FLAME University, Pune, Maharashtra, India

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Anthropogenic climate change is one of the primary threats to the environment and human society (Pecl et al., 2017; Lenton et al., 2019). This planetary-level modification has had unprecedented effects on ecosystems and biodiversity (Newson et al., 2009; Walther, 2010). Numerous species have already demonstrated alterations in their distribution and phenology, amongst other responses (Walther, 2010; Feeley et al., 2017; Piao et al., 2019). For example, mobile species like tropical fish have responded to climate change by migrating to more habitable regions, usually poleward or to deeper water, in order to find their preferred range of oxygen availability or water temperature (Munday et al., 2008). Milder winters have caused a significant increase in brown plumage in populations of tawny owls, allowing them to blend in better with the surrounding forest, in Europe (Karell et al., 2011). Moreover, fruit flies in southern, high-latitude areas of Australia are demonstrating genetic mutations common to more northern populations of the country as the species has adapted to drier and hotter conditions. Scientists have attributed these changes to climate change and have observed similar trends in Europe and North America as well (Umina et al., 2005).

Sea turtles are another taxon likely to be affected by climate change, across all their life stages. The predicted impacts include:

  • Sex ratios: As sea turtles have temperature-dependent sex determination, increase in incubation temperatures at nesting beaches may result in the feminisation of some populations (e.g., Janzen, 1994; Santidrián Tomillo et al., 2015a; Jensen et al., 2018) and decreased egg fertilisation rates (Glen & Mrosovsky, 2004; Lalöe et al., 2014; Jensen et al., 2018; Phillott & Godfrey, 2020).
  • Embryo development: Embryo development is faster at higher temperatures, reducing the incubation period and allowing less time for embryo growth (Reid et al., 2009). The result is smaller hatchlings, with implications for predation rates and performance.
  • Hatching success: Even small increases at the upper range of incubation temperatures can negatively affect hatching success (the proportion of eggs that hatch to produce hatchlings; Miller, 1999). For example, an increase from 30°C to 31°C mean incubation temperature can decrease hatching success by up to 25% (Howard et al., 2014). Changes in average precipitation may also affect hatching success (Santidrián Tomillo et al., 2012; Rafferty et al., 2017; Montero et al., 2018), with heavy rainfall increasing hatching success at drier nesting sites and the opposite or variable effects occurring at high-precipitation sites. (Santidrián Tomillo et al., 2015b; Montero et al., 2019). Lower hatching success will have implications for population recruitment and resilience.
  • Hatchling survival and performance: As incubation temperatures increase above 32°C, hatchlings perform more poorly on tests to assess their crawling, self-righting, and swimming abilities. Decreased locomotor performance at sea will make hatchlings more vulnerable to predation (Booth, 2017, 2018).
  • Movements and distribution at sea: Being ectothermic, sea turtles are affected by seawater temperature (Milton & Lutz, 2003). For example, Kemp’s ridley (Lepidochelys kempii) turtles that disperse further north to forage with warmer sea surface temperatures (SSTs) during autumn months, then retreat too slowly from cold waters in winter, are at greater risk of cold-stunning (Griffin et al., 2019). Some populations are already adapting to changing ocean temperatures, such as Eastern Pacific olive ridley (Lepidochelys olivacea) turtles that forage more northwards during an El Niño year to avoid warm waters and seek more productive upwelling areas (Plotkin, 2010), and hawksbill (Eretmochelys imbricata) turtles in the Arabian/Persian Gulf that move out of shallow, coastal foraging areas during the summer months when aquatic temperatures exceed 33°C (Pilcher et al., 2014; Marshall et al., 2020).
  • Reproductive output: The size of adult hawksbill turtles in the Arabian/Persian Gulf and Red Sea may be restricted by relatively poor foraging habitat and/or success due to extreme thermal environments. A smaller body size will limit clutch size in nesting females (Chatting et al., 2018; Mobaraki et al., 2022). There are indications that the number of yolkless eggs, comprising only an eggshell and egg white or albumen, laid by hawksbill turtles in these extreme environments are greater than that in other populations worldwide; the statistical likelihood and biological implications of this have yet to be determined (Mobaraki et al., 2022).
  • Nesting habitat: Many current nesting beaches utilised by sea turtles will likely be reduced in area by sea level rise, with beaches in developed regions being the most vulnerable (Fish et al., 2005; Baker et al., 2006; Fuentes et al., 2010). Coastal development can prevent the natural movement of sediment to replenish beaches, causing coastal squeeze, thus, exacerbating the impacts of sea level rise (Fish et al., 2008; Mazaris et al., 2009a; Biddiscombe et al., 2020).
  • Geographic range: In response to climate change, sea turtles may shift their nesting (Mancino et al., 2022) and foraging (Patel et al., 2021) habitat. Range shift in the form of range expansion (as opposed to contraction), that exposes sea turtles to greater human activities, lesser quality habitat, and other threats, could form an ecological trap (Pike, 2013; Maffucci et al., 2016). Range shift could also be beneficial, although thoroughly validated examples have not yet been reported in the published literature. 
  • Emerging diseases and pathogens: Outbreaks of infectious diseases in some marine taxa have increased in the last few decades, likely driven by anthropogenic climate change (Fisher et al., 2012; Altizer et al., 2013; Sanderson & Alexander, 2020). In sea turtles, warmer waters could increase the rate of tumour growth in animals with fibropapillomatosis (Herbst, 1994, 1995; Foley et al., 2005) and the pathogenicity, transmission pathways, and host susceptibility in any disease (see Mashkour et al., 2020). The association of climate change with emerging diseases in the terrestrial environment, such as sea turtle egg fusariosis (Gleason et al., 2020), has not been conclusively determined. Loss of nesting area with climate change-driven sea level rise will likely increase nest density (Patricio et al., 2019) with implications for microbial load in sea turtle nests (Honarvar et al., 2016) and the spread of pathogens among adjacent clutches (Sarmiento-Ramirez et al., 2017). Foraging habitats, including seagrass meadows (Sullivan et al., 2018) and coral reefs (Precht et al., 2016; Tracy et al., 2019), may also be impacted by disease and/or pathogens.
  • Nesting phenology: Alterations in the timing of seasonal activities among animals and plants is a commonly observed ecological response to environmental perturbations like climate change (Walther et al., 2002). Oceans have absorbed ~80% of the heat added to the environment (IPCC, 2007), impacting parameters like sea surface temperature (Hoegh-Guldberg et al., 2007), biogeochemical composition (Harley et al., 2006), and sea level (Meehl et al., 2005). Ocean temperature affects the onset of nesting, duration of the nesting season, nest abundance, clutch size, mean nesting date, and other parameters of the nesting phenology of loggerhead (Caretta caretta) sea turtles in Florida (Lamont & Fujisaki, 2014). However, patterns are not always consistent. For example, higher annual SST adjacent to nesting beaches (Weishampel et al., 2004, 2010; Pike et al., 2006; Hawkes et al., 2007; Mazaris et al., 2008, 2013; Lamont & Fujisaki, 2014; Patel et al., 2016) and at foraging sites (Mazaris et al., 2009b, Monsinjon et al., 2019) have both been correlated with earlier nesting. Longer (Weishampel et al., 2010; Lamont & Fujisaki, 2014) and shorter nesting seasons (Pike, 2009; Weishampel et al., 2010), and reduced inter-nesting intervals (Weber et al., 2011; Valverde-Cantillo et al., 2019), have been recorded in warmer years. Higher SST at nesting locations has also been associated with fewer total clutches, primarily as a result of fewer turtles nesting (Mazaris et al., 2009b; Reina et al., 2009; Patel et al., 2016). Earlier nesting is predicted to mitigate exposure of eggs to lethal temperatures (Almpanidou et al., 2018) and strongly female-biased sex ratios (e.g., Abella Perez et al., 2016) that are predicted to occur with higher environmental temperatures due to climate change.

