Great Lakes
Article:
States to slash salmon stocking in
Lake Michigan
By Dan Egan
Milwaukee Journal Sentinel
Posted on Bradenton.com on November 15, 2005
MILWAUKEE - Lake Michigan's popular chinook salmon stocking
program will be throttled back next year due to plummeting
numbers of alewives - the Pacific salmon's favored food
- and mounting evidence that large numbers of chinook
are now reproducing naturally in lake tributaries.
The states of Wisconsin, Michigan, Indiana and Illinois
will slash their combined planting program by 25 percent,
from 4.3 million to about 3.3 million, the Wisconsin Department
of Natural Resources announced Tuesday.
Reductions in annual plantings have in the past been
greeted with suspicion by angler groups, but state fishery
managers from around the region made a good case for the
switch before those groups at a meeting held in Kenosha
earlier this fall.
"I sensed there was strong support from angler groups
to cut lake-wide stocking overall. I thought the message
was well received," said DNR biologist Paul Peeters.
"(But) I do think there was some angst among sporstsmen
about where the cuts would be."
To hold up its end of the agreement, Wisconsin will drop
its chinook plantings next spring by 21 percent, or about
300,000 fish.
Lake Michigan's salmon program started in the 1960s with
the dual goal of controlling the invasive alewives and
to give a boost to recreational fishing on the big lake.
The states' combined stocking programs peaked in the
late '80s with about 8 million chinook planted annually,
but those programs were dramatically reduced after massive
salmon die-offs due to disease. Biologists say that disease
was likely tied to malnutrition - the lake could not support
the amount of chinook being planted.
Chinook plantings were reduced further in 1999 to just
more than 4 million annually.
The problem is the lake's alewife population has continued
to plummet. A study released this spring showed the lake's
adult alewife population dropped by about 70 percent between
the fall of 2003 and 2004, and today the lake's alewife
population is perhaps 5 percent of what it was in the
1960s.
One theory behind the recent drop-off in alewives is
the Atlantic natives can't handle the Great Lakes' temperature
swings. Some scientists also think the decline may be
at least partially tied to a drop in food for the alewives
called diporeia. That shrimp-like creature has disappeared
from vast expanses of the lake bottom since the arrival
of the invasive zebra mussel.
Meanwhile, evidence suggests that as much as 50 percent
of Lake Michigan's chinook population is now reproducing
on its own - something never expected when the stocking
program began.
Most, if not all, of that natural reproduction is occurring
in the cold and relatively clean streams and rivers of
Michigan.
"It's critical the states work together to manage
the fishery, so I'm pleased we were able to reach agreement,"
Mike Staggs, Wisconsin DNR fisheries director, said in
a news release. "Natural reproduction of chinook
has improved tremendously in Michigan streams in recent
years, and the result of this good news and other factors
is that there are too many fish for the forage base to
support. We think the lake-wide reduction will help sustain
the fabulous fishing anglers have enjoyed in recent years."
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