학술논문
Sea turtles and survivability in demersal trawl fisheries: Do comatose olive ridley sea turtles survive post-release?
Document Type
Academic Journal
Author
Maxwell, Sara M.; Witt, Matthew J.; Abitsi, Gaspard; Aboro, Marie Pierre; Agamboue, Pierre Didier; Asseko, Georges Mba; Boussamba, François; Chartrain, Emmanuel; Gnandji, Micheline Schummer; Mabert, Brice Didier Koumba; Makanga, Felicien Mavoungou; Manfoumbi, Jean Churley; Nguema, Jean Noel Bibang Bi; Nzegoue, Jacob; Oliwina, Carmen Karen Kouerey; Sounguet, Guy-Philippe; Formia, Angela
Source
Animal Biotelemetry. September 10, 2018, Vol. 6 Issue 1
Subject
Language
English
ISSN
2050-3385
Abstract
Author(s): Sara M. Maxwell[sup.1,10] , Matthew J. Witt[sup.2] , Gaspard Abitsi[sup.3] , Marie Pierre Aboro[sup.4] , Pierre Didier Agamboue[sup.3] , Georges Mba Asseko[sup.5] , François Boussamba[sup.4] , Emmanuel Chartrain[sup.4] , [...]
Incidental capture of air-breathing species in fishing gear is a major source of mortality for many threatened populations. Even when individuals are discarded alive, they may not survive due to direct injury, or due to more cryptic internal physiological injury such as decompression sickness. Post-release mortality, however, can be difficult to determine. In this pilot study, we deployed survivorship pop-up archival tags (sPAT) (n = 3) for an air-breathing species, the olive ridley sea turtle (Lepidochelys olivacea), one of the first studies to do so. We found that at least two of the three turtles survived after being captured in demersal fish trawl nets and being resuscitated from a comatose state following standard UN Food and Agriculture Organization guidelines. One turtle died; however, the absence of a change in light level but continued diving activity suggested that the turtle was likely predated. Whether capture contributed to the turtle's susceptibility to predation post-release is unknown, and average tow duration during this fishing trip was similar in duration to that of a turtle that survived (1.5 h). The two surviving turtles displayed normal horizontal and vertical movements based on previous tagging studies. This study suggests that resuscitation techniques may be effective; however, additional study is necessary to increase sample sizes, and to determine the severity of decompression sickness across different levels of activity and in other fishing gears. This will result in better population mortality estimates, as well as highlight techniques to increase post-release survivorship. Keywords: Post-release mortality, Trawl fishing, Bycatch, Resuscitation, Decompression sickness, Olive ridley sea turtle
Incidental capture of air-breathing species in fishing gear is a major source of mortality for many threatened populations. Even when individuals are discarded alive, they may not survive due to direct injury, or due to more cryptic internal physiological injury such as decompression sickness. Post-release mortality, however, can be difficult to determine. In this pilot study, we deployed survivorship pop-up archival tags (sPAT) (n = 3) for an air-breathing species, the olive ridley sea turtle (Lepidochelys olivacea), one of the first studies to do so. We found that at least two of the three turtles survived after being captured in demersal fish trawl nets and being resuscitated from a comatose state following standard UN Food and Agriculture Organization guidelines. One turtle died; however, the absence of a change in light level but continued diving activity suggested that the turtle was likely predated. Whether capture contributed to the turtle's susceptibility to predation post-release is unknown, and average tow duration during this fishing trip was similar in duration to that of a turtle that survived (1.5 h). The two surviving turtles displayed normal horizontal and vertical movements based on previous tagging studies. This study suggests that resuscitation techniques may be effective; however, additional study is necessary to increase sample sizes, and to determine the severity of decompression sickness across different levels of activity and in other fishing gears. This will result in better population mortality estimates, as well as highlight techniques to increase post-release survivorship. Keywords: Post-release mortality, Trawl fishing, Bycatch, Resuscitation, Decompression sickness, Olive ridley sea turtle