The Rodents of the Farallons

at 12:35 AM
Save ArticleSave Article

Failed to save article

Please try again

I have had the good fortune to lead trips to the Galapagos Islands since 1991, where I've witnessed firsthand the devastation wrought on this fragile landscape by non-native, introduced animals. Millions of dollars donated by the international community has been spent to remove destructive dogs, cats, pigs, goats and rats. The immediate result is a return of native vegetation and a reprieve for giant tortoises, land iguanas and seabirds from possible extinction.

Recently I saw bright blue pellets of a rodenticide scattered everywhere on the Island of Sombrero Chino to eradicate rodents from that place. This process has been used prudently and repeatedly throughout the Galapagos with little detriment to other organisms.

Now, on our own Farallon Islands, the U.S. Fish and Wildlife Service has plans for eradicating European house mice by the same process. This proposal is heartening for the wild creatures that depend on the Farallons. And make no mistake; these islands harbor the largest seabird colony south of Alaska and are a vital component of the entire Eastern Pacific ecosystem. The mice threaten Ashy Storm Petrels. Half their entire population lives there, and every year mice destroy many of the eggs and young chicks. Burrowing owls now breed on the island due to those mice -- and unfortunately also feed on storm petrels.

WildCare, an animal rescue group from San Rafael, calls the proposal to eliminate mice "an absolute horror." The San Francisco Chronicle recently described the proposal as a "carpet bombing" of the Farallons.

Are rodenticides 100 percent safe and have absolutely no other effect on the ecosystem? No. But inflammatory speech masks the cool scientific analysis of cost and benefit. Accidentally introduced rodents have caused the extinction of many species worldwide. But in this case, the threatened ashy storm petrels, nesting on a handful of fragile islands, deserve our full protection.


The devoted scientists on the Farallons must be trusted to evaluate the risk to all animals and act appropriately. It's the right path.

This is Michael Ellis with a Perspective.