Adaptation of sea turtles to climate warming: Will phenological responses be sufficient to counteract changes in reproductive output?

Sea turtles are vulnerable to climate change since their reproductive output is influenced by incubating temperatures, with warmer temperatures causing lower hatching success and increased feminization of embryos. Their ability to cope with projected increases in ambient temperatures will depend on their capacity to adapt to shifts in climatic regimes. Here, we assessed the extent to which phenological shifts could mitigate impacts from increases in ambient temperatures (from 1.5 to 3°C in air temperatures and from 1.4 to 2.3°C in sea surface temperatures by 2100 at our sites) on four species of sea turtles, under a “middle of the road” scenario (SSP2-4.5). Sand temperatures at sea turtle nesting sites are projected to increase from 0.58 to 4.17°C by 2100 and expected shifts in nesting of 26–43 days earlier will not be sufficient to maintain current incubation temperatures at 7 (29%) of our sites, hatching success rates at 10 (42%) of our sites, with current trends in hatchling sex ratio being able to be maintained at half of the sites. We also calculated the phenological shifts that would be required (both backward for an earlier shift in nesting and forward for a later shift) to keep up with present-day incubation temperatures, hatching success rates, and sex ratios. The required shifts backward in nesting for incubation temperatures ranged from −20 to −191 days, whereas the required shifts forward ranged from +54 to +180 days. However, for half of the sites, no matter the shift the median incubation temperature will always be warmer than the 75th percentile of current ranges. Given that phenological shifts will not be able to ameliorate predicted changes in temperature, hatching success and sex ratio at most sites, turtles may need to use other adaptive responses and/or there is the need to enhance sea turtle resilience to climate warming.18 página

Global Conservation Priorities for Marine Turtles

Where conservation resources are limited and conservation targets are diverse, robust yet flexible priority-setting frameworks are vital. Priority-setting is especially important for geographically widespread species with distinct populations subject to multiple threats that operate on different spatial and temporal scales. Marine turtles are widely distributed and exhibit intra-specific variations in population sizes and trends, as well as reproduction and morphology. However, current global extinction risk assessment frameworks do not assess conservation status of spatially and biologically distinct marine turtle Regional Management Units (RMUs), and thus do not capture variations in population trends, impacts of threats, or necessary conservation actions across individual populations. To address this issue, we developed a new assessment framework that allowed us to evaluate, compare and organize marine turtle RMUs according to status and threats criteria. Because conservation priorities can vary widely (i.e. from avoiding imminent extinction to maintaining long-term monitoring efforts) we developed a “conservation priorities portfolio” system using categories of paired risk and threats scores for all RMUs (n = 58). We performed these assessments and rankings globally, by species, by ocean basin, and by recognized geopolitical bodies to identify patterns in risk, threats, and data gaps at different scales. This process resulted in characterization of risk and threats to all marine turtle RMUs, including identification of the world's 11 most endangered marine turtle RMUs based on highest risk and threats scores. This system also highlighted important gaps in available information that is crucial for accurate conservation assessments. Overall, this priority-setting framework can provide guidance for research and conservation priorities at multiple relevant scales, and should serve as a model for conservation status assessments and priority-setting for widespread, long-lived taxa

Adaptation of sea turtles to climate warming: Will phenological responses be sufficient to counteract changes in reproductive output?

© 2023 The Authors. Global Change Biology published by John Wiley & Sons Ltd. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.Sea turtles are vulnerable to climate change since their reproductive output is influenced by incubating temperatures, with warmer temperatures causing lower hatching success and increased feminization of embryos. Their ability to cope with projected increases in ambient temperatures will depend on their capacity to adapt to shifts in climatic regimes. Here, we assessed the extent to which phenological shifts could mitigate impacts from increases in ambient temperatures (from 1.5 to 3°C in air temperatures and from 1.4 to 2.3°C in sea surface temperatures by 2100 at our sites) on four species of sea turtles, under a “middle of the road” scenario (SSP2-4.5). Sand temperatures at sea turtle nesting sites are projected to increase from 0.58 to 4.17°C by 2100 and expected shifts in nesting of 26–43 days earlier will not be sufficient to maintain current incubation temperatures at 7 (29%) of our sites, hatching success rates at 10 (42%) of our sites, with current trends in hatchling sex ratio being able to be maintained at half of the sites. We also calculated the phenological shifts that would be required (both backward for an earlier shift in nesting and forward for a later shift) to keep up with present-day incubation temperatures, hatching success rates, and sex ratios. The required shifts backward in nesting for incubation temperatures ranged from −20 to −191 days, whereas the required shifts forward ranged from +54 to +180 days. However, for half of the sites, no matter the shift the median incubation temperature will always be warmer than the 75th percentile of current ranges. Given that phenological shifts will not be able to ameliorate predicted changes in temperature, hatching success and sex ratio at most sites, turtles may need to use other adaptive responses and/or there is the need to enhance sea turtle resilience to climate warming.Peer reviewe

Adaptation of sea turtles to climate warming: Will phenological responses be sufficient to counteract changes in reproductive output?