We note that the El Niño-Southern Oscillation (ENSO) and North Atlantic Oscillation are known or predicted to affect nesting in some sea turtle populations (e.g., Limpus & Nicholls, 1988; Chaloupka et al., 2008; Saba et al., 2008; Quiñones et al., 2010; Mortimer, 2012; Arendt et al., 2013; Bruno et al., 2020; Santidrián Tomillo et al., 2020; Hays et al., 2022) but not others (Ariano-Sánchez et al., 2020; Santidrián Tomillo et al., 2020; Hays et al., 2022). However, the impact of climate change on ENSO is still uncertain in the face of contradictory findings (e.g., Yang et al., 2018; Alizadeh, 2022; Geng et al., 2022); therefore, we do not include this in the above list.

The impacts of climate change on sea turtles, and its mitigation, were identified as a priority research area to inform conservation and management of sea turtles by Hamann et al. (2010). Subsequent reviews examined topics on which research has focused at a global scale, and found a growing body of knowledge, predominantly in the terrestrial phase of the sea turtle life cycle (Rees et al., 2016; Patricio et al., 2021). However, recent regional reviews found the impacts and/or mitigation of climate change on sea turtles were not well studied in the northwestern Indian Ocean and the east coast of Africa despite it being regarded by experts as an increasing threat (Al Ameri et al., 2022; van de Geer et al., 2022). 

While studies on all the potential impacts of climate change on sea turtles deserve attention, understanding how nesting phenology may be affected is important, as changes in timings of migration and the onset and duration of nesting have the potential to exacerbate or mitigate the impacts of climate change (Pike et al., 2006; Mazaris et al., 2008; Pike, 2009; Weishampel et al., 2010; Patel et al., 2016). For example, the timing of the nesting season has implications for the exposure to climatic conditions and hatching success (Santidrián Tomillo et al., 2012) and offshore currents facilitating hatchling dispersal and in-water survival (Shillinger et al., 2012; Le Gouvello et al., 2020). Hence, we conducted a systematic review of methods used worldwide in published studies examining alterations in sea turtle nesting phenology with climate change, e.g., changes in sea surface temperature, to identify the most common methods of collecting data and the variables examined. The findings of the review can inform and guide researchers in the Indian Ocean and Southeast Asia region (and beyond) who are interested in monitoring potential changes in nesting phenology at their study site/s.


Google Scholar was used as the search engine to identify empirical studies, based on primary data, on the research topic. We performed a literature search using the key words/phrases “sea” OR “marine” AND “turtle” AND “nesting phenology”. The search was restricted to literature published in peer reviewed journals and professional newsletters (e.g., Indian Ocean Turtle Newsletter, Marine Turtle Newsletter) to date in the 21st century (2000-2021). Results were screened through 1) review of title and abstract; then, 2) review of methods and results for relatedness to the research topic. The reference list of relevant literature was also examined to identify further studies pertinent to the topic that had not been identified through the search on Google Scholar.

After close reading of the texts, common themes and categories of data of interest were identified (emergent coding). Data about the focus species, geographic region, study objective, source and collection frequency of environmental data, metric/s of sea turtle nesting phenology, and finding/s were extracted from each paper and descriptive statistics used to summarise the proportion of studies within each code.


