New squirrels on the block? Not so fast, researchers say

Arctic ground squirrel photographed on Chirikof Island in July 2013. (Photo courtesy of Patrick Saltonstall)
In recent decades, researchers around the world have become increasingly concerned about the introduction of invasive species to islands.
Some species, like cattle and foxes, were intentionally introduced to Gulf of Alaska islands and have wreaked havoc on ecosystems.
Biologists assumed that settlers also brought Arctic ground squirrels to Gulf of Alaska Islands around the turn of th