Invasive Crayfish Found In Southern Oregon, Omnivores That Prey On Native Crayfish, Salmon Eggs

Photo: Michael Parker

Northern crayfish were found in the Ashland canal, marking the first documented existence of this non-native species in Oregon.

Native to the Midwest, invasive populations of Northern crayfish exist in California and Washington.

This discovery could be bad news for Oregon’s native signal crayfish – Northern crayfish are much more aggressive. And as omnivores, they can prey on signal crayfish, the eggs of salmon and steelhead, and consume native vegetation.

Because Ashland canal leads to Bear Creek and the Rogue River, Rick Boatner, ODFW’s Invasive Species Coordinator, says Northern crayfish have the potential to duplicate what rusty crawfish did in the John Day River Basin.

It is believed rusty crayfish were released in the John Day River near Mitchell by a school group about 42 years ago. These crayfish have since taken over most of the river from native signal crayfish and are predicted to enter the Columbia River by 2025. Signal crayfish are now displaced and rarely seen today.

Although the Ashland canal can have low stormwater levels, crayfish can burrow in mud and wait for higher water. They can also travel over land to other water bodies.

Boatner and his team will begin surveying selected areas of the canal starting above Emigrant Reservoir to Lithia Park and trapping any Northern crayfish found. If the species is established, Boatner says they are most likely here to say and will continue to spread in the Rogue River Basin.

If anyone knows of a crayfish release in the Ashland area, please contact Boatner at 503-947-6308. Schools are reminded that classroom specimens cannot be released into the wild; a permit is required to import non-native crayfish into Oregon.  Aquarium fish and other pets are also not allowed to be released. These actions can cause significant harm to Oregon’s native fish and wildlife species.

People are encouraged to report invasive fish and wildlife to

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