Natural History Wanderings

The San Francisco Chronicle reports

There are so many mice on the Farallon Islands that sometimes the ground appears to be undulating, a gently rolling tide of rodents.

The mice do not belong on the Farallones, an archipelago 27 miles off the coast of San Francisco. They are tiny interlopers, descended from the escapees off seal-hunting ships in the 1800s. Since then, they have proliferated. There are tens of thousands of them, converging on what scientists say is one of the highest densities of rodents anywhere in the world.

They eat insects, depriving native salamanders of their diet. Owls come to the islands to eat the mice, and then start preying on the Ashy storm petrel, half of whose global population of 8,000 lives in the Farallones. They’re spreading invasive plants on their fur, too.

Read full story at: Is mass poisoning the only way to solve the Farallon Islands’ overwhelming rodent problem? – SFGate