Pike's spread makes biologists change trout, salmon management

Posted: Thursday, August 17, 2000

ANCHORAGE (AP) -- From a distance, Andy Hawk thought the long, lean fish someone had tossed on the bank of Campbell Creek was a Dolly Varden char. After all, a Dolly was what an angler would expect to find in the cold, clear waters draining out of the Chugach Mountains into the heart of Anchorage.

As Hawk looked closer, he realized the coloration of this fish was all wrong. Silver-sided Dollies have greenish backs and pink spots. This fish was greenish with yellow spots in tigerlike strips above a white belly.

It quickly dawned on Hawk that the fish was something he never expected, or wanted, to see in an Anchorage salmon and trout stream.

A northern pike.

Hawk's report of pike in Campbell Creek this summer startled biologists with the state Department of Fish and Game. They since have been shocked to learn that the pike was not alone. There are others and, they believe, a good chance that pike populations are established in Campbell Lake -- possibly Taku Park Lake, too.

''Someone is probably sitting out there thinking, 'Well, it took them long enough' '' to figure this out, said area sportfisheries biologist Barry Stratton.

Fish and Game habitat biologist Steven Albert saw five or six pike in the creek earlier this month and examined a dead one on the bank near Nathan Road in Midtown. He talked to kids fishing the creek, who reported catching and landing another half-dozen.

Based on these reports, biologists say pike may be more widespread than they initially thought.

Pike might have been intentionally stocked in Campbell Creek by Midwestern anglers who like to catch the fish or by disgruntled Campbell Lake homeowners, who have opposed state efforts to stock silvers in the creek.

But there is a chance that these pike got into the creek accidentally, biologists say, and that has raised the specter of pike spreading across Southcentral Alaska, sharply limiting silver salmon and other species.

Some have fretted that this could lead to the decimation of the region's salmon runs. It won't, but some species, notably silver salmon, could be hit hard.

The Campbell Creek system offers an example of how that could happen.

''If (Campbell Lake) is infested,'' said Dave Rutz, the department's authority on pike, ''any coho that rear in that lake are going to be toast.''

Campbell Lake offers prime rearing habitat for young silvers. But if pike gain sway, everything from the slack waters of Campbell Lake to the swamps and beaver ponds behind the Tudor Track to the Campbell Creek waters in Bicentennial Park could be in danger, Stratton said.

If pike make it to the north fork of Campbell Creek, he fears a small run of sockeye salmon there could be rendered extinct.

Angry salmon anglers along with a fair number of biologists are ready to blame this all on some unknown Johnny Pikeseed infesting the region's waters with the toothsome predator popular among Midwestern anglers.

Rutz knows these anglers. He grew up catching pike in Minnesota before being lured north. He ended up in Alaska working with salmon, which led him back to pike studies.

The fish originated, he believes, with an illegal plant in Bulchitna Lake near Lake Creek and traveled out into the Yentna and Susitna rivers drainages.

It wasn't long before these predators were implicated as possible villains in the crash of king salmon runs in the popular Deshka River west of Willow. That's when Rutz started studying them.

His work largely freed the pike of blame for the king crash, but he discovered that pike decimated silver salmon fry and trout in dozens of Susitna Valley streams and lakes.

State stocking programs that pumped thousands of fingerling trout into Willow-area lakes to grow to catchable size for anglers had turned into pike-feeding programs.

The work by Rutz and other people led Fish and Game to abandon the popular put-and-take trout fisheries as a waste of time and money. Only recently has stocking resumed -- with a new twist.

Previously, the state planted trout and salmon fingerlings that would grow to catchable size, Rutz said. Now it plants catchable-size fish immediately available to anglers.

Fingerlings went looking for insects and other food in the same weedy shallows favored by pike, Rutz said. Few survived.

Larger trout and salmon, however, stay along the outer edges of the weeds, making it harder for pike to catch them.

Biologists also have discovered that salmon living in clear, fast-flowing waters or rocky lakes with steep shoreline gradients were almost immune to pike. The latter favor shallow, weedy waters over muddy bottoms.

So there is a natural limit to the amount of damage pike can do.

The problem is that much of the waters favored by pike also happen to be excellent rearing waters for silver salmon.

If there are pike there, Rutz said, the young silver salmon don't stand a chance. And lake fisheries, including the popular urban fisheries in Anchorage, become much harder and more costly to manage.

Stratton is convinced that some urban pike, such as those recently found in Cheney Lake, have been dumped in Anchorage waters.

Others could have gotten there accidentally, which raises interesting questions about spring pike fisheries and floatplanes in the Susitna Valley.

Just after ice-out is one of the best times to fish pike on the move to their spawning grounds.

Pike are open-water spawners, meaning the male and female get together and deposit eggs and milt above the lake bottom. The fertilized eggs then settle into the mud to incubate.

But what happens if a leaky float on a floatplane passes through a cluster of eggs?

Possibly disaster.

All sorts of exotic and invasive species of plants and animals have been moved to and around North America in ships' bilge water, which transplants the species when bilges are pumped.

Could the same thing happen when floats, which often have leaks, are pumped?

''That's never been proven,'' Rutz said, ''but it's always been suspected.''

There's another possibility.

Say someone went pike fishing during spawning season and caught several pike, male and female. The angler slides them into the float on his plane for the flight back to Anchorage. Eggs and milt squeeze out of the fish and mix in the water in the bottom of the float.

Once home, the floatplane angler takes the pike out of the float, making sure they're dead so there's no danger of a live fish escaping. Later, the pilot pumps the floats on the plane, never thinking that the lake might become contaminated with fertilized pike eggs.

This possibility makes Albert wonder whether there's more than coincidence to the appearance of pike in Campbell Lake and Fire Lake, another lake regularly used by floatplanes near Eagle River.

''My son's been catching pike in Fire Lake for years,'' Albert said.

His son and friends, worried about the health of the lake, at first tried to catch all of the pike in an effort to kill them off.

''He and his friends could never get them all,'' Albert said.

The kill-them-all-and-save-the-lakes theory also was tried in the Susitna Valley before Rutz's pike research was complete. He discovered the policy was counterproductive, in part because anglers were reluctant to kill every pike they caught and in part because it was impossible to catch every pike.

What usually happened, Rutz discovered, was that anglers kept the eating-size pike and threw the others back. Eventually, the lakes became full of small pike.

Those also happen to be the pike that are most efficient at catching and eating young trout and salmon. Biologists are experimenting with what are called ''slot limits'' on some lakes, including Alexander Lake at the head of Alexander Creek and Trapper Lake in the Deshka drainage.

In those lakes, anglers are allowed to keep as many pike as they want under 22 inches but only one over 30 inches long and none in the 22-inch to 30-inch size. The idea is to try to create a pike population in which cannibalistic pike feed significantly on one another.

Biologists believe that's one way to minimize pike predation. Meanwhile, they're fighting what appears to be a losing battle to stop the spread of pike into other waters.

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