With the Fourth of July Holiday approaching, state parks and forestry officials are reminding people that fireworks are prohibited in state parks and forests, and they are also reminding people that anyone responsible for starting a wildfire can be held liable not only for any damage done by the fire, but also for the cost of controlling the fire. Fire danger levels were at the moderate level across the state this week, but officials remain especially concerned about the 14,400 acres of woodlands in Shawano, Langlade, Menominee, Oconto and Marinette counties that was damaged in a June 7 tornado. Much of the down timber is drying out and the combination of dried fuel on the ground and downed timber making access difficult would make fighting fires in this area very complicated. Residents in the areas damaged by the tornado should avoid burning and not use any fireworks because of the fire danger in that area.
Much of the state received only minimal precipitation in the last week, though areas of southwestern and north central Wisconsin did receive an inch or more of rain. Many popular northern canoeing and kayaking rivers are running very low, making paddling difficult. The Bois Brule River in Douglas County was running at record lows for this time of year. The Flambeau and Chippewa rivers were also running very low.
Fish have moved into summer patterns on most inland lakes across the state, but fishing generally remains good. Smallmouth bass, northern pike and musky fishing were all good. Panfish spawning is completed and panfish have moved out to deeper water and were suspending near thermoclines. Bluegill fishing was great on many southern lakes last week, with nice catches of bluegills caught around weeds in 5 to 15 feet of water. Crappies were being caught suspended above weeds. Musky action has also been excellent on many waters, with surface baits and large jerk baits producing action.
Walleye and catfish fishing in the Fox River has been extremely productive. Walleye action was very good on Lake Winnebago and out on Green Bay, where some large 26- to 30-inch walleyes were brought in during a weekend tournament. Perch fishing continued to be great on the east shore of the bay. Anglers trolling out on Lake Michigan had a good week of weather producing many good trips. Anglers reported good catches of chinook salmon, rainbow trout, and an increase in the number of coho salmon caught. Shore anglers in Milwaukee have been catching good numbers of perch.
Pheasant chicks are hatching. The young from second clutches of rabbits and squirrels are venturing from their nests.
With the passing of the summer solstice, bird nesting season is in full swing. Most migrants are feeding young and some have even fledged youngsters from the nest already. Recently fledged young include reports of Baltimore orioles, golden-winged warblers, and house wrens. While summer has just officially begun some species of shorebirds willalready begin their “fall” migration in another week or two. Birdwatchers should have good luck observing these species at places like the Ashland lakefront, Crex Meadows, Rainbow Flowage, and Horicon Marsh.
Prairie flowers in bloom include: coreopsis, white indigo, beardtongue, coneflower, black-eyed susan, spiderwort, purple prairie clover, St. Johnswort, and hoary vervain. And with butterfly weed also in bloom some of the butterflies being observed include cabbage white, Milbert’s tortoise shell, red admiral, tiger swallowtail, painted lady, and the endangered Karner Blue.
A three-minute audio version of this report can be heard by calling (608) 266 2277.
A new report is put on the line each week.
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Statewide Birding Report
With the onset of the summer solstice nesting season is in full swing. Most Neotropical migrants are feeding young and some have even fledged youngsters from the nest already. Recently fledged young include reports of Baltimore orioles, golden-winged warblers, and house wrens. Other interesting nesting reports include a large brood of pintails at Zeloski Marsh Wildlife Area and a pair of male Henslow's sparrows in Florence County. There's still time for birders to enjoy the late nesting season as birds will be attempting second broods and leading recently fledged young around new territories as they leave the nest. "Fall" shorebird migration will begin in a week or so and birders should have good luck at places like Crex Meadows, Ashland lakefront, Rainbow Flowage, Horicon Marsh and Zeloski Marsh Wildlife Area. Laughing and little gulls still persist along the Lake Michigan lakeshore. As always, please report sightings to ebird (
www.ebird.org/WI) to help better track bird populations.
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NORTHERN REGION
Superior DNR Service Center area
Brule River State Forest - Thanks to the collaboration of The Conservation Fund and Wausau Paper Mills a total of 5,889.13 acres of property have been added to the Brule River State Forest. To commemorate this event Gov. Jim Doyle made an appearance at the Brule DNR office Wednesday June 27 to announce this and other land purchases across the state which totaled over 10,000 acres. He declared June 27 Wisconsin Stewardship Day. Summer flowers continue to put on a show in the Brule area. Cow parsnip, st. john's wort, meadow rue, showy lady's slipper, figwort, water hemlock, four-o'clock, elderberry, and winterberry have started blooming now. The Bois Brule River is flowing at record low flow for this time of year. As of June 28, the river was flowing at 113 cubic feet per second (cfs). The 62 year average is 149 cfs. With the Fourth of July coming up, the Brule DNR fire control staff remind people to celebrate responsibly. Some areas have not received as much rain as other places. Make sure that all campfires are totally out and cold when not attended.