From a total of 407 search results, filtering identified 15 publications that met our criteria and were included in the systematic review: Weishampel et al. (2004, 2010), Pike et al. (2006), Hawkes et al. (2007), Mazaris et al. (2008, 2009b, 2013), Pike (2009), Hassine et al., (2011), Dalleau et al. (2012), Lamont & Fujisaka (2014), Neeman et al. (2015), Patel et al. (2016), Monsinjon et al. (2019), and Valverde-Cantillo et al. (2019). All examined changes in nesting phenology in association with SST.

Loggerhead (73.3%) and green (Chelonia mydas; 26.7%) turtles were the subject of all but one of the nesting phenology studies examined. No studies considered flatback (Natator depressus), hawksbill, Kemp’s ridley, or olive ridley turtles (Table 1). Most research was conducted in the northwest Atlantic (53.3%) and Mediterranean (33.3%) regions; this geographic bias led to the species bias, as loggerhead and green turtles predominantly nest in these regions. Only one study, in the southwest Indian Ocean (Dalleau et al., 2012), examined the impacts of climate change on nesting phenology in the Indian Ocean basin and no studies from Southeast Asia were found. The geographic and species bias indicates a knowledge gap in understanding the potential for climate change-driven changes in sea turtle nesting phenology in the Indian Ocean region, especially as sea turtles in the northwest Indian Ocean experience extreme nesting and foraging environments (e.g., Pilcher et al., 2014; Marshall et al., 2020; Chatting et al., 2021), key foraging grounds in Southeast Asia seas are threatened by marine heatwaves (Konsta et al., 2022), and other regional management units for species in the region are at risk from the threat of climate change or insufficient data is publicly available to predict the risk (Wallace et al., 2011). The knowledge gap can also be the result of challenges in collecting data, especially over a long time period, and the scarcity of baseline data for comparison.

Table 1. Sea turtle species and geographic region in studies (n=15) assessing the variation in nesting phenology with sea surface temperature. Totals exceed 100% as some studies examined more than one parameter.

Of the parameters of nesting ecology investigated, the most common were the start/onset and the length/duration of the nesting season (53.3% each), followed by the median day of the nesting season (46.7%; Table 2). Identifying the date on which the nesting season begins and ends, and calculating the median date, may require few resources and be potentially more accurate than ongoing monitoring of beaches throughout the nesting season to estimate peak nesting date, inter-nesting period, and start of hatchling emergence. Note that Patricio et al. (2021) suggests using the 2.5th percentile of the nesting date as a proxy for the commencement of nesting, to avoid any outlying data for populations with seasonal nesting. (The 2.5th percentile is the date before which 2.5% of nesting events occurred.) Researchers should also be aware that these metrics can be impractical for assessing shifts in nesting phenology in populations that have bimodal or year-round nesting (Dalleau et al., 2012). 

Table 2. Parameter of nesting ecology examined in studies (n=15) assessing variation in nesting phenology with sea surface temperature. Totals exceed 100% as some studies examined more than one parameter.

SST data used in the studies we examined was primarily derived from central data sources (80.0%) at monthly intervals (50.0%) (Table 3). For instance, Pike et al. (2006) sourced their SST data from an automated data logger attached to buoy 41009 of the National Data Buoy Center. Similarly, Weishampel et al. (2004) obtained SST values from a National Oceanic and Atmospheric Administration (NOAA) buoy (Station 41009). Using environmental data from a central source removes the need for researchers to purchase and place data loggers at individual study sites. Future research could utilise satellite-derived SST data (see O’Carroll et al., 2019; Momin et al., 2022).

Table 3. Source, interval, and location of sea surface temperature data in studies (n=15) assessing the variation in nesting phenology with sea surface temperature.

Examining SST data from waters adjacent to nesting beaches alone was the most common approach (60.0%) (Table 3), potentially since nesting beaches are known locations and foraging areas for individuals in a nesting population may be broadly distributed geographically. Only two studies (13.3%) used SSTs at both foraging areas and nesting beaches to understand variation in nesting phenology with SSTs at different habitats. Their findings were different, but complementary. Loggerhead turtles in Brazil started their migration in response to environmental cues at foraging areas, which determines the onset of the nesting season (Mosinjon et al., 2019), whilst loggerhead turtles in Greece nested earlier after an increase in SST at the nesting site (Patel et al., 2016).

The majority of studies assessed potential changes in nesting phenology at only one nesting location (73.3%; Table 4). Data sets across all studies ranged from 1-36 years in length; studies at single locations examined data from a Mean±StDev duration of 16.6±7.3yr (range 4-26yr). This area of research would potentially benefit from broad acceptance of the standards for appropriate baseline data and temporal scale of data needed to determine changes in nesting phenology with appropriate statistical power.

Table 4. Number of nesting sites in studies (n=15) assessing the variation in nesting phenology with sea surface temperature.

Finally, we emphasise that comparison of findings among studies can be challenging (Patricio et al., 2021). The onset of nesting may reflect atypical events (outliers) and the median nesting date can also be ambiguous given that it is affected both by the onset and duration of the nesting season (Mazaris et al., 2013) as well as survey effort (Patricio et al., 2021). Changes in sea turtle nesting phenology parameters in response to SST has also been found to vary with latitude (Mazaris et al., 2013).


Sea turtle populations in the Indian Ocean and southeast Asia are threatened by climate change, and some are data deficient on the potential impacts of this threat (see Phillott & Rees, 2021). We have summarised the methods used in worldwide studies that assessed changes in nesting phenology with climate change published from 2000-2021 to inform researchers interested in similar studies at their nesting and/or monitoring sites. Our summary does not imply that the same method(s) would be the most suitable for all locations, but the information we present can be used as a starting point for researchers new to the field of study. We also remind researchers to be cautious and not to assume climate change-induced changes in sea turtle nesting phenology, since reproductive ecology depends on many factors, including resource availability and acquisition, environmental cues at foraging and breeding sites, courtship, population demographics, and geography (Patricio et al., 2021).


