Laura Erickson's For the Birds

Rats

Late this summer for a few days a rat appeared in my backyard, and I had to temporarily shut down my feeding station. Rats are a scourge in the urban environment—my dad was a Chicago firefighter who came home with horrifying stories about them that still make me shudder. But as terrible as rats are for us humans to cope with, they’re far worse in the natural environment. When they were brought to Hawaii, they wreaked havoc on these islands, bringing several ground-nesting species to their extinction by destroying the nests and eating the eggs and babies.

Rats also found their way, via humans, to Anacapa Island in Channel Islands National Park, in California. This island provides critical nesting habitat for some sea birds, including the endangered Xantus’s Murrelet, and the rats were well on their way to wiping out yet another species. The National Park Service developed plans to eradicate the rats, but the Fund for Animals brought suit against them to prevent this. But the American Bird Conservancy, the Pacific Seabird Group, the Endangered Species Recovery Council, and other groups intervened, and the Judge ruled in favor of the Park Service, enabling the Island Conservation and Ecology Group to eliminate the rats from the island.

I completely understand the aims and feelings of animal protection groups, having a hard time myself eating meat. When I look into the eyes of a mouse or gerbil I find mind and spirit looking back at me. My son Joey had a lovely rat named Ren for several years, and we valued her as a member of the family. But I am mystified why the Fund for Animals would have brought this lawsuit. Whether humans intervened or not, there were many animals suffering on Anacapa Island. Seabirds, native mice, salamanders and lizards were all dying in the face of the voracious rats, and had no defenses against them. And if we’d let nature take its course, after the rats wiped out the nesting colony and the other endemic animals, a large percentage of the rats would die of starvation. Sad as it was to eradicate these rats, it was sadder still that we’d allowed them to become established in the first place. We were the ones who opened Pandora’s box, and it was up to us to help the helpless native species we’d hurt through our carelessness.

Virtually instantly after the rats were eradicated, Xantus’s Murrelet rebounded. Radar studies show that nesting activity has increased markedly, and two nests have been found in locations where murrelets haven’t bred since the 1920s. Both these nests have hatchlings.

The Ashy Storm-Petrel is another bird that has benefited from the rat eradication program, and the island’s general diversity has been greatly enhanced. The number of birds visiting the nesting colonies has more than doubled, and animals native to the island, such as deer mice, side-blotched lizards, and slender salamanders, have also begun to rebound.

Rats weren’t introduced anywhere intentionally—they simply board ships and boats as stowaways. But people still are stupidly introducing animals here and there, often to provide temporary relief from another problem people caused in the first place. Those Asian ladybugs that seem to be everywhere right now were released intentionally by people who should have known better, to keep another insect pest down. You’d think that now that we are in the 21st Century we’d have figured out that even when an introduced species does what it’s supposed to and wipes out a pest, we end up with a very hungry species that’s bound to adapt and find another prey species.

Fortunately, we humans are supposed to be smart and adaptable, and may eventually stop fouling up Mother Nature’s plans. But at least on Anacapa Island we managed to get things back the way we found them.