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NORTHEAST REGION
Green Bay DNR Service Center area
Brown County - Walleye fishing on the bay was tremendous over the weekend. With temps in the 80s, blue skies and low winds, the conditions were right to be out fishing. Some of the larger walleyes reported at the tournament over the weekend were 8 to 10 pound and 26 to 30 inches. Most of the walleyes were between 17 to 24 inches. Shore fishing in on the Fox continued to have a steady bite of catfish, drum, some walleye, white bass and the occasional northern and musky. Shore fishing along Duck and Suamico creeks wase still producing catches of cats and drum. Perch fishing continued to be great on the east shore. Although recent insect hatches and abundance of baitfish have seemed to disperse fish at various depths and locations, once found anglers do well. The perch harvests seem to be higher the farther north you go starting at bay shore park. Some of the largest perch are 12 to 14 inches and around a pound. Most of the perch are 7-9inches and great eaters. Some perch and smallmouths were being caught in little sturgeon bay, most on live bait and early in the day. Sawyer harbor remains slow although some nice bass were scattered.
Manitowoc County - Fishing in Manitowoc was once again great for trout and salmon anglers this past week. Anglers trolling out on Lake Michigan had a good week of weather producing many good trips. Anglers reported good catches of Chinook salmon, rainbow trout, and an increase in the number of Coho salmon caught. Anglers fishing from the south pier had a fair week with one or two nice kings being caught off the pier during most early morning trips. The average sizes of fish caught this week were Chinook salmon 7 to 16 pounds, rainbow trout 6 to 8 pounds, and Coho salmon 4 to 7 pounds. In Two Rivers, anglers trolling out on Lake Michigan had a great weekend with many successful trips. Most boats trolled between 60 and 80 feet of water with the most action off lines set 30 to 40 feet down. Anglers were picking up many nice Chinook and Coho salmon and rainbow and lake trout. Anglers fishing off the piers had a slow week for salmon while fishing inside the harbor was excellent for bullhead anglers. The larger Chinook caught were around 18 pounds with lengths of 35 inches. The rainbow trout that were landed were near 10 pounds.
Sturgeon Bay DNR Service Center area
Door County - The week started out wet, with mostly cloudy skies and scattered showers and thunderstorms on Sunday. After that the week turned out beautiful with mostly sunny skies and warm, verging on hot, temperatures and moderate breezes. The fishing on Lake Michigan was very good to excellent this week with big catches of big salmon, along with rainbow and lake trout coming into Sturgeon Bay. Most of the action seems to be coming early in the mornings, with that golden hour from one half hour before sunrise to one half hour after producing lots of fish. Anglers fishing early on the bank reef are having excellent success using fly and dodger combinations and a variety of spoons. Later in the day the fish seem to be moving out into deeper water and 50 to 120 feet down. Anglers fishing spoons closer to the surface are connecting with the Rainbows. Baileys Harbor, Rowley’s Bay, Ellison Bay and the Washington Island are all reporting success. Smallmouth bass continue to be caught all over the county however the larger smallies seem to have moved out into deeper water. Perch fishing remains very good with the southern shore of Green Bay, along with Little Sturgeon, Riley’s Bay, and the waters around Chaudoir’s dock producing lots of Perch, along with the weed edges in Sturgeon Bay. The Egg Harbor Marina is also producing some nice catches of perch on small minnows and night crawlers. Crank baits and night crawler harnesses are producing some nice Walleye action from the tops of the reefs. I am still getting reports of walleyes starting to show up in the waters around Chambers and Horse Shoe islands and the shore off of Peninsula state park. The Northern pike action was fair this past week with mostly smaller northerns being taken. Big buck tails are producing a few Muskies from the weed edges in Sturgeon Bay. Little Sturgeon is continuing to produce some nice catches of crappies, bluegills and perch.
Kewaunee County - Rain and storms over the last week have really mixed up the lake. Nicer weather settled in for the weekend however brought many an angler out to the lake. Water temperatures have fallen back in to the upper 40s and have really scattered the fish. Anglers fishing off the pier in Kewaunee have reported that the fishing has been slow over the last week. Casting spoons has limited success this past week, but a few kings have been caught. Anglers fishing off the pier in Algoma have been reporting a few salmon and trout have also been caught using spoons. Anglers that have been trolling out on the lake having been coming in with good catches of kings and rainbows. Anglers have also been catching a few lake trout and a number of cohos as well. Many good catches of fish have been coming in with quite a few limits being taken over the last several days. Most of the fish coming in have been over 15 pounds. Anglers have been fishing any where from 90 to about 300 feet of water. Fish are being caught mostly in depths between 100 and 150 feet, with some fish being caught at 200 feet. Anglers have had the most success using fly and dodger combos, but spoons having also been working as well.
