Feral cats (Felis catus) are among the most significant threats to island ecosystems, where they impact native fauna. On San Clemente Island (SCI), feral cats prey on the endemic deer mouse (Peromyscus maniculatus clementis) and island night lizard (Xantusia riversiana reticulata), the native side-blotched lizard (Uta stansburiana), and non-native black rats (Rattus rattus) and house mice (Mus musculus). Cats have been managed on SCI since at least 1989 through trapping and hunting, and since 2002 assessment of prey items from 5,342 removed cats has provided insight into their diets. We used generalized additive models to elucidate the relationship between cat dietary trends and vegetation productivity at different temporal lags using the Normalized Difference Vegetation Index (NDVI). Cats removed after periods of higher mean NDVI were more likely to contain rodents, while cats removed after periods of lower NDVI had a higher prevalence of lizards and fewer rodents. These results suggest, invasive cat diets are shaped by climatic variability affecting prey populations. If climate change alters local rainfall or other factors that influence vegetation productivity on SCI, understanding these dynamics will be crucial for informing adaptive management and protecting vulnerable native species.