Unintended Victims: A Systematic Review of Global Marine Turtle By-Catch in Fisheries
Abstract
1. Introduction
2. Materials and Methods
2.1. Eligibility Criteria
2.2. Information Sources and Search Strategy
2.3. Study Selection and Data Extraction
2.4. Risk of Bias Assessment
2.5. Data Organization and Processing
2.6. Statistical Analyses and Synthesis of Results
3. Results and Discussion
3.1. Temporal Dynamics of Studies on Bycatch
3.2. Temporal Patterns in Sea Turtle Bycatch
3.3. Proportion of Bycatch by Sea Turtle Species
3.4. Relationship Between Methodology and Species Bycatch
3.5. Relationship Between Fishery Types, Gear Used, and Species Caught
3.6. Post-Capture Outcomes over Time
4. Conclusions
Supplementary Materials
Author Contributions
Funding
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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| Method | Description |
|---|---|
| Direct observation | Conducted in capture areas or along turtle migration and feeding routes, involving direct observation of interactions between turtles and fishing activities. |
| Interview | Conducted with local fishers to gather various information, such as the frequency of turtle bycatch, gear used, capture locations, and the fate of captured turtles. |
| Aerial monitoring | Use of aircraft, drones, or satellites, especially in remote or hard-to-access areas, such as nesting beaches or isolated fishing zones. |
| Mixed | Combination of multiple research methodologies, such as direct observation, interviews with fishers, and aerial monitoring. |
| Category | Included Subcategories |
|---|---|
| Net-based fishing | Trawl nets (e.g., bottom trawl and pelagic trawl), gillnets, set nets, fixed nets, purse seine nets, and drift nets |
| Hook-and-line fishing | Longlines and handlines (manual hook-and-line fishing) |
| Trap- and surround-based fishing | Submerged traps and dredges |
| Category | Included Subcategories |
|---|---|
| Human use | Commercialization, consumption, use in handicrafts, and religious practices |
| Discard | Disposal at sea after death |
| Research | Sent for necropsy, rehabilitation, research centers, and NGOs |
| Released | Live release after capture |
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© 2026 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license.
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da Silva, B.C.; Martins, L.G.; de Sousa, J.H.; de Oliveira, Y.C.B.B.; Nóbrega Alves, R.R. Unintended Victims: A Systematic Review of Global Marine Turtle By-Catch in Fisheries. Coasts 2026, 6, 2. https://doi.org/10.3390/coasts6010002
da Silva BC, Martins LG, de Sousa JH, de Oliveira YCBB, Nóbrega Alves RR. Unintended Victims: A Systematic Review of Global Marine Turtle By-Catch in Fisheries. Coasts. 2026; 6(1):2. https://doi.org/10.3390/coasts6010002
Chicago/Turabian Styleda Silva, Breno Carvalho, Lucas Garcia Martins, João Hemerson de Sousa, Yedda Christina Bezerra Barbosa de Oliveira, and Rômulo Romeu Nóbrega Alves. 2026. "Unintended Victims: A Systematic Review of Global Marine Turtle By-Catch in Fisheries" Coasts 6, no. 1: 2. https://doi.org/10.3390/coasts6010002
APA Styleda Silva, B. C., Martins, L. G., de Sousa, J. H., de Oliveira, Y. C. B. B., & Nóbrega Alves, R. R. (2026). Unintended Victims: A Systematic Review of Global Marine Turtle By-Catch in Fisheries. Coasts, 6(1), 2. https://doi.org/10.3390/coasts6010002

