skip to main content
US FlagAn official website of the United States government
dot gov icon
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
https lock icon
Secure .gov websites use HTTPS
A lock ( lock ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.


Title: Assessing impacts of bycatch policies and fishers’ heterogeneous information on food webs and fishery sustainability
Ecosystem-based fisheries management (EBFM) has emerged as a promising framework for understanding and managing the long-term interactions between fisheries and the larger marine ecosystems in which they are nested. However, successful implementation of EBFM has been elusive because we still lack a comprehensive understanding of the network of interacting species in marine ecosystems (the food web) and the dynamic relationship between the food web and the humans who harvest those ecosystems. Here, we advance such understanding by developing a network framework that integrates the complexity of food webs with the economic dynamics of different management policies. Specifically, we generate hundreds of different food web models with 20–30 species, each harvested by five different fishers extracting the biomass of a target and a bycatch species, subject to two different management scenarios and exhibiting different information in terms of avoiding bycatch when harvesting the target species. We assess the different ecological and economic consequences of these policy alternatives as species extinctions and profit from sustaining the fishery. We present the results of different policies relative to a benchmark open access scenario where there are no management policies in place. The framework of our network model would allow policymakers to evaluate different management approaches without compromising on the ecological complexities of a fishery. This article is part of the theme issue ‘Connected interactions: enriching food web research by spatial and social interactions’.  more » « less
Award ID(s):
2224915
PAR ID:
10556157
Author(s) / Creator(s):
; ;
Publisher / Repository:
The Royal Society
Date Published:
Journal Name:
Philosophical Transactions of the Royal Society B: Biological Sciences
Volume:
379
Issue:
1909
ISSN:
0962-8436
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. ABSTRACT We examine the coloniality of Alaska pollock (Walleye Pollock Gadus chalcogrammus) trawl fisheries governance and its role in enabling salmon bycatch, highlighting the resulting impacts on Alaska Native communities and subsistence practices. We expose how the systemic marginalization of Alaska Native voices and knowledge in federal fisheries management perpetuates dispossession, oppression, and is a barrier to food sovereignty and environmental justice. Alaska Native communities have long attributed the decline of salmon populations, particularly Chinook Salmon Oncorhynchus tshawytscha and Chum Salmon O. keta, to bycatch from the pollock trawl fishery—a concern ignored for over a decade. The repeated failure to meet salmon escapement goals has led to subsistence and commercial fishery closures, deepening food insecurity, health crises, and cultural disruption for Alaska Native peoples. Meanwhile, industrial trawl fisheries persist with minimal accountability, exacerbating ecological harm by capturing nontarget species, such as salmon, halibut, and crab, further impacting local, nonindustrial fisheries. We advocate for urgent reform of Alaska’s federal fisheries governance to center Alaska Native voices, integrate Indigenous knowledge, and address inequities in salmon allocation. Specifically, we call for revisions to the national standards of the Magnuson–Stevens Fishery Conservation and Management Act to ensure policies that respect Native sovereignty, promote sustainability, and mitigate the ecological and social consequences of industrial trawling. This approach is critical to achieving equitable and sustainable fisheries management that upholds environmental justice and Alaska Native rights. 
    more » « less
  2. Discards from commercial fisheries have been linked to detrimental effects on ecosystems and stocks of living marine resources. Understanding spatial and temporal patterns of discards may assist in devising regulatory practices and mitigation strategies and promote sustainable management policies. This study investigates data from bycatch monitoring programs using a machine learning approach. We used a gradient boosting classifier for describing catch and bycatch patterns in the U.S. Mid-Atlantic Black Seabass (Centropristis striata), Summer Flounder (Paralichthys dentatus), Scup (Stenotomus chrysops), and Longfin Squid (Doryteuthis pealeii) fisheries. We used oceanographic, biological, spatial, and fisheries data as explanatory model features. We found positive associations between target species volume and bycatch. Although we found that sea surface temperature and year were important model features, the direction of impact of those predictors was variable. From our findings, we conclude that machine learning approaches are promising in supplementing traditional methodologies, especially with the increase in data availability trends. 