We acknowledge the suggestions from the anonymous peer-reviewers, which were incorporated into the paper.

Literature cited:

Abella Perez, E., A. Marco, S. Martins & L.A. Hawkes. 2016. Is this what a climate change-resilient population or marine turtles looks like? Biological Conservation 193: 124-132.

Al Ameri, H.M., S. Al Harthi, A. Al Kiyumi, T.S. Al Sariri, A.S.Y. Al-Zaidan, M. Antonopoulou, A.C. Broderick, et al. 2022. Biology and conservation of marine turtles in the northwestern Indian Ocean: A review. Endangered Species Research 48: 67-86.

Alizadeh, O. 2022. Amplitude, duration, variability, and seasonal frequency analysis of the El Niño-Southern Oscillation. Climatic Change 174: 20. DOI: 10.1007/s10584-022-03440-w.

Almpanidou, V., E. Katragkou & A.D. Mazaris. 2018. The efficiency of phenological shifts as an adaptive response against climate change: A case study of loggerhead sea turtles (Caretta caretta) in the Mediterranean. Mitigation and Adaptation Strategies for Global Change 23: 1143-1158.

Altizer, S., R.S. Ostfeld, P.T. Johnson, S. Kutz & C.D. Harvell. 2013. Climate change and infectious diseases: From evidence to a predictive framework. Science 341: 514-519.

Arendt, M.D., J.A. Schwenter, B.E. Witherington, A.B. Meylan & V.S. Saba. 2013. Historical versus contemporary climate forcing on the annual nesting variability of loggerhead sea turtles in the northwest Atlantic Ocean. PLOS ONE 8: e81097. DOI: 10.1371/journal.pone.0081097.

Ariano-Sánchez, D., C. Muccio, F. Rosell & S. Reinhardt. 2020. Are trends in olive ridley sea turtle (Lepidochelys olivacea) nesting abundance affected by El Niño-Southern Oscillation (ENSO) variability? Sixteen years of monitoring on the Pacific coast of northern Central America. Global Change and Conservation 24: e01339. DOI: 10.1016/j.gecco.2020.e01339.

Baker, J.D., C.L. Littnan & D.W. Johnston. 2006. Potential effects of sea level rise on the terrestrial habitats of endangered and endemic megafauna in the northwestern Hawaiian Islands. Endangered Species Research 2: 21-30. 

Biddiscombe, S.J., E.A. Smith & L.A. Hawkes. 2020. A global analysis of anthropogenic development of marine turtle nesting beaches. Remote Sensing 12: 1492. DOI: 10.3390/rs12091492.

Booth, D.T. 2017. Influence of incubation temperature on sea turtle hatchling quality. Integrative Zoology 12: 352-360. 

Booth, D.T. 2018. Incubation temperature induced phenotypic plasticity in oviparous reptiles: Where to next? Journal of Experimental Zoology Part A: Ecological and Integrative Physiology 329: 343-350.

Bruno, R.S., J.A. Restrepo & R.A. Valverde. 2020. Effects of El Niño-Southern Oscillation and local ocean temperature on the reproductive output of green turtles (Chelonia mydas) nesting at Tortuguero, Costa Rica. Marine Biology 167: 128. DOI: 10.1007/s00227-020-03749-z.

Chaloupka, M., N. Kamezaki & C. Limpus. 2008. Is climate change affecting the population dynamics of the endangered Pacific loggerhead sea turtle? Journal of Experimental Biology and Ecology 356: 136-143.

Chatting, M., D. Smyth, I. Al-Maslamani, J. Obbard, M. Al-Ansi, S. Hazma, S.F. Al-Mohanady, et al. 2018. Nesting ecology of hawksbill turtles, Eretmochelys imbricata, in an extreme environment setting. PLOS ONE 13: e203257. DOI: 10.1371/journal.pone.0203257.

Chatting, M., S. Hamza, J. Al-Khayat, D. Smyth, S. Husrevoglu, & C.D. Marshall. 2021. Feminization of hawksbill turtle hatchlings in the twenty-first century at an important regional nesting aggregation. Endangered Species Research 44: 149-158.

Dalleau, M., S. Ciccione, J.A. Mortimer, J. Garnier, S. Benhamou & J. Bourjea. 2012. Nesting phenology of marine turtles: Insights from a regional comparative analysis on green turtles (Chelonia mydas). PLOS ONE 7: e46920. DOI: 10.1371/journal.pone.0046920.

Feeley, K.J., J.T. Stroud & T.M. Perez. 2017. Most ‘global’ reviews of species’ responses to climate change are not truly global. Diversity and Distributions 23: 231-234.

Fish, M.R., I.M. Côté, J.A. Gill, A.P. Jones, S. Renshoff & A.R. Watkinson. 2005. Predicting the impact of sea-level rise on Caribbean sea turtle nesting habitat. Conservation Biology 19: 482-491.

Fish, M.R., I.M. Côté, J.A. Horrocks, B. Mulligan, A.R. Watkinson & A.P. Jones. 2008. Construction setback regulations and sea-level rise: Mitigating sea turtle nesting beach loss. Ocean and Coastal Management 51: 330-341.

Fisher, M.C., D.A. Henk, C.J. Briggs, J.S. Brownstein, L.C. Madoff, S.L. McCraw & S.J. Gurr. 2012. Emerging fungal threats to animal, plant and ecosystem health. Nature 484: 186-194.

