Rainbow trout at Lee’s Lake – 04/06/2004

http://www.crowsnestpasspromoter.com/story.php?id=96595
By Tami Van Dusen
Reporter

Crowsnest Pass Promoter — Rainbow trout at Lees Lake have died of
natural causes this winter.

Reports of many of the fish washing up dead on the shores this winter
led area fisheries biologist Daryl Wig to take a closer look at the
situation. It’s reassuring to know that the fish haven’t been the
victim of anything other than nature’s own process, he says.
“It’s sort of a typical thing,” he said. “We’ve no reason to suspect
anything different.”

Growing plants give off plenty of oxygen. When they start to die, the
decomposing plants give off less oxygen. That means less air for the
fish to breathe, which is what happened at Lees Lake.
But, according to reports from anglers, the catch rate from Lees Lake
is still “fairly good,” indicating that the fish population is doing
okay, says Wig.

Another thing that could cause a winter fish kill is a sudden
overabundance of plant growth in a lake caused by, for example,
increased fertilizer from nearby farms or ranches. That hasn’t
happened in this case, said Wig.

A third cause of winterkill is extremely thick ice or heavy snow on a
lake, which also didn’t happen at Lees Lake this winter. The lake is
about 45 feet deep at the west-end and 10-15 feet deep in most other
areas.

While winterkill of fish isn’t uncommon, the fact that it has
happened at Lees Lake is uncommon. The last incident occurred in the
winter of 1978-79, says Wig. Other lakes in the area have had
winterkill, including Phillips Lake which is located high on the
other side of the Crowsnest Range.