New Publication on Sea Turtles range expansion!

Santidrián Tomillo, P., Tomás, J., Marcos, A., Panagopoulou,A. and Tavecchia,G. 2022 Enviornmental changes in the Mediterranean Sea could facilitate the western expansion of loggerhead turtles. MEPS DOI: https://doi.org/10.3354/meps14149

ABSTRACT: Climate change may affect life on Earth in multiple ways. Whereas some populations may encounter detrimental conditions that cause extirpations, those occupying cooler thermal limits of a range may benefit by expanding. For sea turtles, egg maturation in the female oviduct and nest incubation are temperature-dependent and vulnerable to climate change. 

Mediterranean loggerhead turtles Caretta caretta nest in the eastern basin although sporadic nesting occurs on the western side. To assess the likelihood of a climate-related expansion, we compared historical air and sea surface (SST) temperatures between locations near established eastern nesting areas and western areas where sporadic nesting is increasing (Palinuro, Italy) or just started (Balearic Islands, Spain). Our results suggest that summer air and water temperatures in western sites were suitable for nesting over the last 40-50 yr, at least in July-August, having (1) SSTs above suboptimal threshold temperature (22°C) and (2) similar air temperatures to those of Greece, but among the lowest in the Mediterranean. There was a decreasing east-to-west gradient in SST. However, SSTs were similar around beaches of Zakynthos (Greece), Palinuro and Ibiza (Balearic Islands), where SST was above 22°C for at least 60 d, potentially allowing turtles to lay multiple clutches. A warming trend was detected in air temperature and SST since the 1970s-1980s. Although conditions in the western Mediterranean currently seem suitable for nesting, lower air temperatures in May-June and higher precipitation in September could shrink the nesting window. If warming continues, conditions in the western basin could progressively become more favorable for nesting. 

New publication on climate change and bird breeding phenology!

Mingozzi, T., Storino, P., Venuto, G., Massolo, A., Tavecchia, G., 2021. Climate warming induced a streth of the breeding season and an increase of second clutches in a passerine breeding at its altitude limits. Current Zoology, zoab029, https://doi.org/10.1093/cz/zoab029

Abstract: The increase in the average air temperature due to global warming has produced an early onset of the reproduction in many migratory birds of the Paleartic region. According to the “mismatch hypothesis” this response can lead to a decrease in the breeding output when the conditions that trigger the departure from the wintering areas do not match the availability of food resources in the breeding ground. We used 653 brooding events registered during the period 1991–2013 to investigate the link between climatic variables and individual breeding performance of a partially migratory passerine, the Rock SparrowPetronia petronia, breeding at the altitude limit of its distribu-tion.

 

Photo: Corrado Damiano

The laying date (LD) of the earliest first clutch was associated with local spring (minimum) temperatures but did not show a significant trend during the period considered. The LD of the latest first clutch had a positive and statistically significant trend, unrelated to local covariates and resulting in a longer breeding season (1.5 days/year). A longer breeding season allowed birds to produce more second clutches, which proportion increased from 0.14 to 0.25. The average breeding success was also positively correlated with the average temperature in July and with the duration of the breeding season. Contrary to expectations, the most important climate-dependent effect was a stretch of the breeding season due to a significant increase of the LD of the latest first-clutches rather than an earlier breeding onset. We show how climate changes act on bird populations through multiple paths and stress the need to assess the link between climatic variables and several aspectsof the breeding cycle.

New publication on seabird phenology and climate change !

Keogan, K., Daunt, F. [...], Igual, J.M. [...], Sanz-Aguilar, A. [...], Lewis, S. 2018. Global phenological insensitivity to shifting ocean temperatures among seabirds. Nature Climatre Change 8,313–318 doi:10.1038/s41558-018-0115-z

Photo: from CEHseabirds

Abstract: Reproductive timing in many taxa plays a key role in determining breeding productivity, and is often sensitive to climatic conditions. Current climate change may alter the timing of breeding at different rates across trophic levels, potentially resulting in temporal mismatch between the resource requirements of predators and their prey. This is of particular concern for higher-trophic-level organisms, whose longer generation times confer a lower rate of evolutionary rescue than primary producers or consumers. However, the disconnection between studies of ecological change in marine systems makes it difficult to detect general changes in the timing of reproduction. Here, we use a comprehensive meta-analysis of 209 phenological time series from 145 breeding populations to show that, on average, seabird populations worldwide have not adjusted their breeding seasons over time (−0.020 days yr⁻¹) or in response to sea surface temperature (SST) (−0.272 days °C⁻¹) between 1952 and 2015. However, marked between-year variation in timing observed in resident species and some Pelecaniformes and Suliformes (cormorants, gannets and boobies) may imply that timing, in some cases, is affected by unmeasured environmental conditions. This limited temperature-mediated plasticity of reproductive timing in seabirds potentially makes these top predators highly vulnerable to future mismatch with lower-trophic-level resources.