Stay in the know about wildlife, water quality, and ecosystems on Sanibel and Captiva Islands and in Southwest Florida
Wildlife Changes Reflect Dynamic Nature of Barrier Islands
Wildlife recovery on Sanibel after the storm surge events of the last three years has been slow for many species. However, some species, like the invasive and exotic green iguana (Iguana iguana) and Peter’s rock agama (Agama picticauda), have exploded in number since Hurricane Ian for various reasons.
Native species, such as the raccoon (Procyon lotor), seemed to rebound quickly, whereas the Virginia opossum (Didelphis virginiana) appears to have been extirpated, or is no longer present.
“However, some species that had small, isolated populations appear to have endured, and in some cases expanded their range,” said SCCF Wildlife & Habitat Management Director Chris Lechowicz.
The gray squirrel (Sciurus carolinesis) was documented in several neighborhoods on the island well before Hurricane Ian.
It is not a true historic native resident of Sanibel, although it is found on the mainland of Lee County. These squirrels were undoubtedly brought to the island with tree plantings from off-island nurseries and likely on other vehicles from time to time.
“The preferred habitat on Sanibel appeared to be residential areas where they established small colonies,” said Lechowicz. “We have had no reports of them on conservation lands.”
Their presence adds another prey item for raptors, bobcats (Lynx rufus), coyotes (Canis latrans), and coachwhip snakes (Masticophis flagellum) that may exist or pass through neighborhoods.
With the minuscule but slowly recovering populations of marsh rabbits (Sylvilagus floridanus) on the island still being insignificant, gray squirrels are likely giving predators more prey options.
“The impetus to writing on this topic was due to a recent drive on the east end of the island where I had to slam on my brakes to avoid hitting a gray squirrel that was quickly crossing near Periwinkle Way and Skiff Place,” added Lechowicz. “It reminded me of other species I now see more frequently post-Ian, such as agamas, and curly-tailed lizards (Leiocephalus carinatus), and even green iguanas.”
Species abundances and ranges have shifted as habitats have changed, allowing some species to be more successful than others. This is yet another example of how dynamic barrier islands can be over time.