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Updated: Jul 10, 2026
13:18
Data Collection on Marine Litter Ingestion in Sea Turtles and Thresholds for Good Environmental Status
Published on: May 18, 2019
Small-scale fisheries bycatch jeopardizes endangered Pacific loggerhead turtles
S Hoyt Peckham1, David Maldonado Diaz, Andreas Walli
1Department of Ecology and Evolutionary Biology, University of California at Santa Cruz, Santa Cruz, California, United States of America. hoyt@biology.ucsc.edu
Plos One
|October 18, 2007
Summary
Small-scale fisheries pose a significant threat to endangered loggerhead turtles, with high bycatch rates in coastal areas. Local fishers are now working to eliminate bycatch and protect these vulnerable marine animals.
Area of Science:
- Marine Biology
- Fisheries Science
- Conservation Ecology
Background:
- Industrial fisheries bycatch impacts are well-documented, but small-scale fisheries impacts on migratory megafauna remain largely overlooked.
- Small-scale fisheries, employing most of the world's fishers, occur in coastal areas globally.
- Migratory megafauna, including sea turtles, frequent coastal habitats within small-scale fishing ranges, raising concerns about bycatch.
Purpose of the Study:
- To investigate the impact of small-scale fisheries on non-target megafauna, specifically loggerhead turtles.
- To quantify bycatch mortality in small-scale fisheries operating in high-use areas for juvenile loggerhead turtles.
Main Methods:
- Satellite tracking of 30 North Pacific loggerhead turtles to identify high-use areas.
- Partnering with local fishers to observe two small-scale fleets near a key loggerhead habitat.
- Conducting shoreline surveys to count discarded turtle carcasses.
Main Results:
- Juvenile loggerhead turtles spent 70% of their time in a high-use area overlapping with small-scale fisheries in Baja California Sur, Mexico.
- Minimum annual bycatch mortality from just two small-scale fleets exceeded 1000 loggerheads, rivaling industrial fisheries.
- This high bycatch rate threatens the persistence of the critically endangered North Pacific loggerhead turtle population.
Conclusions:
- Small-scale fisheries in coastal high-use areas represent a major threat to non-target megafauna globally.
- Urgent research is needed to quantify small-scale fisheries bycatch worldwide.
- Collaborative efforts with small-scale fishers are crucial for mitigating bycatch and ensuring megafauna survival.
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