Foley, A.M., B.A. Schroeder, A.E. Redlow, K.J. Fick-Child & W.G. Teas. 2005. Fibropapillomatosis in stranded green turtles (Chelonia mydas) from the eastern United States (1980−98): Trends and associations with environmental factors. Journal of Wildlife Diseases 41: 29-41.

Fuentes, M.M.P.B.., C.J. Limpus, M. Hamann & J. Dawson. 2010. Potential impacts of projected sea-level rise on sea turtle rookeries. Aquatic Conservation: Marine and Freshwater Ecosystems 20: 132-139.

Geng, T., W. Cai, L. Wu, A. Santoso, G. Wang, Z. Jing, et al. 2022. Emergence of changing Central-Pacific and Eastern-Pacific El Niño-Southern Oscillation in a warming climate. Nature Communications 13:6616. DOI: 10.1038/s41467-022-33930-5.

Gleason, F.H., M. Allerstorfer & O. Lilje. 2020. Newly emerging diseases of marine turtles, especially sea turtle egg fusariosis (SEFT), caused by species in the Fusarium solani complex (FSSC). Mycology 11: 184-194.

Glen, F. & N. Mrosovsky. 2004. Antigua revisited: The impact of climate change on sand and nest temperatures at a hawksbill turtle (Eretmochelys imbricata) nesting beach. Global Change Biology 10: 2036-2045.

Griffin, L.P., C.R. Griffin, J.T. Finn, R.L. Prescott, M. Faherty, B.M. Still & A.J. Danylchuk. 2019. Warming seas increase cold-stunning events for Kemp’s ridley sea turtles in the northwest Atlantic. PLOS ONE 14: e0211503.

Hamann, M., M.H Godfrey, J.A. Seminoff, K. Arthur, P.C.R. Barata, K.A. Bjorndal, A.B. Bolten, et al. 2010. Global research priorities for sea turtles: Informing management and conservation in the 21st century. Endangered Species Research 11: 245-269.

Harley, C.D.G., A.R. Hughes, K.M. Hultgren, B.G. Miner, C.J.B. Sorte, C.S. Thornber, L.F. Rodriguez, et al. 2006. The impacts of climate change in coastal marine systems. Ecology Letters 9: 228-241.

Hassine, S.B., I. Jribi, M.N. Bradai, A. Bouain & M. Girondot. 2011. The origin in variability of nesting period of the loggerhead turtle (Caretta caretta) in the Kuriat Islands, Tunisia. Marine Turtle Newsletter 131: 48-50.

Hawkes, L.A., A.C. Broderick, M.H. Godfrey & B.J. Godley. 2007. Investigating the potential impacts of climate change on a marine turtle population. Global Change Biology 13: 923-932.

Hays, G.C., A.D. Mazaris and G. Schofield. 2022. Inter-annual variability in breeding census data across species and regions. Marine Biology 169: 54. DOI: 10.1007/s00227-022-04042-x.

Herbst, L.H. 1994. Fibropapillomatosis of marine turtles. Annual Review of Fish Diseases 4: 389-425. 

Herbst, L.H., E.R. Jacobson, R. Moretti, T. Brown, J.P. Sundberg & P.A. Klein. 1995. Experimental transmission of green turtle fibropapillomatosis using cell-free tumor extracts. Diseases of Aquatic Organisms 22: 1-12.

Hoegh-Guldberg, O., P.J. Mumby, A.J. Hooten, R.S. Steneck, P. Greenfield, E. Gomez, C.D. Harvell, et al. 2007. Coral reefs under rapid climate change and ocean acidification. Science 318: 1737-1742.

Honarvar, S., M.C. Brodsky, E.P. Van Den Berghe, M.P. O’Connor & J.R. Spotila. 2016. Ecology of olive ridley sea turtles at Arribadas at Playa La Flor, Nicaragua. Herpetologica 72: 303-308.

Howard, R., I. Bell & D.A. Pike. 2014. Thermal tolerances of sea turtle embryos: Current understanding and future directions. Endangered Species Research 26: 75-86.

IPCC. 2007. Climate Change 2007: Impacts, Adaptation, and Vulnerability. Cambridge University Press: Cambridge, UK. 

Janzen, F.J. 1994. Climate change and temperature-dependent sex determination in reptiles. Proceedings of the National Academy of Science USA 91: 7487-7490.

Jensen, M.P., C.D. Allen, T. Eguchi, I.P. Bell, E.L. LaCasella, W.A. Hilton, C.A.M. Hoff, et al. 2018. Environmental warming and feminization of one of the largest sea turtle populations in the world. Current Biology 28: 154-159.

Karell, P., K. Ahola, T. Karstinen, J. Valkama & J.E. Brommer. 2011. Climate change drives microevolution in a wild bird. Nature Communications 2: 208. DOI: 10.1038/ncomms1213.

Konsta, A., A. Chatzimentor, M. Lin, C. Dimitriadis, A. Kyprioti, M. Liu, S. Li, et al. 2022. Marine heatwaves threaten key foraging grounds of sea turtles in Southeast Asian Seas. Regional Environmental Change 22: 97. DOI: 10.1007/s10113-022-01952-w.

Laloë, J.O., J. Cozens, B. Renom, A. Taxonera & G.C. Hays. 2014. Effects of rising temperature on the viability of an important sea turtle rookery. Nature Climate Change 4: 513-518.

Lamont, M.M. & I. Fujisaki. 2014. Effects of ocean temperature on nesting phenology and fecundity of the loggerhead sea turtle (Caretta caretta). Journal of Herpetology 48: 98-102.

