Thursday, March 8, 2012

What is a Kelt?

A bright Oregon coast steelhead
Credit: Ensteele/Creative Commons
Most of us have been taught that all salmon and steelhead die after spawning. It is the natural end to their life cycle. While this is true for salmon, steelhead are iteroparous (an animal that reproduces more than once) and can spawn two to three times in their life, returning to the ocean between each spawning event. “Kelt” is the term biologists use to describe an adult steelhead that has successfully spawned and is returning to the ocean.

When you stop and think about how long the journey is from the Pacific Ocean to spawning areas in the Clearwater drainage (upwards of 800 miles!) you can truly appreciate the strength and stamina a steelhead kelt must have in order to make the return trip. Due to predation, obstructions like dams, and poor body condition, many kelts don’t survive this return trip down stream.

Air-spawning a female steelhead at Dworshak National
Fish Hatchery
Credit: Angela Feldmann/USFWS
In order to encourage iteroparity in steelhead and to increase steelhead populations, fisheries biologists and managers with the Columbia River Inter-tribal Fish Commission (CRITFC) and the Nez Perce Tribe have developed several steelhead kelt reconditioning projects. The goal of kelt reconditioning is to restore post spawn steelhead by feeding and treating fish for disease so the fish can be returned to the river healthy, vigorous, and ready to spawn.
Steelhead being transferred into reconditioning tanks
Credit: Angela Feldmann/USFWS

One of CRITFC’s reconditioning projects is housed here at Dworshak National Fish Hatchery. Every January Scott Everett, a research biologist with Nez Perce Tribal Fisheries, can be found preparing large circular tanks with tall anti-jump curtains which will house up to 150 post- spawn adult steelhead. Female steelhead used for this project are spawned at Dworshak using low pressure compressed air. The air-spawning technique gently pushes the eggs out of the fish without harming her. After spawning fish are moved to reconditioning tanks where they will be fed, treated for disease, and monitored for growth and gonad development. If successfully reconditioned steelhead will be released 6-8 months later healthy and ready to spawn again!

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