Small Endemic Birds and Hot Climate: Avian and Environmental Predictors of Avifauna Road Mortality in Santa Cruz Galapagos.

Simple Summary: Simple Summary: Many bird species in the Galapagos Islands are killed on the roads by cars that transport citizens and tourists to their daily activities. This study reports the number of wild bird species killed near roads in 2004, 2005, 2006, and 2018 and uses a statistical analysis (PRIDIT) to rank the main intrinsic (avian) and extrinsic (environmental) predictors of mortality. About 250 birds (21 species) were found dead each year on the road. Our results show that for all studied years, small-endemic birds are especially at risk of roadkill during hot days on the main road of Santa Cruz. The Yellow Warbler Setophaga petechia aureola is the most affected species, particularly during the hot season. On the other hand, owls are a bigger species than the Yellow Warbler and, therefore, are less affected. However, the impacts of vehicle strikes are important to follow up on because owls are endangered. Although controlling the factors affecting bird mortality is complex, our results can inform management actions to mitigate avian mortality resulting from collisions with vehicles and other human activities. In the Galapagos Islands, the main road in Santa Cruz is one of the elements involved in bird road mortality along with vehicles and the impacted species. This study reports the number of roadkilled birds found on the road from the Itabaca Channel to Puerto Ayora, and the main factors, whether avian or environmental, involved in bird roadkill mortality. We collected individual carcasses in 2004, 2005, 2006, and 2018 with a prevalence of 278, 252, 265, and 294, respectively, across 21 species. The endemic Yellow Warbler Setophaga petechia aureola was the most affected bird. We used a PRIDIT model to rank the top avian and environmental predictors of road mortality. We found that for the sampled years, bird body size (i.e., 8–35 g) and the endemism status (i.e., endemic/native) were the main predictors of roadkill mortality, along with seasonality (i.e., hot season). Weaker predictors related to the bird (i.e., age and sex) and the environment (ecosystem, road slope, vegetation, or precipitation) are also reported as determinants of roadkill mortality. This study on avian mortality aims to inform conservation strategies to reduce the rate of wildlife avian roadkill on Santa Cruz Island and other islands with similar problems. [ABSTRACT FROM AUTHOR]