented landings time series from the Amazon, Earth's largest river basin, together with theoretical food web models to examine (i) taxonomic and trait-based signatures of exploitation in inland fish landings and (ii) implications of changing biodiversity for fisheries resilience. In both landings time series and theory, we find that multi-species exploitation of diverse inland fisheries results in a hump-shaped landings evenness curve. Along this trajectory, abundant and large species are sequentially replaced with faster growing and smaller species. Further theoretical analysis indicates that harvests can be maintained for a period of time but that continued biodiversity depletion reduces the pool of compensating species and consequently diminishes fisheries resilience. Critically, higher fisheries biodiversity can delay fishery collapse. Although existing landings data provide an incomplete snapshot of long-term dynamics, our results suggest that multi-species exploitation is affecting freshwater biodiversity and eroding fisheries resilience in the Amazon. More broadly, we conclude that trends in landings evenness could characterize multi-species fisheries development and aid in assessing their sustainability.

Amazon River basin↗