This is Bird Note.

Cackling geese may look a lot like Canada geese,

but their slighter build and shorter beaks give them away as a distinct species.

And one subspecies in particular has a very special story.

Aleutian cackling geese filled their nests on a chain of islands off the western coast of Alaska.

In the 1700s, fur traders introduced an invasive species of fox to the islands,

with devastating consequences for the geese.

For decades, Aleutian cackling geese were believed to be extinct. But in the 1960s,

a biologist discovered a group of around 300 birds nesting on Bull Deer Island. The fortuitous

discovery allowed conservationists to put the birds on the endangered species list. And this paved the way for federal protections on their Alaskan nesting grounds

and their wintering territories in Oregon and California.

Thanks to this habitat conservation, there are now more than 120,000 allusion cackling geese,

making the biannual journey between Alaska and the Gulf of Mexico.

To learn how to conserve seasonal habitats and protect the future of migratory birds in your area,

start at our website, birdnote.org.

I'm Mark Bramhill.