- Overfishing of rockfish populations off the west coast of the US since the 1960s drastically reduced stocks.
- Rockfish Conservation Areas (RCAs) were established in 2002 with regulations like catch limits, gear restrictions, and seasonal closures to protect habitat and restrict catch.
- Outreach programs educate fishermen on RCA rules and provide devices to return bycatch to reduce mortality. Regulations have proven moderately successful at reducing bycatch and deterring prohibited catches.
This research article describes efforts to balance fisheries management goals of conserving overfished species while allowing fishing of abundant stocks. Large-scale fishery closures implemented in the late 1990s successfully reduced overfishing on the U.S. West Coast, but also constrained fishing and reduced data collection. The study developed and tested video survey and experimental fishing techniques to determine if abundant groundfish species could be caught in rocky habitats with minimal bycatch of rebuilding species still under restrictions. Comparing video surveys to fishing catches indicated modified fishing gear could target abundant stocks while limiting impacts on protected species, improving data collection as populations recover.
WGC 2016 poster on RCA EFP fishing surveysSteve Rienecke
This study aimed to develop methods for commercial fishermen to target healthy rockfish stocks while minimizing catches of rebuilding species. Researchers used existing data and local knowledge to identify areas and tested fishing gear that achieved catch ratios of over 10 pounds of target species for every 1 pound of rebuilding species. Visual surveys confirmed the presence of rebuilding species where none were caught, indicating the gear was selectively catching target species. The methods showed potential for fishermen to profitably target rebuilt populations while protecting depleted species.
This document summarizes evidence of "fishing down" coastal food webs in the Gulf of California over the past 30 years. Fisheries have shifted from catching large, long-lived predatory fish like sharks and groupers to smaller, short-lived species lower on the food chain. The maximum size of fish in catches has decreased 45 cm in just 20 years. While some total catches have increased, catch-per-unit-effort has declined for most species groups after 1980 due to a dramatic increase in fishing effort, particularly gillnets. This intensive fishing has not only impacted target species populations but also caused community-wide changes in fish assemblages. Coastal fisheries in the Gulf of California appear unsustainable
This study examined differences between lionfish captured on the Atlantic versus Caribbean sides of Vieques, Puerto Rico. The researchers measured lionfish weight, length, sex, and stomach contents. They found no statistically significant differences between lionfish on the two sides in terms of weight, length, sex ratio, or diet. This suggests lionfish are similarly successful in the different marine habitats along each coast of Vieques.
This document discusses management of the California swordfish fishery. It finds that utilizing multiple gear types, including drift gillnet, harpoon, and longline, would achieve the highest swordfish catch and profit without exceeding bycatch limits. This approach could reduce reliance on swordfish imports, which have higher bycatch rates, while decreasing global bycatch interactions. The analysis also considered reinstating a longline ban and increasing harpoon or inactive drift gillnet permits. Overall, the study aims to balance swordfish supply with bycatch reduction on both domestic and global scales.
The document summarizes research being conducted on barred sand bass by the Fisheries Independent/Scuba Assessment Project. The project is studying barred sand bass spawning movements and habitat use through acoustic tagging of fish and analysis of historical tagging data. They are also characterizing barred sand bass spawning habitat and seeking to determine spawning frequency by examining ovaries for evidence of recent spawning. The goal is to improve understanding of barred sand bass biology and behavior to better inform management of this important recreational fishery.
The document summarizes restoration projects undertaken in response to the 2007 Cosco Busan oil spill in San Francisco Bay. An estimated 6,849 birds of 65 species were killed by the spill. Partners led projects to enhance prey availability for wintering surf scoters, one of the most impacted species. Studies estimated mortality for each species and the number of injuries to inform scaling restoration actions to benefit injured populations.
2000PhD dissertation Options for Co-management of an Indonesian Coastal FisheryLida Pet
- Landings in Spermonde Archipelago, Indonesia increased from 32,000 tons in 1977 to 53,000 tons in 1995 while fishing effort only slightly increased. However, standard effort measures are unreliable due to increasing motorization.
- Perceptions of fisheries authorities and fishers on fishery status seem to concur but they cannot find evidence linking catch and effort due to constraints and lack of variation in Spermonde.
- Co-management is not viable yet and data needs to be standardized and combined on ecological rather than administrative grounds to better inform management.
This research article describes efforts to balance fisheries management goals of conserving overfished species while allowing fishing of abundant stocks. Large-scale fishery closures implemented in the late 1990s successfully reduced overfishing on the U.S. West Coast, but also constrained fishing and reduced data collection. The study developed and tested video survey and experimental fishing techniques to determine if abundant groundfish species could be caught in rocky habitats with minimal bycatch of rebuilding species still under restrictions. Comparing video surveys to fishing catches indicated modified fishing gear could target abundant stocks while limiting impacts on protected species, improving data collection as populations recover.
WGC 2016 poster on RCA EFP fishing surveysSteve Rienecke
This study aimed to develop methods for commercial fishermen to target healthy rockfish stocks while minimizing catches of rebuilding species. Researchers used existing data and local knowledge to identify areas and tested fishing gear that achieved catch ratios of over 10 pounds of target species for every 1 pound of rebuilding species. Visual surveys confirmed the presence of rebuilding species where none were caught, indicating the gear was selectively catching target species. The methods showed potential for fishermen to profitably target rebuilt populations while protecting depleted species.
This document summarizes evidence of "fishing down" coastal food webs in the Gulf of California over the past 30 years. Fisheries have shifted from catching large, long-lived predatory fish like sharks and groupers to smaller, short-lived species lower on the food chain. The maximum size of fish in catches has decreased 45 cm in just 20 years. While some total catches have increased, catch-per-unit-effort has declined for most species groups after 1980 due to a dramatic increase in fishing effort, particularly gillnets. This intensive fishing has not only impacted target species populations but also caused community-wide changes in fish assemblages. Coastal fisheries in the Gulf of California appear unsustainable
This study examined differences between lionfish captured on the Atlantic versus Caribbean sides of Vieques, Puerto Rico. The researchers measured lionfish weight, length, sex, and stomach contents. They found no statistically significant differences between lionfish on the two sides in terms of weight, length, sex ratio, or diet. This suggests lionfish are similarly successful in the different marine habitats along each coast of Vieques.
