NANFA-- Ravenous Sunnies

M. Mickelson (
Thu, 25 Sep 2003 10:12:02 -0500

Scientists to Probe Sunfish, Mosquitos

By JAY LINDSAY, Associated Press Writer

BOSTON - The tenacity with which the banded sunfish devours mosquito
larvae is described by scientist Bill Mebane by evoking an image of a
starving man set loose in a yard buried in popcorn.

The banded sunfish is so ravenous that some scientists think it could be
the perfect mosquito killing machine, potentially putting a major dent
in the pest's East Coast population.

This summer, researchers at the Marine Biological Laboratory at Woods
Hole revived dormant research into using the fish for mosquito control.

The fish could infiltrate remote areas that are difficult to reach with
the larvicide widely used today, providing more effective control for
less money and blunting the reach of mosquito-borne diseases like the
West Nile virus (news
earch/news?p=%22West%20Nile%20virus%22&c=&n=20&yn=c&c=news&cs=nw> - web
arch?cs=nw&p=West%20Nile%20virus> sites).

Massachusetts hasn't approved any fish for mosquito control, though
other states use them. Mebane said state officials must be convinced the
fish won't wreak havoc on the local ecology.

"If they're comfortable the fish isn't going to present any danger to
other fish, then we're onto something good," Mebane said.

But Tom French, assistant director of the state Division of Fisheries
and Wildlife, said researchers must do more than prove the sunfish won't
do harm - they'll also have to show they'll do significant good in the
fight against mosquitos. That may be more difficult.

French said mosquito-eating fish native to the South haven't made much
difference, even though they school in much greater density than banded

"I'm extremely skeptical that there's any promise in what they're trying
to do," French said. "(Banded sunfish) may eat mosquitos, but not in a
quantity that's going to matter."

Gabrielle Sakolsky of the Cape Cod Mosquito Control Project has been
working on finding the right mosquito-eating species for Massachusetts
since the mid-1990s.

She knew the fish had to be native to Massachusetts so it didn't
threaten indigenous species. It also had to thrive in shallow water with
low oxygen content, where mosquito larvae are often found. The banded
sunfish fit the bill.

The fish, found from southern New Hampshire to Florida, ranges in color
from olive green to pale brown with five to eight vertical bands on the
body. As Mebane describes it, the two- to three-inch long fish is
essentially built to eat mosquito larvae. It has a tiny mouth, moves
quickly and can maneuver through shallow areas. It also does better than
most species in acidic water, as evidenced by its prevalence in the
highly acidic waters of New Jersey's Pine Barrens.

Sakolsky had found her fish, but had no expertise in collecting or
breeding it. That's where Mebane, an aquaculturist, entered the picture
after being introduced to Sakolsky by a colleague.

Some early research was completed in 1995, but that quickly ended
because of lack of funding.

"We were excited about it," Mebane said. "Everyone was excited about it.
But it never went any further."

The project was revived this spring with a one-year, $7,000 grant from
the Southeastern Massachusetts Aquaculture Center. Scientists harvested
the fish in a local cranberry bog this spring. On Thursday, the fish are
being placed in cages in the bog to see how they survive the winter.

Scientists need to know more about what the sunfish eat so they can
determine how a wide release would affect other species that eat the
same foods, Sakolsky said.

They also need to know more about their reproduction. Mebane said he
hopes the sunfish needs fairly specific water conditions to reproduce.
That way, they can be widely distributed in various water conditions
without worrying about a population explosion.

Early results indicate the banded sunfish reproduce best in water that's
acidic and soft, like a cranberry bog, Mebane said.

"If we can prove these sunfish are limited in their ability to
reproduce, that would really be perfect," he said.

Any time you begin to feel REALLLY powerful, try telling a cat what to
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