The study conducted by our external associate researcher, Katherine Simbaña, examined anticoagulant rodenticides (ARs) in California king snakes in Gran Canaria, an invasive species subject to a control plan involving capture and euthanasia. Ten ARs, mainly second-generation compounds, were identified in 90% of the analyzed snakes, with brodifacoum being the most common. Surprisingly, over 50% of the studied snakes showed exposure to multiple compounds. The research revealed a correlation between the size and geographic location of the snakes and higher AR concentrations, indicating potential patterns in the distribution of these compounds. The results suggest that California king snakes could serve as sentinel species for monitoring ARs in the ecosystem, especially in relation to birds of prey on the island.
The study addresses the widespread use of anticoagulant rodenticides (ARs) for rodent population control, emphasizing their threat to non-target wildlife. ARs are categorized into first-generation anticoagulants (FGARs) and second-generation anticoagulants (SGARs), differing in toxicity, half-life, and resistance. Both types cause coagulopathy by inhibiting vitamin K1 and clotting factors, with SGARs being more effective but also more hazardous to the environment.
The document highlights that many non-target species, including mammals, birds, and reptiles, are exposed to ARs, leading to adverse effects on their health and survival. The importance of wildlife biomonitoring studies is emphasized to assess the presence and impact of ARs in the environment, safeguarding biodiversity and human health. Additionally, the utility of invasive snakes, such as the California king snake in Gran Canaria, as sentinel species for assessing contaminant exposure is discussed, particularly in comparison to raptors in the same region with similar feeding habits. The study aims to characterize the exposure of these snakes to ARs, identify geographical and biometrical factors influencing exposure, and explore their potential as sentinel species in comparison to raptors.
You're invited to read more about this research here: https://pubmed.ncbi.nlm.nih.gov/37996022/