GEOGRAPHIC RANGE
Island spotted skunks (Spilogale gracilis amphiala) are small carnivores that live only on Santa Cruz and Santa Rosa, two islands in the Channel Islands archipelago off the coast of California, USA. These striking, yet cryptic mammals may have also lived on nearby San Miguel Island, but haven't been seen there since the late 19th century.
Spotted skunks probably colonized the Channel Islands over 9,000 years ago, when the sea level was lower than it is today. Back then, Santa Cruz, Santa Rosa, San Miguel, and Anacapa Islands were connected, forming a super-island called Santarosae.
Scientists aren't sure how spotted skunks first reached Santarosae Island. Humans might have brought them over on purpose thousands of years ago, or perhaps they drifted over from the mainland accidentally on debris after a storm. It seems unlikely that a tiny mammal could cross 6 or more miles of open ocean, but a single pregnant female skunk carried on a raft of vegetation would have been enough to start a new population on Santarosae.
Beginning in the 1850s, wildlife habitats on Santa Cruz and Santa Rosa islands were affected by intensive ranching, feral pigs, and introduced deer. But spotted skunks clung to existence on these islands, likely retreating to small patches of habitat that remained in steep, remote canyons.
By the mid-2000s, livestock and big game mammals had been removed from all three islands. Native vegetation and wildlife (like the island fox) began to recover. But for reasons scientists don't fully understand, island spotted skunks seem to be about as rare as they were in the early 1990s, when sheep, pigs, and deer still roamed the denuded islands.