This document discusses management of the California swordfish fishery. It finds that utilizing multiple gear types, including drift gillnet, harpoon, and longline, would achieve the highest swordfish catch and profit without exceeding bycatch limits. This approach could reduce reliance on swordfish imports, which have higher bycatch rates, while decreasing global bycatch interactions. The analysis also considered reinstating a longline ban and increasing harpoon or inactive drift gillnet permits. Overall, the study aims to balance swordfish supply with bycatch reduction on both domestic and global scales.
The document summarizes research being conducted on barred sand bass by the Fisheries Independent/Scuba Assessment Project. The project is studying barred sand bass spawning movements and habitat use through acoustic tagging of fish and analysis of historical tagging data. They are also characterizing barred sand bass spawning habitat and seeking to determine spawning frequency by examining ovaries for evidence of recent spawning. The goal is to improve understanding of barred sand bass biology and behavior to better inform management of this important recreational fishery.
The document summarizes restoration projects undertaken in response to the 2007 Cosco Busan oil spill in San Francisco Bay. An estimated 6,849 birds of 65 species were killed by the spill. Partners led projects to enhance prey availability for wintering surf scoters, one of the most impacted species. Studies estimated mortality for each species and the number of injuries to inform scaling restoration actions to benefit injured populations.
2000PhD dissertation Options for Co-management of an Indonesian Coastal FisheryLida Pet
- Landings in Spermonde Archipelago, Indonesia increased from 32,000 tons in 1977 to 53,000 tons in 1995 while fishing effort only slightly increased. However, standard effort measures are unreliable due to increasing motorization.
- Perceptions of fisheries authorities and fishers on fishery status seem to concur but they cannot find evidence linking catch and effort due to constraints and lack of variation in Spermonde.
- Co-management is not viable yet and data needs to be standardized and combined on ecological rather than administrative grounds to better inform management.
Evidence for impacts by jellyfish on north searatupura
This study examines the potential impact of jellyfish on North Sea herring recruitment. It analyzes data on jellyfish and herring larval abundance in the North Sea from 1971-1986, excluding 1984. The study finds a positive correlation between jellyfish and herring larval abundance, indicating concurrence that could lead to competition. It also finds a negative relationship between survival of herring to age 0 and abundance of the jellyfish Aurelia aurita, suggesting this species may adversely impact herring populations. Finally, the study suggests climate variability, as measured by the North Atlantic Oscillation Index, may influence the impact of jellyfish on herring survival and recruitment through effects on jellyfish abundance.
Lavides et al 2016_reef fish disappearances Philippines_Plos One.PDFMargarita Lavides
This document summarizes a research article that uses fishers' knowledge to infer patterns of disappearance of coral reef finfish species in five marine biodiversity areas in the Philippines. Through interviews with over 2,600 fishers, the study identified 59 finfish species that have disappeared from catches between the 1950s and 2014. Five species that were reported to have zero catches by the most fishers were analyzed in more detail. Statistical models estimated an 88% decline in the catch of green bumphead parrotfish, an 82% decline in humphead wrasse, a 66% decline in African pompano, a 74% decline in giant grouper, and a 64% decline in mangrove red snapper based on
This study examined patterns of extirpation of ten grouper species in five marine areas in the Philippines based on interviews with 1,245 fishers and underwater surveys from 1950-2014. Fishers reported substantial declines in catch per unit effort (CPUE) for all ten species, ranging from 14.5-66.7% for normal days and 17.7-63.1% for good days. Underwater surveys found four of the ten species with very low sightings. Historical data also showed declines in grouper populations and catches since the 1980s. The results provide evidence that overfishing and habitat degradation have likely made grouper species vulnerable to depletion and possible local extinction if not properly managed.
The document discusses the depletion of fish biodiversity along the Indian coast due to overexploitation and environmental changes. It notes that over 70% of the world's fish species are fully exploited or depleted due to poor fisheries management, destructive fishing practices, and excessive bycatch. A study in Kerala found that two popular fish species, Lactarius lactarius and Pampus argenteus, have been depleted. Conservation measures like enforcing bycatch reduction technologies and regulating total fishing efforts are needed to protect marine biodiversity.
This document discusses issues facing the West Coast rock lobster fishing industry in South Africa. It notes that rock lobster populations have declined dramatically to only 3% of original levels due to overfishing. While the fishery has been carefully managed, a recent dispute emerged when government disregarded scientific advice and maintained catch limits, damaging conservation efforts. Additionally, rock lobsters are shifting locations and growing more slowly due to climate change and overfishing. Conservation groups are working to raise awareness of sustainable seafood choices.
Common dab (Limanda limanda) fisheries biology in the Northumberland coast (N...Paschalis Papadamakis
A possible MLS restriction was proposed for common dab (Limanda limanda) by determining age at length, and estimating growth parameters and length at first maturity. Individuals were collected in the Northumberland coastal waters, within the Northumberland Inshore Fisheries and Conservation Authority (NIFCA) area of jurisdiction (<6 nm offshore) by using three different fishing gears including demersal otter trawl, beam trawl and trammel nets. Otoliths were extracted for age determination and growth was described by applying the standard form of the von Bertalanffy growth equation to the mean lengths at age.
The document summarizes operations and research activities at KMRS in October. First, it describes the pearl seeding process where mature oysters are brought into the hatchery and seeded with nuclei by technicians. Seeded oysters are then mounted on panels and returned to sea lines. The document also introduces the latest interns, Hayley and Maddi, and describes their experiences. Finally, it provides details on two research collaborations in October studying juvenile fish recruitment and coral communities, and another in November examining soft sediment habitats, seagrass productivity, and grazing.
