This is just one post in the Invasive Species Category

Hatchery victim of mussels; Quagga infestation to be costly burden on operation, officials say

Posted by: Aqua Blog Maven on May 9, 2008 at 2:22 pm

From the Las Vegas Review-Journal:

They’ve already caused operators of dams and hydroelectric plants on the lower Colorado River system to brace for millions of dollars in maintenance and repair costs. And they’ve frustrated boaters in the Lake Mead National Recreation Area as millions of them cling to vessel hulls and engine cooling water intakes.A nd now, invasive quagga mussels, which were discovered in Lake Mead’s Boulder Basin on Jan. 6. 2007, are starting to clog up the works at the Willow Beach National Fish Hatchery.

The federal hatchery, where thousands of rainbow trout and endangered fish are raised, is on the Arizona side of Lake Mohave, 14 miles southeast of Hoover Dam.

“The problem is that anywhere there is no (strong) flow, quagga mussels will establish themselves in the screens, pipes, wood boards and walls of the raceways,” hatchery manager Mark Olson said. As he spoke Wednesday, one of his co-workers for the U.S. Fish and Wildlife Service, Mark Yost, used a power washer to blast quagga mussel shells off a drained concrete channel, or raceway, where rainbow trout once swam.

The problem stands to be as prolific as the reproduction rate of the pesky mollusks themselves. Since the first quagga shell was found at the hatchery a little more than a year ago, millions more have multiplied.

Olson said the hatchery, where 300,000 rainbow trout and 20,000 endangered razorback suckers and 35,000 bonytail chub are raised, faces a problem that could cost $2 million to $5 million to fix if the facility is converted to well water or a treated water supply that is free of quaggas, unlike raw water from Lake Mohave that is used for most hatchery operations.

The quagga problem in the Colorado River basin could be even worse than the Great Lakes:

Because of ideal conditions in the lakes on the lower Colorado River system with the right mix of food, calcium, dissolved oxygen and water temperature, quaggas have a reproduction rate three times that of those in the Great Lakes region. They reproduce six times a year instead of two, and a single female lays as many as 1 million eggs.

Once colonies are established, they can clog water lines and cause pumps to overheat.

Of the $600,000 that’s budgeted annually to operate the 45-year-old hatchery, no money is devoted to dealing with clogged pipes and equipment, Olson said. The problem “is indefinite,” he said. “I don’t see it going away. They didn’t go away in the Great Lakes. We just have to come up with a management strategy that works and stick with it.”