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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.)

Although elasmobranchs (sharks and rays) are highly threatened by fisheries, there are few studies that examine gear and fishery effects on catch composition and abundance across India, one of the top elasmobranch fishing nations globally. We assessed elasmobranch diversity, abundance, catch rates and fishery characteristics using landing surveys in Malvan on the central-western coast of India, a major multi-gear, multi-species fishing centre, over three sampling periods from February 2018 to March 2020. We sampled 3145 fishing trips and recorded 27 elasmobranch species, of which nearly half are categorised as "Threatened" by the IUCN. In addition, we documented historical records by compiling information from identification guides, research papers, articles and reports. During the study period, the catch was dominated by small-sized coastal species like the spadenose shark (Scoliodon laticaudus) and the scaly whipray (Brevitrygon walga). Trawlers accounted for 64.9% of the catch, highest by number, and captured smaller-sized individuals. Nonetheless, artisanal and gillnet fisheries had higher catch per unit effort (CPUE) for rays (5.1 ± 1.0) and sharks (10 ± 1.0), respectively, and captured significantly larger-sized individuals. Through generalised linear models, we found seasonal, gear and fishery effects on the abundance and size of commonly caught species. The presence of neonates and gravid females of multiple species also suggests nursery grounds in this region. Historically, 141 species have been recorded in this region, and a comparison with current catch suggests a shift in elasmobranch community structure and potential mesopredator release. This study emphasises the importance of gear and species-specific research for conservation planning at the local level and suggests the need for management strategies with fisher cooperation., (© 2023 Fisheries Society of the British Isles.)