Sea turtles are vulnerable to climate change since their reproductive output is influenced by incubating temperatures, with warmer temperatures causing lower hatching success and increased feminization of embryos. Their ability to cope with projected increases in ambient temperatures will depend on their capacity to adapt to shifts in climatic regimes. Here, we assessed the extent to which phenological shifts could mitigate impacts from increases in ambient temperatures (from 1.5 to 3°C in air temperatures and from 1.4 to 2.3°C in sea surface temperatures by 2100 at our sites) on four species of sea turtles, under a “middle of the road” scenario (SSP2‐4.5). Sand temperatures at sea turtle nesting sites are projected to increase from 0.58 to 4.17°C by 2100 and expected shifts in nesting of 26–43 days earlier will not be sufficient to maintain current incubation temperatures at 7 (29%) of our sites, hatching success rates at 10 (42%) of our sites, with current trends in hatchling sex ratio being able to be maintained at half of the sites. We also calculated the phenological shifts that would be required (both backward for an earlier shift in nesting and forward for a later shift) to keep up with present‐day incubation temperatures, hatching success rates, and sex ratios. The required shifts backward in nesting for incubation temperatures ranged from −20 to −191 days, whereas the required shifts forward ranged from +54 to +180 days. However, for half of the sites, no matter the shift the median incubation temperature will always be warmer than the 75th percentile of current ranges. Given that phenological shifts will not be able to ameliorate predicted changes in temperature, hatching success and sex ratio at most sites, turtles may need to use other adaptive responses and/or there is the need to enhance sea turtle resilience to climate warming

Adaptation of sea turtles to climate warming: Will phenological responses be sufficient to counteract changes in reproductive output?

