The impact generated on Sea Turtles by Fisheries in the Southwestern Atlantic Ocean

This document, which is directed at the fishing sector, researchers, conservationists and fishery administrators, was developed by researchers who are members of the Specialists Group for Marine Turtle Research and conservation in the Southwestern Atlantic Ocean (SWA) in response to the urgent need to evaluate the impact generated on sea turtles by fisheries. Historically, sea turtle conservation efforts have focused almost exclusively on the protection of nesting beaches. Nevertheless, over the last decade, research has proved incidental mortality as a result of fishing activities to be one of the greatest threats to these animals. This type of interaction is not only problematic for turtles, but also generates financial losses for fishermen and businesses. In spite of the efforts that are currently underway, researchers still do not have a detailed understanding of the impact that bycatch produces on sea turtle populations in the SWA. We have a long way to go before its effects can be minimized. Further research is needed regarding the biology and ecology of the various turtle species as well as the effective application of mitigation measures. The life cycles of sea turtles are long and complex. Turtles occupy various ecosystems (nesting beaches, coastal, neritic and oceanic zones, as well as pelagic and demersal areas) throughout their lifetimes, transcending various Exclusive Economic Zones and International Waters. The five species that inhabit the SWA region perform vast feeding and reproductive migrations, traveling through areas where many different fishing fleets operate. Therefore, sea turtles in the SWA interact with virtually all fisheries. These circumstances make it necessary to carry out biological, fishing related and conservation studies on a regional level. The efficiency of the existing international and national legal instruments has yet to be determined, in terms of their effectiveness in protecting sea turtles. In some cases, legislation that is specifically related to the interaction between fisheries and turtles does exist, such as those laws requiring the mandatory use of turtle excluding devices (TEDs). There are also explicit bans on sea turtle capture. Nevertheless, none of these regulations prevent sea turtle bycatch. Although some regional legal instruments are needed, these and the existing legislation will only be effective if they are accompanied by a broader range of permanent education and control measures, to achieve the commitment of all the parties involved. The ecosystem approach is gaining popularity among fishery administration organizations. Research and conservation efforts should also be moving in that direction. A regional and international effort is required in order to compile information regarding the bycatch produced by the various types of fisheries and fleets operating in the area. The enormous increase in fishing pressure that these fleets are exerting in this area has not been accompanied by an increase in information regarding the bycatch of species that have no commercial value. Pelagic longlining is one of the fishing methods, which must be most closely monitored, due to the high levels of bycatch that it produces, as well its ample distribution throughout the region, and the high level of fishing effort that it accounts for. Coastal trawlers and gillnetters must also be considered critical players, because they too produce a large rate of bycatch. These are the three types of fisheries that are most broadly distributed throughout the region, accounting for the majority of the fishing effort. Most of the institutions that work toward sea turtle conservation in the area have only begun to address the issue of bycatch over the last decade. This timeframe is reflected in the scope and quantity of the available publications, as well as the progress of activities directed at mitigating this problem. All of the institutions that have been mentioned in this report have made the gathering of information regarding interaction between sea turtles and fisheries one of their top priorities. Some institutions are even developing working programs for monitoring fisheries and testing mitigation measures. Many of these institutions have managed to develop adequate relationships with fishermen, ship owners and administrators. Nevertheless, limited access to funding is an obstacle to the development and testing of mitigation measures. The SWA network, which is a very valuable instrument that was created in 2003, has allowed the region’s institutions and researchers to exchange information and share their experience, in addition to lending each other support in carrying out joint activities, thus strengthening sea turtle conservation efforts. The capacity demonstrated so far by the region’s researchers and institutions, testifies to their ability to continue to make progress in knowledge generation and tests of bycatch mitigation measures.

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