This report summarizes a 7-year study of the nearshore fish fauna in Bonne Bay, Newfoundland from 2002-2008. 31 fish species from 17 families were documented. Both juvenile and adult Atlantic cod were present, suggesting a local "bay cod" population. Acadian redfish and striped wolfish, a species protected under Canadian law, also inhabit the bay. Fish assemblages varied between different benthic habitats. The study provides a baseline for conservation efforts in the nationally protected bay, which supports diverse fish communities and species.
This document provides an overview and synthesis of the status and trends of Caribbean coral reefs from 1970 to 2012. It analyzes data on the biological abundance of corals, macroalgae, parrotfish and Diadema antillarum from over 40 reef sites across the Caribbean. The data shows long-term declines in coral cover and increases in macroalgal cover over this period. It also examines the main anthropogenic drivers of reef degradation, including overfishing, coastal pollution, climate change and the impacts of hurricanes. Finally, it provides recommendations to help guide management efforts to conserve these valuable ecosystems.
This study analyzed historical tag and recapture data from over 8,600 barred sand bass tagged in southern California between the 1960s and 1990s to understand their spawning-related movements. The data suggest barred sand bass reside at spawning grounds like Huntington Beach Flats for approximately one month during peak spawning season. While most non-spawning season recaptures occurred within 1 km of spawning locations, migrant fish averaged 13 km in movement away from spawning sites after spawning. The study also found evidence of site fidelity, as barred sand bass tended to return to the same spawning locations in subsequent years.
1. This document analyzes differences in physiological characteristics like condition factor and smolt index between landlocked Atlantic salmon reared at two Vermont hatcheries (ENFH and EWFCS) and wild salmon in the Huntington River.
2. Fish were sampled from the hatcheries and river over multiple months in 2011-2012. ENFH fish had a lower average condition factor than EWFCS fish. Both hatcheries' fish had higher condition factors than wild fish, though ENFH fish more closely resembled wild ones.
3. Rearing practices that minimize physiological differences between hatchery and wild salmon will increase stocked fish survival and support salmon population recovery in Vermont waters.
The 2020 annual report from the Treaty Indian Tribes in Western Washington summarizes tribal natural resource management activities over the past year, including:
1) Salmon harvest was reduced due to low returns, while shellfish and marine fish harvest was managed through cooperative agreements.
2) Habitat, hatchery, wildlife, and forest management programs were ongoing, while concerns remained regarding implementation of the culvert case ruling and potential rollbacks to water quality standards.
3) Regional collaboration on issues like orca recovery, salmon habitat protection, and pinniped management continued through groups like the Billy Frank Jr. Salmon Coalition.
The summary provides an overview of the Sea Duck Joint Venture newsletter. It discusses:
1) The newsletter shares news about the SDJV program and its work supporting research, surveys, and citizen science on sea duck populations.
2) The SDJV was created in 1999 to study declining sea duck populations and promote research and monitoring. It focuses on 5 species of highest concern.
3) The newsletter includes stories from partners on recent work counting eider duck migrations in Alaska and capturing and tagging sea ducks in Cape Cod Bay.
The document analyzes the impacts of drift gillnet fishing off the California coast. It finds that the fishery produces high rates of bycatch, catching over 17,000 marine animals from 2005-2015 while only keeping around 11,000. Though the size of the fishery and rates of bycatch have decreased in recent years, 30% bycatch is still considered high. Data from National Observer Program reports show the fishery catches many species of concern, including endangered whales, sea turtles, sharks and dolphins. While regulations have aimed to reduce impacts, conflicts remain due to the fishery's threats to biodiversity and protected species.
This document summarizes a study on the fisheries of the Keta Lagoon in Ghana. The Keta Lagoon supports important artisanal fisheries. Experimental fishing was conducted at three sites from 2010-2012 to study species composition, catch per unit effort, fishing methods, and fish sizes. A total of 21 fish species were recorded, with Tilapia guineensis, Sarotherodon melanotheron, Ethmalosa fimbriata, and Callinectes amnicola being most abundant. Length-weight relationships showed isometric growth for the dominant species. Species diversity was highest at Woe and lowest at Anyanui. Mean lengths and condition factors were estimated for the main species
- The study examined the distribution and identification of tuna larvae in the Phoenix Islands Protected Area from July to August 2014 through 49 sampling stations and 80 net samples.
- Tuna larvae accounted for only 4% of total larval fish collected but represented 3 of the 4 main commercial tuna species. Yellowfin tuna larvae were the most common.
- Larvae were concentrated near seamounts and islands and in the mixed layer above 100m. Meter nets in the mixed layer were the most effective sampling method.
- The data suggests the tuna fishery in the PIPA may be overfished given the low tuna larvae counts retrieved.
Seasonal Variations in Some Biological Parameters (Length-Weight Relationship...Premier Publishers
This study examined the seasonal variations in biological parameters of two commercially important pomfret species, silver pomfret (Pampus argenteus) and black pomfret (Parastromateus niger), caught from the Bay of Bengal. Length-weight relationships showed a negative allometric growth pattern in both sexes. Condition factor varied throughout the year but differences between months were not significant. Relative condition factor was highest in rainy and summer seasons for silver and black pomfret, respectively. Gonadosomatic index was highest in May for silver pomfret and March for black pomfret, indicating peak spawning periods. Hepatosomatic index values also increased during these periods. A secondary gonadosomatic
This study analyzed the stomach contents and stable isotope ratios of over 960 juvenile fish and their potential food sources from pelagic and littoral habitats in the tidal freshwater region of the San Francisco Estuary. The results showed evidence of two predominant food web pathways. Pelagic fish and some littoral fish relied on a zooplankton-phytoplankton trophic pathway, while the majority of littoral fish had diets and carbon isotope ratios consistent with energy from submerged aquatic vegetation and epiphytic macroalgae. Analysis with a mixing model revealed that littoral fish obtained the overall majority of their nutrition from consuming grazer amphipods. Examining both stable isot
This document discusses sustainable development of fisheries. It defines sustainable development as meeting present needs without compromising future generations' ability to meet their own needs. The FAO defines sustainable fisheries as managing natural resources and technological changes to ensure satisfying human needs now and in the future. Objectives include food security, profitable industries, long-term viability of resources, and ecosystem health. Unsustainable fisheries result from overcapacity, destructive practices, pollution and more. Solutions involve awareness, integration with coastal management, controlling land and access, stronger institutions, stakeholder participation, information sharing, socioeconomic understanding, enforcement, adapting to change, and community commitment.
