Sea Turtles and Survivability in Demersal Trawl Fisheries: Do Comatose Olive Ridley Sea Turtles Survive Post-Release?

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

Fulfilling global marine commitments; lessons learned from Gabon

As part of the Post-2020 Biodiversity Framework, nations are assessing progress over the past decade in addressing the underlying drivers that influence direct pressures on biodiversity and formulating new policies and strategies for the decade to come. For marine conservation, global marine protected area (MPA) coverage is still falling short of the 10% target set in 2010. Here we show that while this reflects a lack of progress in many low- and middle-income countries, a few of these nations have met or exceeded international commitments. To provide an in-depth explanation of how this was achieved in Gabon, we summarize the lessons learnt by our consortium of policy makers and practitioners who helped implement a comprehensive and ecologically representative network of 20 MPAs. We show the importance of creating a national framework, building long-term stakeholder support, and focusing on research that guides implementation and policy; and outline a four-step approach that countries and donors could use as an example to help meet international commitments. By responding to calls to share lessons learned to inform future Convention on Biological Diversity targets, we show how Gabon's experiences could inform change elsewhere.Output Status: Forthcoming/Available Online Additional co-authors: Tim Collins, Philip D. Doherty, Angela Formia, Mark Gately, Micheline Schummer Gnandji, Innocent Ikoubou, Judicael Régis Kema Kema, Koumba Kombila, Pavlick Etoughe Kongo, Jean Churley Manfoumbi, Sara M. Maxwell, Georges H. Mba Asseko, Catherine M. McClellan, Gianna Minton, Samyra Orianne Ndjimbou, Guylène Nkoane Ndoutoume, Jean Noel Bibang Bi Nguema, Teddy Nkizogho, Jacob Nzegoue, Carmen Karen Kouerey Oliwina, Franck Mbeme Otsagha, Diane Savarit, Stephen K. Pikesley, Philippe du Plessis, Hugo Rainey, Lucienne Ariane Diapoma Kingbell Rockombeny, Howard C. Rosenbaum, Dan Segan, Guy-Philippe Sounguet, Emma J. Stokes, Dominic Tilley, Raul Vilela, Wynand Viljoen, Sam B. Weber, Matthew J. Witt, Brendan J. Godle

Simulation of leatherback turtle hatchling dispersion patterns in the Gulf of Guinea

This data set describes the location of virtual floats representing turtle hatchlings throughout 60 modeled years. Floats were constrained to remain within depths of 0-6 m due to the positive buoyancy of hatchlings. Floats were first assigned to one of 20,000 random release locations within a large release area 125-400 km offshore from nesting beaches throughout the Republic/Democratic Republic of the Congo, Gabon and Equatorial Guinea spanning latitudes of c. 6°S to 3.5°N. For each month over the 4-month long hatching season (January-April), each of the 20,000 floats was assigned a random release day and drift simulations ran every year during the period 1960-2007 resulting in drift trajectories of approx. 4 million virtual floats. See Scott et al., 2017, Spatio-temporal variation in ocean current-driven hatchling dispersion: Implications for the world's largest leatherback sea turtle nesting region. Diversity Distrib, http://dx.doi.org/10.1111%2Fddi.12554 for details as to the model parameters. Each data set consists of data on the float ID (number 1,2,3 etc..) and its trajectory attributes (latitude/longitude) at each time step. Data are also provided on the temperature, salinity and density of the float at its respective position/time step. Data sets are sorted by float release date, and contain one data file for each year. Each data file has 11 columns, which contain the following data: float id, longitude, latitude, depth, time step, temperature, salinity, density, no time steps since start, distance to start point, bearing from start poin

Fulfilling global marine commitments; lessons learned from Gabon

As part of the Post-2020 Biodiversity Framework, nations are assessing progress over the past decade in addressing the underlying drivers that influence direct pressures on biodiversity and formulating new policies and strategies for the decade to come. For marine conservation, global marine protected area (MPA) coverage is still falling short of the 10% target set in 2010. Here we show that while this reflects a lack of progress in many low- and middle-income countries, a few of these nations have met or exceeded international commitments. To provide an in-depth explanation of how this was achieved in Gabon, we summarize the lessons learnt by our consortium of policy makers and practitioners who helped implement a comprehensive and ecologically representative network of 20 MPAs. We show the importance of creating a national framework, building long-term stakeholder support, and focusing on research that guides implementation and policy; and outline a four-step approach that countries and donors could use as an example to help meet international commitments. By responding to calls to share lessons learned to inform future Convention on Biological Diversity targets, we show how Gabon's experiences could inform change elsewhere