Le Gouvello, D.Z.M., M.G. Hart-Davis, B.C. Backeberg & R. Nel. 2020. Effects of swimming behaviour and oceanography on sea turtle hatchling dispersal at the intersection of two ocean currents. Ecological Modelling 431: 109130. DOI: 10.1016/j.ecolmodel.2020.109130.

Lenton, T.M., J. Rockström, O. Gaffney, S. Rahmstorf, K. Richardson, W. Steffen & H.J. Schellnhuber. 2019. Climate tipping points – too risky to bet against. Nature 575: 592-595.

Limpus, C.J. & N. Nicholls. 1988. The Southern Oscillation regulates the annual numbers of green turtles (Chelonia mydas) breeding around northern Australia. Australian Journal of Wildlife Research 15: 157-161.

Maffucci, F., R. Corrado, L. Palatella, M. Borra, S. Marullo, S. Hochscheid, G. Lacorata & D. Iudicone. 2016. Seasonal heterogeneity of ocean warming: A mortality sink for ectotherm colonisers. Scientific Reports 6: 23983. DOI: 10.1038/srep23983.

Mancino, C., D. Canestrelli & L. Maiorano. 2022. Going west: Range expansion for loggerhead sea turtles in the Mediterranean Sea under climate change. Global Ecology and Conservation 38: e02264. DOI: 10.1016/j.gecco.2022.e02264.

Marshall, C.D., J.A. Cullen, M. Al-Ansi, S. Hamza & M.A.R. Abdel-Moati. 2020. Environmental drivers of habitat use by hawksbill turtles (Eretmochelys imbricata) in the Arabian Gulf (Qatar). Frontiers in Marine Science 7: 549575. DOI: 10.3389/fmars.2020.549575.

Mashkour, N., K. Jones, S. Kophamel, T. Hipolito, S. Ahasan, G. Walker, R. Jakob-Hoff, M. Whittaker, et al. 2020. Disease risk analysis in sea turtles: A baseline study to inform conservation efforts. PLOS ONE 15: e0230760. DOI: 10.1371/journal.pone.0230760.

Mazaris, A.D., A.S. Kallimanis, S.P. Sgardelis & J.D. Pantis. 2008. Do long-term changes in sea surface temperature at the breeding areas affect the breeding dates and reproduction performance of Mediterranean loggerhead turtles? Implications for climate change. Journal of Experimental Marine Biology and Ecology 367: 219-226. 

Mazaris, A.D., G. Matsinos & J.D. Pantis. 2009a. Evaluating the impacts of coastal squeeze on sea turtle nesting. Ocean & Coastal Management 52: 139-145.

Mazaris, A.D., A.S. Kallimanis, J. Tzanopoulos, S.P. Sgardelis & J.D. Pantis. 2009b. Sea surface temperature variations in core foraging grounds drive nesting trends and phenology of loggerhead turtles in the Mediterranean Sea. Journal of Experimental Marine Biology and Ecology 379: 23-27. 

Mazaris, A.D., A.S. Kallimanis, J.D. Pantis, & G.C. Hays. 2013. Phenological response of sea turtles to environmental variation across a species’ northern range. Proceedings of the Royal Society B: Biological Sciences 280: 20122397. DOI: 10.1098/rspb.2012.2397.

Meehl, G.A., W.M. Washington, W.D. Collins, J.M. Arblaster, A. Hu, L.E. Buja, W.G. Strand, et al. 2005. How much more global warming and sea level rise? Science 307: 1769-1772.

Miller, J.D. 1999. Determining clutch size and hatching success. In: Research and Management Techniques for the Conservation of Sea Turtles (eds. Eckert, K.L., K.A. Bjorndal, F.A. Abreu-Grobois & M. Donnelly). International Union for Conservation of Nature/Species Survival Commission Marine Turtle Specialist Group Publication No. 4. Pp. 124-129 

Milton, S.L. & P.L. Lutz. 2003. Physiological and genetic responses to environmental stress. In: The Biology of Sea Turtles Vol. 2. (eds. Lutz, P.L., J.A. Musick & J. Wyneken). CRC Press: Boca Raton FL, USA. Pp. 163-197.

Mobaraki, A., A.D. Phillott, M. Erfani, M. Ghasemi & H. Jafari. 2022. Inferred impacts of extreme environments on hawksbill turtle (Eretmochelys imbricata) body size and reproductive output. Chelonian Conservation and Biology 21: 187-198.

Momin, I.M., A.K. Mitra, J. Waters, D. Lea, M.J. Martin & R. Bhatla. 2022. Use and impact of satellite-derived SST data in a global ocean assimilation system over the tropical Indian Ocean. Journal of the Indian Society of Remote Sensing DOI: 0.1007/s12524-022-01586-9.

Montero, N., M.A.G. dei Marcovaldi, M. Lopez-Mendilaharsu, A.S. Santos, A.J. Santos & M.M. Fuentes. 2018. Warmer and wetter conditions will reduce offspring production of hawksbill turtles in Brazil under climate change. PLOS ONE 13: e0204188. DOI: 10.1371/journal.pone.0204188.

Montero, N., P.S. Tomillo, V.S. Saba, M.A.G. dei Marcovaldi, M. López-Mendilaharsu, A.S. Santos & M.M.P.B. Fuentes. 2019. Effects of local climate on loggerhead hatchling production in Brazil: Implications from climate change. Scientific Reports 9: 8861. DOI: 10.1038/s41598-019-45366-x.

Monsinjon, J., M. López-Mendilaharsu, P. Lara, A. Santos, M.A.G. dei Marcovaldi, M. Girondot & M.M.P.B. Fuentes. 2019. Effects of temperature and demography on the phenology of loggerhead sea turtles in Brazil. Marine Ecology Progress Series 623: 209-219.