The document provides information on the history, economic value, stock status, environmental impacts, stakeholders, and current management of the American lobster fishery. It discusses how lobsters were once used as fertilizer but became a culinary prize, the development of trap fishing, and the history of management from the 1940s onward. Stock status varies by region, with Gulf of Maine and Georges Bank stocks increasing but Southern New England critically depleted. The fishery generates hundreds of millions annually for New England. Current management divides the fishery into areas and stocks and regulates effort and catch through limits. Recommendations focus on improving conditions for the Southern New England stock and considering ecosystem and spatial issues.
This document examines factors affecting fish entrainment at the massive water diversions of the State Water Project and Central Valley Project in the San Francisco Bay Delta estuary. It analyzes 13 years of data on fish salvage counts, pumping operations, and environmental characteristics to determine what factors influence entrainment of different fish species. Entrainment of migratory pelagic species like delta smelt, longfin smelt, and striped bass was found to correlate with their seasonal occurrence near the export facilities. Flow patterns through the estuary also predicted pelagic fish entrainment. Entrainment of resident demersal species and littoral species was not clearly linked to diversion flows. The study suggests manipulating hydrodynamics
Evidence for impacts by jellyfish on north searatupura
This study examines the potential impact of jellyfish on North Sea herring recruitment. It analyzes data on jellyfish and herring larval abundance in the North Sea from 1971-1986, excluding 1984. The study finds a positive correlation between jellyfish and herring larval abundance, indicating concurrence that could lead to competition. It also finds a negative relationship between survival of herring to age 0 and abundance of the jellyfish Aurelia aurita, suggesting this species may adversely impact herring populations. Finally, the study suggests climate variability, as measured by the North Atlantic Oscillation Index, may influence the impact of jellyfish on herring survival and recruitment through effects on jellyfish abundance.
Lavides et al 2016_reef fish disappearances Philippines_Plos One.PDFMargarita Lavides
This document summarizes a research article that uses fishers' knowledge to infer patterns of disappearance of coral reef finfish species in five marine biodiversity areas in the Philippines. Through interviews with over 2,600 fishers, the study identified 59 finfish species that have disappeared from catches between the 1950s and 2014. Five species that were reported to have zero catches by the most fishers were analyzed in more detail. Statistical models estimated an 88% decline in the catch of green bumphead parrotfish, an 82% decline in humphead wrasse, a 66% decline in African pompano, a 74% decline in giant grouper, and a 64% decline in mangrove red snapper based on
This study examined patterns of extirpation of ten grouper species in five marine areas in the Philippines based on interviews with 1,245 fishers and underwater surveys from 1950-2014. Fishers reported substantial declines in catch per unit effort (CPUE) for all ten species, ranging from 14.5-66.7% for normal days and 17.7-63.1% for good days. Underwater surveys found four of the ten species with very low sightings. Historical data also showed declines in grouper populations and catches since the 1980s. The results provide evidence that overfishing and habitat degradation have likely made grouper species vulnerable to depletion and possible local extinction if not properly managed.
The document discusses the depletion of fish biodiversity along the Indian coast due to overexploitation and environmental changes. It notes that over 70% of the world's fish species are fully exploited or depleted due to poor fisheries management, destructive fishing practices, and excessive bycatch. A study in Kerala found that two popular fish species, Lactarius lactarius and Pampus argenteus, have been depleted. Conservation measures like enforcing bycatch reduction technologies and regulating total fishing efforts are needed to protect marine biodiversity.
This document discusses issues facing the West Coast rock lobster fishing industry in South Africa. It notes that rock lobster populations have declined dramatically to only 3% of original levels due to overfishing. While the fishery has been carefully managed, a recent dispute emerged when government disregarded scientific advice and maintained catch limits, damaging conservation efforts. Additionally, rock lobsters are shifting locations and growing more slowly due to climate change and overfishing. Conservation groups are working to raise awareness of sustainable seafood choices.
Common dab (Limanda limanda) fisheries biology in the Northumberland coast (N...Paschalis Papadamakis
A possible MLS restriction was proposed for common dab (Limanda limanda) by determining age at length, and estimating growth parameters and length at first maturity. Individuals were collected in the Northumberland coastal waters, within the Northumberland Inshore Fisheries and Conservation Authority (NIFCA) area of jurisdiction (<6 nm offshore) by using three different fishing gears including demersal otter trawl, beam trawl and trammel nets. Otoliths were extracted for age determination and growth was described by applying the standard form of the von Bertalanffy growth equation to the mean lengths at age.
The document summarizes operations and research activities at KMRS in October. First, it describes the pearl seeding process where mature oysters are brought into the hatchery and seeded with nuclei by technicians. Seeded oysters are then mounted on panels and returned to sea lines. The document also introduces the latest interns, Hayley and Maddi, and describes their experiences. Finally, it provides details on two research collaborations in October studying juvenile fish recruitment and coral communities, and another in November examining soft sediment habitats, seagrass productivity, and grazing.
This report summarizes a 7-year study of the nearshore fish fauna in Bonne Bay, Newfoundland from 2002-2008. 31 fish species from 17 families were documented. Both juvenile and adult Atlantic cod were present, suggesting a local "bay cod" population. Acadian redfish and striped wolfish, a species protected under Canadian law, also inhabit the bay. Fish assemblages varied between different benthic habitats. The study provides a baseline for conservation efforts in the nationally protected bay, which supports diverse fish communities and species.
