[mou] Die-off of Waterbirds Underway on Lake Onalaska/Upper Pool 8
Jim Barrett
jwbarrett10@msn.com
Mon, 11 Apr 2005 21:39:05 -0500
This is a multi-part message in MIME format.
------=_NextPart_000_0004_01C53EDE.E2AA4A80
Content-Type: text/plain;
charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable
This news release was forwarded to me by a friend who is a waterfowl =
biologist for the MN-DNR. Another warning about exotics. For another =
article dealing with exotics in the Great Lakes ecosystem, which =
appeared in the Duluth News Tribune recently, see the link at the bottom =
of the page.
Jim Barrett
Duluth, MN
(news release begins here)
U.S. Fish & Wildlife Service
News Release
National Wildlife=20
Refuge System
Upper Mississippi River National Wildlife and Fish Refuge
La Crosse District =20
555 Lester Avenue
Onalaska, WI 54650
=20
FOR IMMEDIATE RELEASE Contact: Jim =
Nissen (608) 783-8401
April 5, 2005 =
=20
=20
Die-off of Waterbirds Underway on=20
Lake Onalaska/Upper Pool 8
=20
Sick and dead lesser scaup, coots, and ring-necked ducks are being found =
on Lake Onalaska and along the main channel immediately below Lock and =
Dam 7 near Dresbach, Minn. Higher river flows are moving some of the =
birds through the dam and depositing them along the main channel in the =
upper part of Pool 8. Intestinal parasites, known as trematodes or =
flukes, are believed to be the cause of this die-off. =20
Trematode-caused waterfowl and coot mortality has been documented each =
spring and fall on Lake Onalaska since the 2002 spring migration. =
During the 2004 spring migration, about 1,060 sick/dead birds were found =
and total mortality was estimated at 2,400 to 2,700. Comparable losses =
occurred during the 2004 fall migration. Mortality this spring was =
first observed on March 28 and is expected to continue through the end =
of April. =20
Carcasses are being shipped to the U.S. Geological Survey's National =
Wildlife Health Center in Madison, Wisc. for examination. =20
Most trematodes have complex life cycles that require two intermediate =
hosts in which the parasites develop before they become infective for =
the definitive, final bird host. At least two different species of =
trematodes have been found in the digestive tracts of birds involved in =
past die-offs. Both species are small, ranging in size from 1 =
millimeter to less than 2 millimeters. =20
Last summer and early fall, parasitologists from the National Wildlife =
Health Center and Minnesota State University at Mankato, Minn. sampled =
snails in selected areas of Lake Onalaska. Among the findings, an =
exotic snail, known as the faucet snail (Bithynia tentaculata), is now =
present in the river and serves as the first and second intermediate =
host for both species of trematodes. A portion of the snails collected =
and examined from various sites on Lake Onalaska were infected with the =
trematodes. =20
Based on a review of the literature, this snail appears to be a newcomer =
to the Upper Mississippi River. Native to Europe, faucet snails were =
first found in Wisconsin in the Great Lakes basin in the early 1900's. =
In 1998, these snails were documented in Shawano Lake. Die-offs of =
coots and lesser scaup from trematodes closely parallel locations within =
Wisconsin where faucet snails have been found. =20
Depending on how heavily snail populations are infected, some birds can =
receive a lethal dose during less than 24 hours of feeding. Susceptible =
waterfowl can die 3-8 days after ingesting a lethal dose of the =
trematodes. =20
Avian predators and scavengers, such as bald eagles, crows, and gulls, =
have been feeding on the sick/dead birds. Mammals, such as raccoons and =
coyotes, may also be feeding on the carcasses. According to Wildlife =
Disease Specialists, there appears to be no documented threat that =
raptors or scavengers feeding on infected carcasses are at risk.
For more information, or to report finding sick or dead waterfowl or =
coots in areas other than Lake Onalaska, contact the La Crosse District =
Office of the U.S. Fish and Wildlife Service at 608/783-8405.