Sea turtles are vulnerable to climate change since their reproductive output is influenced by incubating temperatures, with warmer temperatures causing lower hatching success and increased feminization of embryos. Their ability to cope with projected increases in ambient temperatures will depend on their capacity to adapt to shifts in climatic regimes. Here, we assessed the extent to which phenological shifts could mitigate impacts from increases in ambient temperatures (from 1.5 to 3°C in air temperatures and from 1.4 to 2.3°C in sea surface temperatures by 2100 at our sites) on four species of sea turtles, under a “middle of the road” scenario (SSP2-4.5). Sand temperatures at sea turtle nesting sites are projected to increase from 0.58 to 4.17°C by 2100 and expected shifts in nesting of 26–43 days earlier will not be sufficient to maintain current incubation temperatures at 7 (29%) of our sites, hatching success rates at 10 (42%) of our sites, with current trends in hatchling sex ratio being able to be maintained at half of the sites. We also calculated the phenological shifts that would be required (both backward for an earlier shift in nesting and forward for a later shift) to keep up with present-day incubation temperatures, hatching success rates, and sex ratios. The required shifts backward in nesting for incubation temperatures ranged from −20 to −191 days, whereas the required shifts forward ranged from +54 to +180 days. However, for half of the sites, no matter the shift the median incubation temperature will always be warmer than the 75th percentile of current ranges. Given that phenological shifts will not be able to ameliorate predicted changes in temperature, hatching success and sex ratio at most sites, turtles may need to use other adaptive responses and/or there is the need to enhance sea turtle resilience to climate warming. © 2023 The Authors. Global Change Biology published by John Wiley ; Sons Ltd.National Science Foundation, NSF: 1904818; U.S. Environmental Protection Agency, EPA: R82‐9094; United States Agency for International Development, USAID: IN201218, IN209520, IN210116, IN212119; U.S. Fish and Wildlife Service, USFWS; ADC Foundation; National Fish and Wildlife Foundation, NFWF; Disney Worldwide Conservation Fund, DWCF; Florida Atlantic University, FAU; Movistar Telefónica; National Save the Sea Turtle Foundation; Facultad de Química, Universidad Autonoma de Yucatan; Consejo Nacional de Ciencia y Tecnología, CONACYT: CVU 545214; Save Our Seas Foundation, SOSF; Comisión Nacional para el Conocimiento y Uso de la Biodiversidad, Gobierno de México, CONABIO; Comisión Nacional de Áreas Naturales Protegidas, CONANP; Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, ICML-UNAMThis work was supported from funding from the National Science Foundation (grant 1904818), the U.S. EPA STAR Program GAD (Grant R82‐9094), the American Geophysical Union‐Sharing Science Award, Disney Worldwide Conservation Fund, Save Our Seas Foundation, Nelligan Sea Turtle Fund, the National Save The Sea Turtle Foundation, the AWC Foundation, 4Ocean, Ashwanden Family Fund, the Department of Biological Sciences at Florida Atlantic University, QatarEnergy (QE), the National Fish and Wildlife Foundation, U.S. Fish and Wildlife Service, Wild Earth Allies, SEE Turtles, and U.S. Agency for International Development, UNAM PAPIIT/DGAPA (IN212119, IN209520, IN201218; IN210116). Monitoring activities at Celestún, Las Coloradas, El Cuyo, and Holbox were funded by US Fish and Wildlife Service, SAC‐TUN, Industria Salinera de Yucatán, S. A., Fondo Mexicano para la Conservación de la Naturaleza, Alianza World Wildlife Fund‐Fundación Carlos Slim, The Nature Conservancy, SEE Turtles Billion Baby Turtles Program, National Fish and Wildlife Foundation, Programa de Especies en Riesgo‐Comisión Nacional de Áreas Naturales Protegidas (CONANP), Programa de Monitoreo Biológico‐CONANP, Sea Turtle Inc., Coastal Wildlife Club, Fomento Social Banamex, Centro de Investigación y de Estudios Avanzados‐Mérida, Comisión Nacional para el Conocimiento y uso de la Biodiversidad, El Colegio de la Frontera Sur, Universidad Autónoma de Yucatán, KfW Development Bank, Instituto de Ciencias del Mar y Limnología‐UNAM, the Andrews Family, IdeaWild, Casa Tortuga, and Telefónica Movistar. The Boca Raton, Florida data would not have been available without the generous help of Gumbo Limbo Nature Center's Sea Turtle Specialists. Assistance with obtaining temperatures received essential help from K. Rusenko, D. Anderson, L. Celano, K. Esper, C. Gonzales, A. Lolavar, M. Rogers, B. Tezak, N. Warraich. S. Epperly, S. Heppell, and L. Crowder provided essential guidance in the earlier half of these data collections. Mariana Fuentes is thankful for all the personnel involved in collecting temperature data at Fernando de Noronha. Damla Beton, Annette Broderick, and Robin Snape thank the numerous supporters and volunteers of the Marine Turtle Conservation Project, in particular Roger de Freitas and the MAVA Foundation. M. J. Liles acknowledge the local egg collectors of Bahia de Jiquilisco and the dedicated members of Asociacion ProCosta for support with data collection, especially N. Sanchez, S. Chavarria, M. Valle, C. Pacheco, M. Pineda, A. Henriquez. Cynthia D. Flores‐Aguirre acknowledge the Posgrado en Ciencias Biológicas, UNAM, and CONACyT for the scholarship awarded to C. D. Flores‐Aguirre (CVU 545214); and for financial support. Oguz Turkozan and Can Yılmaz thank WWF‐Turkey for the financial support and the volunteers supporting the fieldwork. We also express our gratitude to all the personnel of the CONANP and PRO NATURA Península de Yucatán, AC. Also, to the Coordinación General del Servicio Meteorológico Nacional (CGSMN) de la Comisión Nacional del Agua (CONAGUA) for data related to environmental temperature and precipitation. Data gathering for “Las Cabras” Sinaloa, Mexico was financed by FONATUR and executed by ICML‐UNAM under permits SGPA/DGIRA/DG/1167/11 issued by DGIRA‐SEMARNAT. Data from Rio de Janeiro, Brazil, would not be possible without the efforts of the Marine Turtle Monitoring Program (PMTM), coordinated by Reserva Caruara and developed by Porto do Açu in partnership with Fundação Projeto Tamar and Ferroport, GNA and Vast. We are thankful for Alexa Putillo, who developed Figures 1–3 of this article and Scott Whiting for initial comments on drafts of the manuscript

Adaptation of sea turtles to climate warming: Will phenological responses be sufficient to counteract changes in reproductive output?

Sea turtles are vulnerable to climate change since their reproductive output is influenced by incubating temperatures, with warmer temperatures causing lower hatching success and increased feminization of embryos. Their ability to cope with projected increases in ambient temperatures will depend on their capacity to adapt to shifts in climatic regimes. Here, we assessed the extent to which phenological shifts could impacts from increases in ambient temperatures (from 1.5 to 3°C in air temperatures and from 1.4 to 2.3°C in sea surface temperatures by 2100 at our sites) on four species of sea turtles, under a “middle of the road” scenario (SSP2-4.5). Sand temperatures at sea turtle nesting sites are projected to increase from 0.58 to 4.17°C by 2100 and expected shifts in nesting of 26–43 days earlier will not be sufficient to maintain current incubation temperatures at 7 (29%) of our sites, hatching success rates at 10 (42%) of our sites, with current trends in hatchling sex ratio being able to be maintained at half of the sites. We also calculated the phenological shifts that would be required (both backward for an earlier shift in nesting and forward for a later shift) to keep up with present-day incubation temperatures, hatching success rates, and sex ratios. The required shifts backward in nesting for incubation temperatures ranged from −20 to −191 days, whereas the required shifts forward ranged from +54 to +180 days. However, for half of the sites, no matter the shift the median incubation temperature will always be warmer than the 75th percentile of current ranges. Given that phenological shifts will not be able to ameliorate predicted changes in temperature, hatching success and sex ratio at most sites, turtles may need to use other adaptive responses and/or there is the need to enhance sea turtle resilience to climate warming.info:eu-repo/semantics/publishedVersio