# Heat Nests: The Impact of Climate Change on Loggerhead Turtle (Caretta caretta) Nesting Distribution in Sicily (Italy)

## TL;DR

This study examines how climate change is affecting where loggerhead sea turtles nest in Sicily, showing a northward shift due to rising temperatures.

## Contribution

The study provides updated nesting site data and uses SDMs to show climate change's impact on loggerhead turtle distribution in Sicily.

## Key findings

- Loggerhead turtle nests are increasingly found along Sicily's northern coast due to rising temperatures.
- Most nests are concentrated along the southern and eastern coasts, with numbers increasing over recent years.
- Many nests occur outside protected areas, indicating a need for expanded conservation efforts.

## Abstract

This study aims to update and establish a comprehensive list of nesting sites in Sicily and its minor islands, investigate the distribution and environmental suitability of the loggerhead sea turtles' nesting in Sicily using spatial distribution models (SDMs), and perform a gap analysis considering the protected area network in Sicily. Location: Sicily (Italy). Time period: 1979–2022. Data on Loggerhead seaturtle's nests were collected through several sources, including literature, monitoring records from WWF's Progetto Tartarughe, reports from the local fauna haunting, online articles, referrals on websites and social networks often related to monitoring activities. GIS was used to realize distribution maps. Bioclimatic indicators were downloaded through Copernicus Climate Change Service. Predictors were eventually projected on the WorldClim's dataset. Suitability distribution models (SDMs) were realized using the maximum entropy model (MaxEnt software).
Caretta caretta
's nests distribution map and environmental suitability map were overlaid with the Natura 2000 sites map in Sicily. The results confirm that the main nesting areas are mostly concentrated along the southern and eastern coasts of Sicily, with increasing numbers observed over recent years. Additionally, global warming has made some beaches even more suitable along the north coast of the main island. The variable affecting this species the most is the Mean Temperature of the Coldest Quarter (Bio11). Overlaying nesting distribution and environmental suitability maps with Natura 2000 sites revealed significant portions of nests occurring outside protected areas, highlighting the need for expanded conservation efforts.The demographic increase of nesting events in Sicily is induced by a northward shift of the species distribution led by rising temperatures and probably due to climate change.

To establish and update the list of nesting sites in Sicily and its minor islands. To investigate the Sicilian distribution and nesting suitability using spatial distribution models (SDMs). Performing a gap analysis in a GIS environment considering the protected area network in Sicily.