This document provides an overview and synthesis of the status and trends of Caribbean coral reefs from 1970 to 2012. It analyzes data on the biological abundance of corals, macroalgae, parrotfish and Diadema antillarum from over 40 reef sites across the Caribbean. The data shows long-term declines in coral cover and increases in macroalgal cover over this period. It also examines the main anthropogenic drivers of reef degradation, including overfishing, coastal pollution, climate change and the impacts of hurricanes. Finally, it provides recommendations to help guide management efforts to conserve these valuable ecosystems.
This study analyzed historical tag and recapture data from over 8,600 barred sand bass tagged in southern California between the 1960s and 1990s to understand their spawning-related movements. The data suggest barred sand bass reside at spawning grounds like Huntington Beach Flats for approximately one month during peak spawning season. While most non-spawning season recaptures occurred within 1 km of spawning locations, migrant fish averaged 13 km in movement away from spawning sites after spawning. The study also found evidence of site fidelity, as barred sand bass tended to return to the same spawning locations in subsequent years.
1. This document analyzes differences in physiological characteristics like condition factor and smolt index between landlocked Atlantic salmon reared at two Vermont hatcheries (ENFH and EWFCS) and wild salmon in the Huntington River.
2. Fish were sampled from the hatcheries and river over multiple months in 2011-2012. ENFH fish had a lower average condition factor than EWFCS fish. Both hatcheries' fish had higher condition factors than wild fish, though ENFH fish more closely resembled wild ones.
3. Rearing practices that minimize physiological differences between hatchery and wild salmon will increase stocked fish survival and support salmon population recovery in Vermont waters.
The 2020 annual report from the Treaty Indian Tribes in Western Washington summarizes tribal natural resource management activities over the past year, including:
1) Salmon harvest was reduced due to low returns, while shellfish and marine fish harvest was managed through cooperative agreements.
2) Habitat, hatchery, wildlife, and forest management programs were ongoing, while concerns remained regarding implementation of the culvert case ruling and potential rollbacks to water quality standards.
3) Regional collaboration on issues like orca recovery, salmon habitat protection, and pinniped management continued through groups like the Billy Frank Jr. Salmon Coalition.
The summary provides an overview of the Sea Duck Joint Venture newsletter. It discusses:
1) The newsletter shares news about the SDJV program and its work supporting research, surveys, and citizen science on sea duck populations.
2) The SDJV was created in 1999 to study declining sea duck populations and promote research and monitoring. It focuses on 5 species of highest concern.
3) The newsletter includes stories from partners on recent work counting eider duck migrations in Alaska and capturing and tagging sea ducks in Cape Cod Bay.
The document analyzes the impacts of drift gillnet fishing off the California coast. It finds that the fishery produces high rates of bycatch, catching over 17,000 marine animals from 2005-2015 while only keeping around 11,000. Though the size of the fishery and rates of bycatch have decreased in recent years, 30% bycatch is still considered high. Data from National Observer Program reports show the fishery catches many species of concern, including endangered whales, sea turtles, sharks and dolphins. While regulations have aimed to reduce impacts, conflicts remain due to the fishery's threats to biodiversity and protected species.
This document summarizes a study on the fisheries of the Keta Lagoon in Ghana. The Keta Lagoon supports important artisanal fisheries. Experimental fishing was conducted at three sites from 2010-2012 to study species composition, catch per unit effort, fishing methods, and fish sizes. A total of 21 fish species were recorded, with Tilapia guineensis, Sarotherodon melanotheron, Ethmalosa fimbriata, and Callinectes amnicola being most abundant. Length-weight relationships showed isometric growth for the dominant species. Species diversity was highest at Woe and lowest at Anyanui. Mean lengths and condition factors were estimated for the main species
- The study examined the distribution and identification of tuna larvae in the Phoenix Islands Protected Area from July to August 2014 through 49 sampling stations and 80 net samples.
- Tuna larvae accounted for only 4% of total larval fish collected but represented 3 of the 4 main commercial tuna species. Yellowfin tuna larvae were the most common.
- Larvae were concentrated near seamounts and islands and in the mixed layer above 100m. Meter nets in the mixed layer were the most effective sampling method.
- The data suggests the tuna fishery in the PIPA may be overfished given the low tuna larvae counts retrieved.
Seasonal Variations in Some Biological Parameters (Length-Weight Relationship...Premier Publishers
This study examined the seasonal variations in biological parameters of two commercially important pomfret species, silver pomfret (Pampus argenteus) and black pomfret (Parastromateus niger), caught from the Bay of Bengal. Length-weight relationships showed a negative allometric growth pattern in both sexes. Condition factor varied throughout the year but differences between months were not significant. Relative condition factor was highest in rainy and summer seasons for silver and black pomfret, respectively. Gonadosomatic index was highest in May for silver pomfret and March for black pomfret, indicating peak spawning periods. Hepatosomatic index values also increased during these periods. A secondary gonadosomatic
This study analyzed the stomach contents and stable isotope ratios of over 960 juvenile fish and their potential food sources from pelagic and littoral habitats in the tidal freshwater region of the San Francisco Estuary. The results showed evidence of two predominant food web pathways. Pelagic fish and some littoral fish relied on a zooplankton-phytoplankton trophic pathway, while the majority of littoral fish had diets and carbon isotope ratios consistent with energy from submerged aquatic vegetation and epiphytic macroalgae. Analysis with a mixing model revealed that littoral fish obtained the overall majority of their nutrition from consuming grazer amphipods. Examining both stable isot
This document discusses sustainable development of fisheries. It defines sustainable development as meeting present needs without compromising future generations' ability to meet their own needs. The FAO defines sustainable fisheries as managing natural resources and technological changes to ensure satisfying human needs now and in the future. Objectives include food security, profitable industries, long-term viability of resources, and ecosystem health. Unsustainable fisheries result from overcapacity, destructive practices, pollution and more. Solutions involve awareness, integration with coastal management, controlling land and access, stronger institutions, stakeholder participation, information sharing, socioeconomic understanding, enforcement, adapting to change, and community commitment.
