Effect of the invasion history of the giant African snail (Lissachatina fulica) on its realized climatic niche

There is almost a century of difference among Indo-Malayan, Australasian, and Neotropical regions in establishment of non-native populations of the giant African snail (Lissachatina fulica). Using potential distribution models and environmental principal component analysis (PCA-env), we first tested whether an expansion of the realized climatic niche of L. fulica occurred. The models showed geographical differences between the native and non-native areas, especially in the Neotropical region, where the last introduction of mollusks occurred. Because PCA-env showed a 60% expansion and 40% overlap between the native and global areas, we next investigated whether the expansion of the realized climatic niche of L. fulica was influenced by its geographical spread. Precipitation had the highest contribution in most models, but temperature was the variable that best explained the projected spread from the current Neotropical distribution. The current Neotropical distribution was better explained when the climatic conditions of the Indo-Malayan and Australasian regions from which the species arrived in the Neotropics were included. PCA-env showed 74% expansion between the native and Indo-Malayan-Australasian areas and 97% expansion between the native and Neotropical areas. In conclusion, the spread between biogeographic regions and the existence of similar climatic conditions between the native and non-native distributions would produce the observed climatic niche of L. fulica.

Automated summary

There is a significant time difference in the establishment of non-native populations of the giant African snail in different geographic regions. Using distribution models and environmental analysis, researchers found that the expansion of the snail's climatic niche was influenced by its spread and that temperature played a key role in explaining its distribution in the Neotropical region.