    more » « less
  3. The emergence of ecosystem-based fisheries management (EBFM) has broadened the policy scope of fisheries management by accounting for the biological and ecological connectivity of fisheries. Less attention, however, has been given to the economic connectivity of fisheries. If fishers consider multiple fisheries when deciding where, when, and how much to fish, then management changes in one fishery can generate spillover impacts in other fisheries. Catch-share programs are a popular fisheries management framework that may be particularly prone to generating spillovers given that they typically change fishers’ incentives and their subsequent actions. We use data from Alaska fisheries to examine spillovers from each of the main catch-share programs in Alaska. We evaluate changes in participation—a traditional indicator in fisheries economics—in both the catch-share and non–catch-share fisheries. Using network analysis, we also investigate whether catch-share programs change the economic connectivity of fisheries, which can have implications for the socioeconomic resilience and robustness of the ecosystem, and empirically identify the set of fisheries impacted by each Alaska catch-share program. We find that cross-fishery participation spillovers and changes in economic connectivity coincide with some, but not all, catch-share programs. Our findings suggest that economic connectivity and the potential for cross-fishery spillovers deserve serious consideration, especially when designing and evaluating EBFM policies. 
    more » « less
  4. Abstract The management and conservation of tuna and other transboundary marine species have to date been limited by an incomplete understanding of the oceanographic, ecological and socioeconomic factors mediating fishery overlap and interactions, and how these factors vary across expansive, open ocean habitats. Despite advances in fisheries monitoring and biologging technology, few attempts have been made to conduct integrated ecological analyses at basin scales relevant to pelagic fisheries and the highly migratory species they target. Here, we use vessel tracking data, archival tags, observer records, and machine learning to examine inter‐ and intra‐annual variability in fisheries overlap (2013–2020) of five pelagic longline fishing fleets with North Pacific albacore tuna (Thunnus alalunga, Scombridae). Although progressive declines in catch and biomass have been observed over the past several decades, the North Pacific albacore is one of the only Pacific tuna stocks primarily targeted by pelagic longlines not currently listed as overfished or experiencing overfishing. We find that fishery overlap varies significantly across time and space as mediated by (1) differences in habitat preferences between juvenile and adult albacore; (2) variation of oceanographic features known to aggregate pelagic biomass; and (3) the different spatial niches targeted by shallow‐set and deep‐set longline fishing gear. These findings may have significant implications for stock assessment in this and other transboundary fishery systems, particularly the reliance on fishery‐dependent data to index abundance. Indeed, we argue that additional consideration of how overlap, catchability, and size selectivity parameters vary over time and space may be required to ensure the development of robust, equitable, and climate‐resilient harvest control rules. 
    more » « less
  5. Antonello, Alessandro (Ed.)
    Abstract The Pacific cod (Gadus macrocephalus) fishery was closed in 2020 after a rapid decline in biomass caused by the marine heat waves of 2014–2019. Pacific cod are exceptionally thermally sensitive and management of this fishery is now challenged by increasingly unpredictable climate conditions. Fisheries monitoring is critical for climate readiness, but short-term monitoring data may be inadequate for recognizing and anticipating change under rapid climate changes. We propose an interdisciplinary, marine historical ecology framework that looks to long-term records (local and traditional knowledge, history, archaeology, and paleoclimatology) to capture a long range of ecological variability and provide historical context for management. In order to connect to contemporary fisheries management, this framework must be built on a common vocabulary and an understanding of the key metrics used in fisheries stock assessments. Here, we propose metrics derived from Pacific cod stock assessment and synthesize information relevant to understanding the effects of past warming periods on cod populations across the Gulf of Alaska and Bering Sea. This case study provides a framework for thinking about how to use these historical records in the context of fisheries management under rapidly changing climate conditions. 
    more » « less