(end of news release)
Related article: =
http://www.duluthsuperior.com/mld/duluthsuperior/2005/04/02/news/11291508=
.htm
=20
=20
=20
=20
------=_NextPart_000_0004_01C53EDE.E2AA4A80
Content-Type: text/html;
charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML><HEAD>
<META http-equiv=3DContent-Type content=3D"text/html; =
charset=3Diso-8859-1">
<META content=3D"MSHTML 6.00.2800.1491" name=3DGENERATOR>
<STYLE></STYLE>
</HEAD>
<BODY bgColor=3D#ffffff>
<DIV><FONT face=3DArial size=3D2>This news release was forwarded to me =
by a friend=20
who is a waterfowl biologist for the MN-DNR. Another warning about =
exotics. For another article dealing with exotics in the Great=20
Lakes ecosystem, which appeared in the Duluth News Tribune =
recently, see=20
the link at the bottom of the page.</FONT></DIV>
<DIV><FONT face=3DArial size=3D2></FONT> </DIV>
<DIV><FONT face=3DArial size=3D2>Jim Barrett</FONT></DIV>
<DIV><FONT face=3DArial size=3D2>Duluth, MN</FONT></DIV>
<DIV><FONT face=3DArial size=3D2></FONT> </DIV>
<DIV><FONT face=3DArial size=3D2>(news release begins =
here)</FONT></DIV>
<DIV><FONT face=3DArial size=3D2></FONT> </DIV>
<DIV><FONT face=3DArial size=3D2>U.S. Fish & Wildlife =
Service</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=3DArial size=3D2>News Release</FONT></DIV>
<DIV><FONT face=3DArial size=3D2></FONT> </DIV>
<DIV><FONT face=3DArial size=3D2>National Wildlife </FONT></DIV>
<DIV><FONT face=3DArial size=3D2></FONT> </DIV>
<DIV><FONT face=3DArial size=3D2>Refuge System</FONT></DIV>
<DIV><FONT face=3DArial size=3D2></FONT> </DIV><FONT face=3DArial =
size=3D2>
<DIV><BR>Upper Mississippi River National Wildlife and Fish Refuge</DIV>
<DIV> </DIV>
<DIV>La Crosse District </DIV>
<DIV> </DIV>
<DIV>555 Lester Avenue</DIV>
<DIV> </DIV>
<DIV>Onalaska, WI 54650</DIV>
<DIV> </DIV>
<DIV> =
</DIV>
<DIV> </DIV>
<DIV>FOR IMMEDIATE=20
RELEASE =
&=
nbsp; =20
Contact: Jim Nissen (608) 783-8401</DIV>
<DIV> </DIV>
<DIV>April 5,=20
2005 &nb=
sp; &nbs=
p;  =
; =
&=
nbsp; &n=
bsp; =20
<BR> </DIV>
<DIV> </DIV>
<DIV>Die-off of Waterbirds Underway on </DIV>
<DIV> </DIV>
<DIV>Lake Onalaska/Upper Pool 8</DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV>Sick and dead lesser scaup, coots, and ring-necked ducks are being =
found on=20
Lake Onalaska and along the main channel immediately below Lock and Dam =
7 near=20
Dresbach, Minn. Higher river flows are moving some of the birds =
through=20
the dam and depositing them along the main channel in the upper part of =
Pool=20
8. Intestinal parasites, known as trematodes or flukes, are =
believed to be=20
the cause of this die-off. </DIV>
<DIV> </DIV>
<DIV>Trematode-caused waterfowl and coot mortality has been documented =
each=20
spring and fall on Lake Onalaska since the 2002 spring migration. =
During=20
the 2004 spring migration, about 1,060 sick/dead birds were found and =
total=20
mortality was estimated at 2,400 to 2,700. Comparable losses =
occurred=20
during the 2004 fall migration. Mortality this spring was first =
observed=20
on March 28 and is expected to continue through the end of April. =
</DIV>
<DIV> </DIV>
<DIV>Carcasses are being shipped to the U.S. Geological Survey=92s =
National=20
Wildlife Health Center in Madison, Wisc. for examination. </DIV>
<DIV> </DIV>
<DIV>Most trematodes have complex life cycles that require two =
intermediate=20
hosts in which the parasites develop before they become infective for =
the=20
definitive, final bird host. At least two different species of =
trematodes=20
have been found in the digestive tracts of birds involved in past=20
die-offs. Both species are small, ranging in size from 1 =
millimeter to=20
less than 2 millimeters. </DIV>
<DIV> </DIV>
<DIV>Last summer and early fall, parasitologists from the National =
Wildlife=20
Health Center and Minnesota State University at Mankato, Minn. sampled =
snails in=20
selected areas of Lake Onalaska. Among the findings, an exotic =
snail,=20
known as the faucet snail (Bithynia tentaculata), is now present in the =
river=20
and serves as the first and second intermediate host for both species of =
trematodes. A portion of the snails collected and examined from =
various=20
sites on Lake Onalaska were infected with the trematodes. </DIV>
<DIV> </DIV>
<DIV>Based on a review of the literature, this snail appears to be a =
newcomer to=20
the Upper Mississippi River. Native to Europe, faucet snails were =
first=20
found in Wisconsin in the Great Lakes basin in the early 1900=92s. =
In 1998,=20
these snails were documented in Shawano Lake. Die-offs of coots =
and lesser=20
scaup from trematodes closely parallel locations within Wisconsin where =
faucet=20
snails have been found. </DIV>
<DIV> </DIV>
<DIV>Depending on how heavily snail populations are infected, some birds =
can=20
receive a lethal dose during less than 24 hours of feeding. =
Susceptible=20
waterfowl can die 3-8 days after ingesting a lethal dose of the=20
trematodes. </DIV>
<DIV> </DIV>
<DIV>Avian predators and scavengers, such as bald eagles, crows, and =
gulls, have=20
been feeding on the sick/dead birds. Mammals, such as raccoons and =
coyotes, may also be feeding on the carcasses. According to =
Wildlife=20
Disease Specialists, there appears to be no documented threat that =
raptors or=20
scavengers feeding on infected carcasses are at risk.</DIV>
<DIV> </DIV>
<DIV>For more information, or to report finding sick or dead waterfowl =
or coots=20
in areas other than Lake Onalaska, contact the La Crosse District Office =
of the=20
U.S. Fish and Wildlife Service at 608/783-8405.</DIV>
<DIV> </DIV>
<DIV>(end of news release)</DIV>
<DIV> </DIV>
<DIV>Related article: <A=20
href=3D"http://www.duluthsuperior.com/mld/duluthsuperior/2005/04/02/news/=
11291508.htm">http://www.duluthsuperior.com/mld/duluthsuperior/2005/04/02=
/news/11291508.htm</A><BR> <BR> <BR> <BR> <BR></DIV><=
/FONT></BODY></HTML>
------=_NextPart_000_0004_01C53EDE.E2AA4A80--