The document provides information on the history, economic value, stock status, environmental impacts, stakeholders, and current management of the American lobster fishery. It discusses how lobsters were once used as fertilizer but became a culinary prize, the development of trap fishing, and the history of management from the 1940s onward. Stock status varies by region, with Gulf of Maine and Georges Bank stocks increasing but Southern New England critically depleted. The fishery generates hundreds of millions annually for New England. Current management divides the fishery into areas and stocks and regulates effort and catch through limits. Recommendations focus on improving conditions for the Southern New England stock and considering ecosystem and spatial issues.
This document examines factors affecting fish entrainment at the massive water diversions of the State Water Project and Central Valley Project in the San Francisco Bay Delta estuary. It analyzes 13 years of data on fish salvage counts, pumping operations, and environmental characteristics to determine what factors influence entrainment of different fish species. Entrainment of migratory pelagic species like delta smelt, longfin smelt, and striped bass was found to correlate with their seasonal occurrence near the export facilities. Flow patterns through the estuary also predicted pelagic fish entrainment. Entrainment of resident demersal species and littoral species was not clearly linked to diversion flows. The study suggests manipulating hydrodynamics
(E5) Exercise #5: Gone Fishing
Goals
analyze annual fish landing, mortality, and biomass data;
explain what caused the collapse of groundfish populations in New
England;
define the terms overfishing and overfished;
understand how MPAs can be effective management tools for
preventing and reviving overfished populations;
and examine your role as a consumer in aiding the sustainability of fish
in our oceans.
Background
For as long as people have lived near water, people have fished. Sadly,
in many instances, the history of fishing is paralleled by a history of
overfishing. According to the 2006 Report of Status of U.S. Fisheries,
20% of U.S. fish stocks with known overfishing status are subject to
overfishing and 25% of stocks with known overfished status are
considered to be overfished. An additional four stocks currently
classified as not overfished are approaching overfished status.
Contributing factors to the current level of overfishing include:
technological advances that have made large-scale fishing easier;
too many fishing boats on the water;
international partnerships that allow foreign fleets to overfish in the waters of developing countries;
illegal fishing that violates fishing laws or agreements;
large amounts of bycatch of juvenile fish and non-target species; and
the shortcomings of fisheries conservation and management efforts.
The impacts of declining fish catches are being painfully felt by many coastal fishing communities around the globe.
Jobs are lost and food is scarce. Impacts are also felt in the oceans as other marine species are left with fewer fish to
eat. Overfishing affects the entire marine food web. But how do know when overfishing is occurring or when a
stock is overfished? More importantly, can these conditions be reversed?
Part 1: Overfishing in Georges Bank
Georges Bank is an underwater bank situated along the eastern edge of the Gulf of Maine between Cape Cod and
Nova Scotia. This region is one of the most biologically productive marine areas on the eastern seaboard,
historically accounting for a large percentage of New England's commercial fish landings. The Georges Bank fishery
is particularly well-known for its groundfish—species such as cod, haddock, and flounder that feed near the
bottom of the ocean.
Look at the graph on the next page of trends in Georges Bank haddock catch and mortality from 1969 through
2004.
The histogram shows the annual haddock landing—the amount of fish that are caught and kept to sell.
The red line shows the fishing mortality rate, F—the rate at which fish are removed from a population due
to fishing (as opposed to removals due to natural causes such as disease or predation). F can also be
thought of as the percentage of a population that die in one year due to fishing.
Map of the Gulf of Maine; Georges Bank is the light blue
region in the bottom center of the image. Image courtesy
of NOAA ...
NOAA scientists Jeffrey Polovina and Phoebe Woodworth-Jefcoats paper, "Fisher-Induced Changes in the Subtropical Pacific Pelagic Ecosystem Size Structure: Observations and Theory," was published in April 2013.
This National Wildlife Federation report details how 14 Gulf wildlife species are faring in the wake of BP's 2010 Deepwater Horizon oil disaster in the Gulf. Since the tragedy, NWF has closely monitored the harm done to wildlife and important habitats in the Gulf and along the coast. Though the full impacts of the oil spill remain unknown, this summarizes what we know so far, and what restoration still needs to be done. http://www.nwf.org/fouryearslater
This document summarizes a study that examined fish assemblages in reference and restored tidal freshwater marshes in the San Francisco Estuary. The study compared fish assemblages between one reference marsh and three restored marshes between 1998-1999. Fish were sampled using beach seines and purse seines in different habitats, including open water, submerged aquatic vegetation, offshore areas, tidal sloughs, and marsh edges. Overall, fish assemblages were dominated by introduced species and did not differ significantly between reference and restored marshes. However, fish assemblages did vary between habitats with and without submerged aquatic vegetation, and between offshore and nearshore habitats, with native fishes found more often in tidal sloughs
This document summarizes a study on the rockfish resources of the south central California coast. Researchers from California Polytechnic State University placed observers on party boats from 2003-2005 to record catch data by species, including catch per unit effort and mean size. They supplemented this with historical catch data from 1980-1998 from the California Department of Fish and Game and Pacific Gas & Electric. The study aims to analyze population trends over the past 25 years for various rockfish species in the region and compare sizes over time. Preliminary results found fluctuating catch rates but no consistent declining trends, except for bocaccio rockfish. Mean sizes were generally above maturity levels.
1. This document describes a study that developed a protocol using underwater videography to quantify trout populations. Video recordings were taken and analyzed from multiple cameras suspended in pools in Pauma Creek, part of the San Luis Rey River system in Southern California. This provided more accurate population data than other survey methods and was less detrimental to the imperiled fish populations.
2. The goal was to establish a lightweight camera system that could be easily deployed in remote areas to survey trout populations in less than an hour, as an alternative to electrofishing, netting, or snorkel surveys which can stress or harm the fish. The study focused on quantifying the native trout population in Pauma Creek, which historically contained coastal steelhead
This annual report from the Northwest Indian Fisheries Commission summarizes their work in 2021 managing natural resources in Western Washington through co-management with the state. It discusses declining salmon returns leading to reduced fishing opportunities, as well as efforts to protect and restore riparian habitat. It also covers impacts of seal and sea lion predation on salmon, COVID-19 impacts on tribal fisheries and economies, and the 50th anniversary of the "Fish Wars" that led to upholding treaty fishing rights in the Boldt decision.
