<img height="1" width="1" style="display:none" src="https://www.facebook.com/tr?id=192888919167017&amp;ev=PageView&amp;noscript=1">
Friday, March 29, 2024
March 29, 2024

Linkedin Pinterest

Release of Klamath Basin suckers could save species

Infusion of juvenile fish into lake aims to avoid extinction

By HOLLY DILLEMUTH, Herald and News, Herald and News
Published: March 24, 2018, 5:00pm

KLAMATH FALLS, Ore. — It isn’t easy being a Klamath Basin sucker.

There has been a 75 percent decline in populations of two endangered Klamath Basin sucker species over the past two decades, and juvenile fish are not surviving beyond their first year of life, according to U.S. Fish and Wildlife. As part of an effort to keep the species from extinction, officials are releasing upward of 2,500 hatchery-reared juvenile sucker into Upper Klamath Lake over the next couple of weeks.

Alan Mikkelsen, senior adviser to Secretary of the Interior Ryan Zinke on water and Western resources, stood boots deep just off the boat ramp at Eagle Ridge County Park on Tuesday morning, lowering the first of many Lost River and shortnose sucker to be released into the murky waters of Shoalwater Bay on Upper Klamath Lake.

Mikkelsen, who said he took the Interior job after semi-retiring as a fishing guide in Idaho, said he normally catches and releases steelhead and salmon, but that the release of sucker holds more weight in this scenario.

“What’s going on here is an attempt to stabilize and ultimately increase the population of sucker in the lake, both Lost River and shortnose sucker, we would really like to get to a point where the Klamath Tribes will have their traditional and cultural history restored and where irrigators will be able to also irrigate,” Mikkelsen said, following the release.

“We will be in a position to release double this much next year, and we hope to double it a year after that,” Mikkelsen added.

At least 17,000 shortnose and 43,000 Lost River sucker, 60,000 total, need to be released annually in order to sustain populations of the fish at current levels, according to Evan Childress, U.S. Fish and Wildlife fish biologist.

Mikkelsen said he hopes to increase that number to as much as 100,000 sucker.

“This is one of the only options left for helping these fish survive or bringing them back from the brink of extinction,” said Susan Sawyer, public affairs officer for the U.S. Fish and Wildlife Service’s Pacific Southwest region, which includes the Klamath Basin.

The 2-year-old cohort is the first of its age group to be released, having been reared from the larval stage at the Gone Fishing facility outside of Klamath Falls. Upward of 2,500 2-year-old juvenile sucker are set to be released in Pelican Bay near Rocky Point within the next couple weeks, according to Sawyer.

“The valedictorians, they got to go first,” Sawyer said, referencing the release. “This first class is going to give us a lot of information.”

U.S. Fish and Wildlife released a group of 14-month-old sucker in 2017, but never have a cohort of 2-year-old, captivity-reared Klamath Basin sucker been released.

Each 2-year-old sucker being released is implanted with a Passive Integrated Transponder — a PIT — that tracks the fish. The U.S. Geological Survey will collect signals from each fish using an antenna, Sawyer said, as they pass mostly through the Williamson and Sprague rivers. This will help determine survival rates. It is estimated that 15 percent of the 2,500 released this year could survive.

U.S. Fish and Wildlife won’t be able to detect large numbers of the released fish for up to two years, Childress said, when the fish will likely spawn.

Sucker released after Tuesday will be released largely in the evening to mitigate predators feasting on the newly freed fish, and in groups of 40 to 50 at a time.

The fish are camouflaged, especially in murkey water, but still look like “tasty morsels” to birds, according to Childress, which led the agency to release them earlier in the year to allow the fish to get their bearings before more potential predators arrive in the Basin.

Sucker released this week have been raised from the larval stage and started out growing up in warmer temperatures in outdoor ponds during the winter.

Childress said geothermally heated ponds at Gone Fishing allow U.S. Fish and Wildlife to keep fish warmer in the winter in captivity, which helps with higher growth rates for the sucker population.

The species have been acclimated to decreased water temperatures before being released, Childress said.

“There’s no shock,” Childress said. “It’s not like they’re going from the hot tub to the swimming pool.”

Loading...