Friday, March 14, 2014

Oregon Chub Recovery

 Oregon chub, which are found exclusively in Oregon's Willamette Valley, were listed as "endangered" under the Endangered Species Act in 1993. In 2014, they qualified for delisting under the Act, the first fish in the United States to achieve this status.

 An inconspicuous minnow that inhabits the backwaters of the Willamette Valley gained national prominence when it became the first fish in the United States meet its recovery goals under the federal Endangered Species Act.

Oregon chub are likely one of Oregon’s least known fish species because of their size and where they are found.  Oregon chub are small; they reach a maximum length of three inches, and they are not targeted by anglers as sport or food fish.

Over the past 100 years, many of these habitats were destroyed by the construction of dams, channelization of streams and draining of wetlands. These habitat losses, combined with the introduction of non-native fish that preyed on and competed with chubs for food, resulted in a sharp decline in their abundance.

“Oregon chub are like the ultimate underdogs,” said Paul Scheerer, ODFW Oregon Chub Project leader, who has devoted the past 22 years of his professional life to recovering the tiny fish. “Not many people know what they’re looking at when they see one, including some biologists.”

When Oregon chub were listed as “endangered” under the ESA in 1993 the population had declined to under 1,000 fish in eight known locations, down from at least 29 locations historically.

The listing triggered a multi-agency campaign to recover the Oregon Chub population. The now 22-years-long recovery program included better monitoring, working with landowners to secure new habitat, improving floodplain management and transplanting fish to more than 20 new locations.

When a multi-agency task force known as the Oregon Chub Working Group met in 2012 to review the numbers they concluded the populations were large, stable and dispersed enough to warrant a closer look at delisting the fish.  A follow-up review of the numbers a second time, in 2013, confirmed their earlier finding – the populations had grown to approximately 160,000 fish in 83 locations.

Under the criteria set in the Oregon Chub Recovery Plan there needed to be at least 20 populations of at least 500 adults, with each population stable or increasing in abundance for seven years. In addition, these populations needed to be dispersed with at least four populations each in three Oregon river basins – the Middle Fork Willamette, Santiam, and main stem Willamette.

Recovery was also due to the efforts of the Oregon Chub Working Group, which was formed in 1992, with representatives from the FWS, ODFW, U.S. Army Corps of Engineers, the U.S. Forest Service, Oregon State Parks, Oregon State University, the McKenzie River Trust, Grand Ronde Tribe and others.

The Oregon chub (Oregonichthys crameri) is one of several chub species in Oregon.  Two of them – Borax Lake chub and Hutton tui chubs – are protected under the ESA. Others, including Alvord chub, blue chub, Umpqua chub, and several additional subspecies of tui chub, are not listed.

For more information, visit ODFW’s Oregon chub webpage.

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