Environmental impact of fishing and carbon footprinting due to fishingJEEVAN GOWDA
The document discusses the environmental impacts of fishing, including overfishing, bycatch, and effects on marine habitats. It provides details on how different fishing techniques can damage habitats and remove large amounts of seabed life. Bycatch is a major issue, with nets capturing mammals, sea turtles, sharks, and seabirds. The carbon footprint of fishing is also examined, with global fisheries estimated to emit 134 million tons of CO2 annually. The document concludes by stating that individuals and corporations can help mitigate climate change by reducing their carbon footprints through actions like purchasing carbon offsets.
“Coral reefs represent some of the world's most spectacular beauty spots, but they are also the foundation of marine life: without them many of the seas most exquisite species will not survive”
~ Sheherazade Goldsmith
“Coral is a very beautiful and unusual animal. Each coral head consists of thousand individual polyps. These polyps are continually budding and branching into genetically identical neighbors”
~ Antony Garrett Lisi
“The ocean stirs the heart, inspires the imagination and brings etrnal joy to the soul”
~ Wyland
The National Observer Program was established in 1990 to document bycatch in fisheries. The research will analyze reports from 2005-2015 to assess the impact of a fishery on marine wildlife. The fishery produces comparable amounts of bycatch and catch each year, though bycatch has declined. Despite regulations, the fishery remains unsustainable and harms marine ecosystems through drift gillnets. The use of drift gillnets should be phased out and replaced with more selective gear, while incentivizing sustainable methods through policy changes. Marine protected areas should also be expanded to conserve wildlife and habitats.
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Concise Summary
Increased fishing pressure on rockfish populations off the west coast of the United States
has drastically reduced rockfish fishery stocks since the 1960s. Rockfish Conservation Areas
were established in 2002 to restrict rockfish catch and protect rockfish habitat by implementing
seasons, catch limits, prohibited species retention lists, fishing depth limits, and gear restrictions.
NOAA Fisheries and the California Department of Fish and Wildlife established dockside and
charter outreach programs to educate fishermen on RCA zone regulations and to provide
descending devices to anglers so that rockfish bycatch could be returned to depth. The
implementation of RCA zone regulations have proven to be moderately successful at reducing
rockfish bycatch and have deterred anglers from retaining prohibited species.
Stock assessments have provided valuable data towards developing effective
management strategies in RCA zones for overfished and healthy stocks. However, recent data
suggests that older and larger females contribute disproportionately more offspring to the
population as a function of body size and sexual maturity in comparison to smaller and younger
females. RCA regulations permit a maximum retention of 10 rockfish per day, and as a result
larger fish are typically selected by anglers (commercial and recreational) as the preferred catch
to retain. These fishing practices are inhibiting the recovery of overfished and vulnerable
rockfish populations. Stricter size restrictions for retainable catch need to be implemented in
RCA zones in order to protect the larger females that overwhelming contribute more offspring to
their populations.
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Introduction
In response to growing concerns over declining marine fishery stocks, conservation has
become a very powerful platform within the environmental movement in recent decades. As a
result of increased fishing pressure around the globe, certain coastal species such as rockfish
have become greatly overfished. In particular, the potential for the collapse of rockfish fisheries
off the U.S. west coast has increased awareness for the need of conservation efforts.
Increased dependence on ocean resources has imposed significantly larger fishing
pressure on rockfish fisheries that have never before been experienced as a result of human
activity. In order to ensure the sustainability of rockfish fisheries for future generations,
significant conservation efforts must continue to be made to restrict bycatch and over-harvesting.
Over the duration of this report, I will refer to stock assessment data and discuss effective
management strategies that have been implemented in the Rockfish Conservation Area (RCA)
along the west coast of the United States.
Background
Since the late 19th century, as a result of the high demand that rockfish carry, several
rockfish species off the California coast have become greatly overfished. According to the
California Department of Fish and Wildlife, “yelloweye, canary, cowcod, bocaccio, widow,
pacific ocean perch and darkblotched rockfish have been federally designated ‘overfished
species’, which means that less than 25 percent of their estimated pre-fishery population now
exists” (California Department of Fish and Wildlife, 2015). The target biomass for overfished
species to reach in order to no longer be designated overfished, is 40 percent of their estimated
pre-fishery population (California Department of Fish and Wildlife, 2015). To reach target
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biomass (40%), many rockfish species require anywhere from 3-11 years and occasionally 20-30
years to fully mature and reach maximum reproductive capacity (Beyer et al., 2015).
In response to declining rockfish populations along the west coast of the United States,
the Rockfish Conservation Area (RCA) displayed in figure 1 below, was enacted in September
of 2002, to restrict recreational and commercial fishing from identified rockfish habitat.
According to NOAA Fisheries, “The locations of the RCA boundaries are set primarily to
minimize incidental catch of overfished rockfish by eliminating fishing in areas where and times
when those overfished species are likely to co-occur with more healthy target stocks of
groundfish” (NOAA, 2015). Since the enactment of the Rockfish Conservation Area, the stock
assessments of several rockfish species indicate that they
have rebounded to near or above the 40 percent target
biomass (NOAA, 2015).
(Figure 1: Map of the RCA Boundary Along Central California Coast.
Source: Beyer, 2015)
Findings
The RCA established depth restrictions (varying between 37-
180 meters) all along the California, Oregon, and
Washington coastlines in order to prevent fishing at depths
that rockfish inhabit (Beyer et al., 2015). Within each
specified RCA zone, fishermen are only allowed to fish above a specified depth in order to
prevent rockfish bycatch. The RCA also established gear restrictions, catch limits, seasons, and
restricted species that are illegal to retain. Gear was restricted to one line per fishermen, with a
maximum of two hooks per line. Seasons begin as early as April 1 and end as late as December
31. Bag limits were set at 10 per day, with a maximum retention of five (5) black rockfish, three
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(3) bocaccio rockfish, and three (3) cabezon rockfish (NOAA, 2015). However, there are four
species in Monterey Bay that are specifically prohibited to retain, which are: the canary rockfish,
the yelloweye rockfish, the bronzespotted rockfish, and the cowcod rockfish (NOAA, 2015).
