See the following post from Dr. John Hartig. Are any
fisheries researchers looking at the possible link between global climate
change and the warmer lake temperatures during the spring and summer months as
a possible cause? If so, please let me know. Thanks!
To: Refuge Partners
From: John Hartig
Subject: Michigan DNR News Release About Muske Die-Off
See attached news release about Muske die-off
FOR IMMEDIATE RELEASE
> April 25, 2006
> Contacts: Gary Towns 734-953-0241 or Mary Dettloff 517-335-3014
> Muskellunge Die-Off in Southeast Michigan Being Monitored
> A significant number of muskellunge, the second largest game fish in
> Michigan, have been observed dead over the last month in Lake St. Clair
> and the St. Clair and Detroit rivers, according to Department of Natural
> Resources fisheries biologists. The die-off is being monitored by the DNR
> and volunteer groups in the area.
> "Any time a significant number of fish die, we are concerned for the
> resource and monitor the situation closely to determine the factors behind
> it," said Gary Towns, DNR Lake Erie Management Unit supervisor.
> the current situation has likely been caused by a combination of factors
> which have impacted the muskies in the area."
> Towns said the DNR has essentially ruled out pollution as a factor.
> said species such as walleyes, emerald shiners and other minnows, which
> are more sensitive to pollution, do not seem to have been affected.
> Anglers are currently catching lots of walleye, bass and other species
> which appear to be very healthy, Towns added.
> DNR fisheries officials feel the die-off of muskellunge could have been
> caused by several factors including a combination of spawning stress, a
> warmer winter which may have set the stage for a higher incidence of
> disease, and recent rapid warming of water over the past several weeks.
> It is unknown if the bacterial disease first detected in Lake St. Clair
> muskellunge in 2002, known as musky pox (Piscirickettsia sp.), is
> involved. Fish with visible signs of musky pox have red rashes and sunken
> Towns said the muskies that are being found in Lake St. Clair and the
> Detroit River appear to have died about a month ago and were likely on the
> bottom of the lake and river system. As they have been decomposing, they
> have floated to the surface of the water, he said. Due to the
> decomposition, DNR pathologists cannot test the fish for musky pox or
> other diseases. Only live fish or fish that have been dead for less than a
> few hours can be tested for bacterial or viral diseases, Towns said.
> The rapid warming of the water in the St. Clair River and Lake St. Clair
> area could be a major factor, Towns said. Normally in late April,
> water temperatures are in the mid-40s. Towns said that presently the
> water temperatures are in the low to mid-50s, and some anglers have
> reported water temperatures in isolated bays in the 60 degree range.
> Rapid water temperature changes can put a lot of stress on fish, he said.
> In terms of musky pox, Towns said while many muskies may be infected with
> it, the disease is usually only fatal to a few fish. Musky pox could cause
> the death of some fish when the fish are under stress, for example during
> the spring when water temperatures can warm rapidly.
> The DNR has contacted Canadian fisheries officials to monitor their side
> of Lake St. Clair and the St. Clair River as well, and they have reported
> some dead muskellunge, too. While a musky die-off was observed in
> spring of 2003, very few dead muskies were reported in 2004 and 2005.
> "We want area anglers to know that we are aware of the problem and we
> appreciate their reports of dead muskies in the waters of the St. Clair
> River, the Detroit River and Lake St. Clair," Towns said. "We
> monitoring the situation to determine the extent of the die-off, however;
> we feel at this time it is a combination of weather, spawning
> perhaps some disease factors which have affected the fish."
> The DNR is committed to conservation, protection, management, use and
> enjoyment of the state's natural resources for current and future
John H. Hartig, Refuge Manager
Detroit River International Wildlife Refuge
Large Lakes Research Station
9311 Groh Road
Grosse Ile, MI 48183
Thomas K. Rohrer, Asst.
Prof. & Director
318 Brooks Hall
Central Michigan University
U. S. A.
Ph. (989) 774-4409
email = firstname.lastname@example.org
CMU Environmental Studies Program
information is available at:
"Never doubt that a small group of thoughtful,
committed people can change the world: indeed it is the only thing that
-- Margaret Meade
“Far better it is to dare mighty things, to win
glorious triumphs, even though sometimes checkered by failure, than to take
rank with those poor spirits who neither enjoy much nor suffer much.....because
they live in that gray twilight that knows not victory nor defeat.”