Mortimer, J.A. 2012. Seasonality of green turtle (Chelonia mydas) reproduction at Aldabra Atoll, Seychelles (1980-2011) in the regional context of the Western Indian Ocean. Chelonian Conservation and Biology 11: 170-181.

Munday, P.L., P.J. Geoffrey, M.S. Pratchett & A.J. Williams. 2008. Climate change and the future for coral reef fishes. Fish and Fisheries 9: 261-185.

Neeman, N., N.J. Robinson, F.V. Paladino, J.R. Spotila, M.P. O’Connor. 2015. Phenology shifts in leatherback turtles (Dermochelys coriacea) due to changes in sea surface temperature. Journal of Experimental Marine Biology and Ecology 462: 113-120.

Newson, S.E., S. Mendes, H.Q.P. Crick, N.K. Dulvy, J.D.R. Houghton, G.C. Hays, A.M. Hutson, et al. 2009. Indicators of the impact of climate change on migratory species. Endangered Species Research 7:101-113.

O’Carroll, A.G., E.M. Armstrong, H.M. Beggs, M. Bouali, K.S. Casey, G.K. Corlett, et al. 2019. Observational needs of sea surface temperature. Frontiers in Marine Science 6: 420. DOI: 10.3389/fmars.2019.00420.

Patel, S.H., S.J. Morreale, V.S. Saba, A. Panagopoulou, D. Margaritoulis & J.R. Spotila. 2016. Climate impacts on sea turtle breeding phenology in Greece and associated foraging habitats in the wider Mediterranean region. PLOS ONE 11: e0157170. DOI: 10.1371/journal.pone.0157170.

Patel, S.H., M.V. Winton, J.M. Hatch, H.L. Haas, V.S. Saba, G. Fay & R.J. Smolowitz. 2021. Projected shifts in loggerhead sea turtle thermal habitat in Northwest Atlantic Ocean due to climate change. Scientific Reports 11: 8850. DOI: 10.1038/s41598-021-88290-9.

Patrício, A.R., L.A. Hawkes, J.R. Mosinjon, B.J. Godley & M.M.P.B. Fuentes. 2021. Climate change and marine turtles: Recent advances and future directions. Endangered Species Research 44: 363-395.

Patrício, A.R., M.R. Varela, C. Barbosa, A.C. Broderick, P. Carry, L.A. Hawkes, A. Regalla, et al. 2019. Climate change resilience of a globally important sea turtle nesting population. Global Change Biology 25: 522-535.

Pecl, G.T., M.B. Araújio, J.D. Bell, J. Blanchard, T.C. Bonebrake, I. Chen, T.D. Clark, et al. 2017. Biodiversity redistribution under climate change: Impacts on ecosystems and human well-being. Science 355: eaai9214. DOI: 10.1126/science.aai9214.

Phillott, A.D. & M.H. Godfrey. 2020. Assessing the evidence of ‘infertile’ sea turtle eggs. Endangered Species Research 41: 329-338.

Phillott, A.D. & A.F. Rees. 2021. Sea Turtles in the Middle East and South Asia Region. MTSG Annual Regional Report 2021. Draft Report to the IUCN-SSC Marine Turtle Specialist Group. 

Piao, S., Q. Liu, A. Chen, I.A. Janssens, Y. Fu, J. Dai, L. Liu, et al. 2019. Plant phenology and global climate change: Current progresses and challenges. Global Change Biology 25: 1922-1940.

Pike, D.A. 2009. Do green turtles modify their nesting seasons in response to environmental temperatures? Chelonian Conservation and Biology 8: 43-47.

Pike, D.A. 2013. Forecasting range expansion into ecological traps: Climate-mediated shifts in sea turtle nesting beaches and human development. Global Change Biology 19: 3082-3092. 

Pike, D.A., R.L. Antworth & J.C. Stiner. 2006. Earlier nesting contributes to shorter nesting seasons for the loggerhead sea turtle, Caretta caretta. Journal of Herpetology 40: 91-94.

Pilcher, N.J., M. Antonopoulou, L. Perry, M.A. Abdel-Latif, T.Z. Al Abdessalaam, M. Albeldawi, M. Al Ansi, et al. 2014. Identification of important sea turtle areas (ITAs) for hawksbill turtles in the Arabian Region. Journal of Experimental Marine Biology and Ecology 460: 88-99.

Plotkin, P.T. 2010. Nomadic behaviour of the highly migratory olive ridley sea turtle Lepidochelys olivacea in the eastern tropical Pacific Ocean. Endangered Species Research 13: 33-40.

Precht, W.F., B.E. Gintert, M.L. Robbart, R. Fura & R. van Woesik. 2016. Unprecedented disease-related coral mortality in Southeastern Florida. Scientific Reports 6: 31374. DOI: 10.1038/srep31374.

Quiñones, J., V.G. Carman, J. Zeballos, S. Purca & H. Mianzan. 2010. Effects of El Niño-driven environmental variability on black turtle migration to Peruvian foraging grounds. Hydrobiologia 645: 69-79.

Rafferty, A.R., C.P. Johnstone, J.A. Garner & R.D. Reina. 2017. A 20-year investigation of declining leatherback hatching success: Implications of climate variation. Royal Society Open Science 4: 170196. DOI: 10.1098/rsos.170196.

Rees, A.F., J. Alfaro-Shigueto, P.C.R. Barata, K.A. Bjorndal, A.B. Bolten, J. Bourjea, A.C. Broderick, et al. 2016. Are we working towards global research priorities for management and conservation of sea turtles? Endangered Species Research 31: 337-382.