As part of conservation efforts, fishermen are not only encouraged to prevent catching
rockfish, but to also return them to depth using any one of several descending devices such as a
Shelton descending device. Often when rockfish are caught, even unintentionally, fishermen are
unaware that they can return the fish back to its appropriate depth in order to reverse the
barotrauma that it suffers from at the surface. Barotrauma can be defined as, the physical damage
to body tissue that occurs as a result of significant and rapid change in ambient pressure, which
again occurs when the fish is caught and brought from great depth to the surface.
When suffering from barotrauma, a rockfish’s swim-bladder fills with gas as it ascends
towards the surface, and the expanding swim-bladder displaces the internal organs, typically
forcing the stomach and esophagus to protrude out from the fish’s mouth. These fish appear to
look dead according to most fishermen, and they usually just throw them back into the ocean.
Unfortunately, the excess gas in their bodies due to low-pressure conditions makes descending
on their own very difficult, if not impossible because of their very high buoyancy. However,
studies by John Hyde and Nick Wegner at NOAA Fisheries Southwest Fisheries Science Center
show that if a rockfish is returned to its appropriate depth with the use of a descending device
within just a few minutes of reaching the surface, it has roughly a 92.7 percent survival rate
(Hyde & Wegner, 2014).
These studies were conducted off the coast of southern California, where fifty (50)
rockfish of five (5) different species were caught, tagged, and recompressed at depth. Hyde and
Wegner monitored fish movement using an accelerometer and a pressure sensitive acoustic tag to
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determine short-term and long-term survival after being re-submerged to depth using a
descending device. The data indicated that 92.7 percent survived up to 2 days and 76.7 percent
survived more than four months, which was the battery power lifespan of the tags (Hyde &
Wegner, 2014).
(Figure 2: Displays the Fecundity of four Rockfish species relative to Female Fork Length. Source: Beyer, 2015)
Illustrated in figure 2, recent rockfish fecundity
analysis conducted locally at the NOAA Fisheries
SWFSC this spring indicated that, older and larger
females experienced a disproportionately greater
reproductive output than smaller and younger females
(Beyer, 2015). Also, “greater maternal investment by
older and larger females may further promote larval
survival and contribute significantly to recruitment” (Beyer et al., 2015). Older and larger
females have also been found to release larvae earlier in the season, which lengthens the
reproductive season, providing the opportunity to release multiple broods (Beyer et al., 2015).
These were important finding for several reasons, but most importantly the implications of these
findings suggest that the retention of highly desired, older and larger fish that are primarily
selected by recreational and commercial fishermen, can severely inhibit population growth and
stock recovery. This is a major concern for conservationists since the stocks of several of these
species are currently designated overfished by the California Department of Fish and Wildlife.
Recommendations
While rockfish populations are on the rise, many more years lie ahead until rockfish
fishery stocks can safely be designated sustainable. So far, dockside and charter outreach efforts
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to both recreational and commercial fishermen have been moderately successful at introducing
descending devices and supplying regulation handbooks for fishermen to use and follow while at
sea. However, further outreach at California’s marinas is certainly needed in order to provide the
foundation for conservation efforts to be more successful. Future stock assessments will also
continue to serve as an essential component to adequately quantify the success of current and
future conservation efforts in Rockfish Conservation Areas. With further input from data
acquired in future stock assessments, I believe that significant gains can continue to be made
towards restoring rockfish populations to historical levels.
However, my greatest concern resides with the retention of older and larger females.
Though rockfish catch has been greatly reduced due to RCA zone regulations, outreach efforts
should be adjusted to address this area of concern. I believe that rockfish conservation efforts can
be enhanced substantially by just reducing the catch of these individuals that contribute
disproportionately more to the population. Stricter size restrictions should be implemented into
RCA regulations to prevent the loss of these fish that are essential to continued population
growth and fishery stock health.
Despite the concerns mentioned above, I can conclude that the overall efforts that have
been made since the enactment of the Rockfish Conservation Area has certainly been successful.
Dockside and charter outreach programs have certainly achieved their objectives in providing
fishermen with descending devices and educating them on rockfish conservation and the RCA
zone regulations. Stock assessments, monitoring programs, and fecundity analysis have also been
very successful at projecting population growth and providing the necessary data to calculate
catch limits and harvest restrictions. I am hopeful that future efforts will continue with further
success.
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Reference List
Beyer, Sabrina. G., Sogard, Susan. M., Harvey, Chris. J., Field, John. C. (2015). Variability in
rockfish (Sebastes spp.) fecundity: species contrasts, maternal size effects, and spatial
differences. Springer Science. Environ Biol Fish (2015) 98:81-100
Beyer, Sabrina (2015). Rockfish Early Life History Project and Fecundity Analysis. Intern
Summary Spring Quarter 2015. NOAA Fisheries Southwest Fisheries Science Center,
Fisheries Ecology Division.
California Department of Fish and Wildlife (2015). Yelloweye, Canary, and other Rockfish
Species of Concern. Marine Conservation. Retrieved from:
https://www.dfg.ca.gov/marine/groundfishcentral/yelloweye.asp
Hyde, John. Wegner, Nick (2014). Barotrauma. NOAA Fisheries Southwest Fisheries Science
Center. Retrieved From:
https://swfsc.noaa.gov/textblock.aspx?Division=FRD&id=17814
National Oceanic and Atmospheric Administration (2015). Rockfish Conservation Areas:
Management, Law & Policy. NOAA Fisheries Southwest Fisheries Science Center.
Retrieved From:
http://www.westcoast.fisheries.noaa.gov/fisheries/management/groundfish_closures/rock
fish_areas.html