The Oregon chub is a tiny fish, only growing about 3.5 inches long. But thanks to an unlikely 21-year comeback from the brink of extinction, it's suddenly kind of a big deal.

The minnow may soon be the first fish to come off the U.S. endangered species list because it has recovered, the Fish and Wildlife Service announced Tuesday. Until now, the only way fish had escaped the list was through taxonomic revision or extinction.

"This is an excellent example of how the Endangered Species Act is intended to function — partners working together to recover an endangered species," U.S. Fish and Wildlife Service (FWS) Director Dan Ashe said in a statement Tuesday. "This is a tremendous success that came about from a great vision and a lot of hard work on behalf of the Service and our partners at the Oregon Department of Fish and Wildlife and the U.S. Army Corps of Engineers, as well as private landowners and many others."

The Oregon chub exists nowhere but the Willamette River Basin, where it historically inhabited a network of swampy side channels, river bends and overflow ponds. Periodic flooding would create new habitat, and even helped the fish establish new populations. A few hundred years ago, as many as 1 million Oregon chub plied the region's waters.

But dams and flood-control projects transformed the Willamette River last century, wiping out many chub habitats and restricting the fish to just a few streams and rivers. When it was added to the U.S. endangered species list in 1993, only eight known populations of Oregon chub remained, representing fewer than 1,000 individuals.

Willamette River

The Willamette River near West Linn, Ore. (Photo: Noël Zia Lee/Flickr)

The U.S. government published a recovery plan in 1998, focusing on ways to rebuild habitat and reintroduce the fish to places it once lived. That meant lots of collaboration: The FWS began working with local agencies and landowners to restore chub habitats, and with the U.S. Army Corps of Engineers to model dam releases after natural water-flow patterns. It also released captive-bred chubs into the wild, striking deals with private landowners to ensure the fish's return wouldn't become an economic burden.

"The partnership with the [FWS] was instrumental in Oregon chub recovery efforts," says Roy Elicker, director of the Oregon Department of Fish and Wildlife. "Their funding of monitoring and restoration activities, combined with the coordination of the safe-harbor agreement to protect landowners, are big reasons why we're celebrating this recovery."

The Oregon chub had expanded to 38 known populations by 2007, and in 2010 it was downlisted from "endangered" to "threatened." With roughly 150,000 individuals now living in at least 80 different locations, it's poised to become the 27th species — and the first fish — saved from extinction by the 40-year-old U.S. Endangered Species Act.

The FWS now has up to a year to finalize its proposal to delist the species, a decision it says "will be based on the best scientific and commercial data available." A 60-day public comment period also begins Feb. 6 to let the public review and discuss the fish's fate. Although few Americans are familiar with the Oregon chub, experts say its importance goes beyond the symbolism of America's first fish to be saved from near-extinction.

"While the chub isn't an iconic fish species that many think about in the Pacific Northwest, it is a very important part of the ecosystem and indicator of good water quality and ecosystem health," says Paul Henderson, state supervisor for the Oregon Fish and Wildlife Office. "By successfully recovering the chub, we're helping many iconic wildlife species and improving the watershed for all Oregonians."

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Russell McLendon ( @russmclendon ) writes about humans and other wildlife.

U.S. endangered species list finally saves a fish
The Oregon chub would be the first U.S. fish to lose its endangered status because it's no longer at risk of extinction.