Reid, K.A., D. Margaritoulis & J.R. Speakman. 2009. Incubation temperature and energy expenditure during development in loggerhead sea turtle embryos. Journal of Experimental Marine Biology and Ecology 378: 62-68.

Reina, R.D., J.R. Spotila, F.V. Paladino & A.E. Dunham. 2009. Changed reproductive schedule of eastern Pacific leatherback turtles Dermochelys coriacea following the 1997-98 El Niño to La Niña transition. Endangered Species Research 7: 155-161.

Saba, V.S., G.L. Shillinger, A.M. Swithenbank, B.A. Block, J.R. Spotila, J.A. Musick, et al. 2008. An oceanographic context for the foraging ecology of eastern Pacific leatherback turtles: Consequences of ENSO. Deep-Sea Research I 55: 646-660.

Sanderson, C.E. & K.A. Alexander. 2020. Unchartered waters: Climate change likely to intensify infectious disease outbreaks causing mass mortality events in marine mammals. Global Change Biology 26: 4284-4301.

Santidrián Tomillo, P., V.S. Saba, G.S. Blanco, C.A. Stock, F.V. Paladino & J.R. Spotila. 2012. Climate driven egg and hatchling mortality threatens survival of eastern Pacific leatherback turtles. PLOS ONE 7: e37602. DOI: 10.1371/journal.pone.0037602.

Santidrián Tomillo, P., M. Genovart, F.V. Paladino, J.R. Spotila, & D. Oro. 2015a. Climate change overruns resilience conferred by temperature-dependent sex determination in sea turtles and threatens their survival. Global Change Biology 21: 2980-2988.

Santidrián Tomillo, P., V.S. Saba, C.D. Lombard, J.M. Valiulis, N.J. Robinson, F.V. Paladino, J.R. Spotila, et al. 2015b. Global analysis of the effect of local climate on the hatchling output of leatherback turtles. Scientific Reports 5: 16789. DOI: 10.1038/srep16789.

Santidrián Tomillo, P., L.G. Fonseca, M. Ward, N. Tankersley, N.J. Robinson, C.M. Orrego, F.V. Paladino & V.S. Saba. 2020. The impacts of extreme El Niño events on sea turtle nesting populations. Climate Change 159: 163-176.

Sarmiento-Ramírez, J.M., J. Sim, P. Van West & J. Dieguez-Uribeondo. 2017. Isolation of fungal pathogens from eggs of the endangered sea turtle species Chelonia mydas in Ascension Island. Journal of the Marine Biology Association of the United Kingdom 97: 661-667.

Shillinger, G.L., E. Di Lorenzo, H. Luo, S.J. Bograd, E.L. Hazen, H. Bailey & J.R. Spotila. 2012. On the dispersal of leatherback turtle hatchlings from Mesoamerican nesting beaches. Proceedings of the Royal Society 279: 2391-2395.

Sullivan, B.K., S.M. Trevathan-Tackett, S. Neuhauser & L.L. Govers. 2018. Host-pathogen dynamics of seagrass diseases under future global change. Marine Pollution Bulletin 134: 75-88.

Tracy, A.M., M.L. Pielmeier, R.M. Yoshioka, S.F. Heron & C.D. Harvell. 2019. Increases and decreases in marine disease reports in an era of global change. Proceedings of the Royal Society B: Biological Sciences 286: 20191718. DOI: 10.1098/rspb.2019.1718. 

Umina, P.A., A.R. Weeks, M.R. Kearney, S.W. Mckechnie & A.A. Hoffman. 2005. A rapid shift in a classical clinical pattern in Drosophila reflecting climate change. Science 308: 691-693.

Valverde-Cantillo, V., N.J. Robinson, & P. Santidrián Tomillo. 2019. Influence of oceanographic conditions on nesting abundance, phenology and internesting periods of east Pacific green turtles. Marine Biology 166: 93. DOI: 10.1007/s00227-019-3541-1.

van de Geer, C.H., J. Bourjea, A.C. Broderick, M. Dalleau, R.S. Fernandes, L.R. Harris, G.E. Inteca, et al. 2022. Marine turtles of the African east coast: Current knowledge and priorities for conservation and research. Endangered Species Research 47: 297-331.

Wallace, B.P., A.D. DiMatteo, A.B. Bolten, M.Y. Chaloupka, B.J. Hutchinson, F.A. Abreu-Grobois, J.A. Mortimer, et al. 2011. Global conservation priorities for marine turtles. PLOS ONE 6: e24510. DOI: 10.1371/journal.pone.0024510.

Walther, G.R., E. Post, P. Convey, A. Menzel, C. Parmesan, T.J.C. Beebee, J.M. Fromentin, et al. 2002. Ecological responses to recent climate change. Nature 416: 389-395.

Walther, G.R. 2010. Community and ecosystem responses to recent climate change. Philosophical Transactions of the Royal Society B: Biological Sciences 365: 2019-2024.

Weber, S.B., J.D. Blount, B.J. Godley, M.J. Witt & A.C. Broderick. 2011. Rate of egg maturation in marine turtles exhibits ‘universal temperature dependence’. Journal of Animal Ecology 80: 1034-1041.

Weishampel, J.F., D.A. Bagley & L.M. Ehrhart. 2004. Earlier nesting by loggerhead sea turtles following sea surface warming. Global Change Biology 10: 1424-1427.

Weishampel, J.F., D.A. Bagley, L.M. Ehrhart & A.C. Weishampel. 2010. Nesting phenologies of two sympatric sea turtle species related to sea surface temperatures. Endangered Species Research 12: 41-47.

Yang, S., Z. Li, X. Hu, W. Dong & S. He. 2018. El Niño-Southern Oscillation and its impact in the changing climate. National Science Review 5: 840-857.