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Great Lakes
Article:
Great Lakes 'legend' makes a comeback
After nearly disappearing, sturgeon thriving
Species has been around for 130 million years
By Pat Currie
Toronto Star
Published February 22nd, 2005
POINT EDWARD, Ont.—After decades of decline, a prehistoric
giant is reawakening in the deep waters of the Great Lakes.
The lake sturgeon, a fish that can grow to nearly three
metres and weigh 135 kilogram , has inspired legend worthy
of its size and extraordinary life.
In Algonquin mythology, a mighty sturgeon once swallowed
Hiawatha. And a British author and researcher has suggested
that the Loch Ness monster is really a giant sturgeon.
"They are creatures of legend," said commercial
fisherman Tim Purdy. "The biggest one we've ever
landed measured seven feet, nine inches and weighed 250
pounds. Biologists told us it was well over 100 years
old."
Nearly wiped out by overfishing at the turn of the century,
there is evidence this leviathan species, which is millions
of years older than the Great Lakes and rivers that sustain
it, is making a comeback.
"A lot of young sturgeon have been appearing in
southern Lake Huron. I think something is changing,"
said Purdy, whose family has been running a commercial
fishery on Lake Huron for four generations.
Next month, the U.S. Fish and Wildlife Service, which
lists sturgeon as a threatened species, will begin a three-year
project to see if the fish has returned to spawn on the
Saginaw River in Michigan.
River dams, logging operations that scoured river bottoms
and industrial pollution combined to eradicate most sturgeon
spawning grounds in the U.S.
The fish is not endangered in Canada but it's nowhere
nearly as plentiful as the monsters that were pulled ashore
in such numbers around 1900 "that they couldn't sell
them all and had to bury them in pits, my grandfather
told me," said retired Port Stanley commercial fisherman
Sam Vary.
The numbers continued to dwindle and bottomed out in
the 1980s but are now showing signs of recovering. The
St. Clair-Detroit River corridor contains 25,000 sturgeon,
the U.S. Wildlife Service estimates.
"There are tons of sturgeon in western Lake Erie,
especially around the mouth of the Detroit River,"
said Steve Vary, Sam's son. "They're always tearing
the hell out of our nets. I betcha there's a lot more
sturgeon there than they can imagine."
Lloyd Mohr, a spokesman with the natural resources ministry,
said the sturgeon "are probably holding their own,"
but he uses the word "recovery" with caution.
"We're seeing lots of small sturgeon on a regular
basis," said Mohr. "Maybe we're seeing more
of them because we're looking harder."
Small sturgeon are years from reaching reproductive age
so it may take 50 years for these youngsters to have an
impact, he said.
The typical lifespan of lake sturgeon is 55 years for
males and 80 to 150 years for females. Males spawn once
every two to seven years and females, beginning at 24
years of age, lay their eggs every four to nine years,
resulting in only 10 to 20 per cent of the population
spawning during a given year.
The lake sturgeon and its predecessors have been around
for 130 million years. The fish looks like a fossil sprung
to life, with a pointy mouth, jutting rows of armoured
plates and a distinct shark-like tail.
Despite its intimidating look and size, the sturgeon
is harmless. It has no teeth and feeds on the lake's bottom
on a diet consisting of insects, crustaceans, fish and
other organisms.
It may be that a recent invader of the Great Lakes has
fuelled the sturgeon's return.
"The sturgeon started appearing in greater numbers
just about the time the zebra mussels appeared in the
Great Lakes. We noticed that the sturgeons' stomachs were
full of crushed zebra-mussel shells," Purdy said.
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