Oshkosh DNR Service Center area
Upper Fox-Wolf basin fisheries report - Walleye fishing in the Fox River has been extremely productive! They are biting on leeches and are running in the 15-16 in. size class. Catfish fishing in the Fox River is also very good. Anglers are catching flatheads, blue and channel catfish using leeches. Walleye action in Lake Winnebago is very good as well. Anglers are having to move around to get bites. Trolling in the mud has been consistent around 4 to 5 miles off shore, though. Some nice walleye and northern action in Lakes Winneconne and Poygan have been reported along with bluegills and perch being hooked in and around the bays.
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SOUTHEAST REGION
Lake Michigan fisheries team report
Sheboygan County - In Sheboygan, shore anglers fishing the piers have been catching a few browns on spoons, but fishing has been slow overall. Trollers off Sheboygan have also had to work hard to find fish. Rainbows and chinooks have been scattered in 80 to 165 feet of water.
Ozaukee County - In Port Washington late morning and early afternoon shore anglers near the power plant have been able to catch an occasional brown on spawn. Trollers out of Port Washington have been catching rainbows, chinooks, and coho in 80 to 100 feet of water. The rainbows and coho have been in the top 20 to 30 feet of water, while the chinooks have been closer to the bottom.
Milwaukee County - In Milwaukee, shore anglers have been catching good numbers of perch off the end of McKinley pier and off the rocks at Bender Park. Most perch are being taken early in the morning on minnows or crab tails. Boaters fishing for perch have been catching good numbers in the Milwaukee harbor around the breakwall and the gaps, as well as off the Oak Creek Power Plant. Milwaukee trollers have been catching chinooks, coho, and rainbows, although in lower numbers than in past weeks. Most fish have been caught in 60 to 70 feet of water off the filtration plant.
Racine County - In Racine, pier anglers have occasionally taken rainbows on spawn sacs. Perch anglers fishing off the rocks at Pershing Park and near the DeKoven Center have been catching good numbers on live minnows and jigs. Boaters looking for perch have taken their limits at the bubbler or off the breakwall. Racine trollers continue to catch mostly coho, but a few chinooks have been taken as well. Spoons or dodger and fly combinations fished between 50 and 100 feet of water have been the most productive.
Kenosha County - Kenosha shore anglers have been catching good numbers of browns on silver or glow spoons in the harbor. Shore anglers looking for perch have been having sporadic action. The most fish have been taken in the early morning hours off the ends of the piers and in Southport Marina. Minnows, crab tails, and jigs have all taken perch. Anglers fishing for perch from boats have been catching good numbers at the bubbler and off the rocks at the water treatment plant. Action for Kenosha trollers has been relatively slow, with boats only bringing in a few chinooks, coho, and steelhead. Dodgers and flies in green, white, or orange have been effective in water less than 50 feet deep.
Inland fisheries team report
Summer patterns have started to develop. Fishing remains very good in the area.
Waukesha County - Bluegill fishing was great on area lakes last week, nice catches of gills were being caught around weeds in 5-15 feet of water. Best baits have been very small jigs tipped with crawlers and waxies. Start looking for fish to suspend as water temps rise. Crappies are being caught suspended above weeds, slip rigs tipped with small minnows have been best. Bass have been active on most area lakes, crawlers, leaches and jigs have been putting slobs in the boat. Musky action has been excellent, surface baits and large jerk baits have been producing action. Best action has come from shallow weed flats and inside weed edges.
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SOUTH CENTRAL REGION
Dodgeville DNR Service Center area
Grant County
Wyalusing State Park - The Mississippi River stage at Prairie du Chien as of June 26 was 7.4, down .01 from the previous day. Many of the spring migrants have moved on. Recent sightings include: robins, nuthatches, red-bellied woodpeckers, downy woodpeckers, red-headed woodpeckers, hairy woodpeckers, yellow-bellied sapsuckers, pileated woodpeckers, cerulean warblers, prothonotary warblers, warbling vireos, yellow-throated vireos, Acadian flycatchers, Kentucky warblers, yellow-throated warbler, Northern orioles, rose-breasted grosbeaks, bluebirds, bald eagles, turkey vultures, and hummingbirds. The number of hummingbirds feeding on feeders at park office has decreased considerably from the past few weeks. This is most likely due to the adults feeding the young. Seems to happen every year about this time. Cerulean and prothonotary warblers, warbling vireos, yellow-throated vireos and orioles can be found at the boat landing in the park. The Acadian flycatcher might be spotted about 300 feet from the boat landing on Sugar Maple Nature Trail. The Kentucky warbler and the yellow-throated warbler have been sighted near the Homestead Picnic Shelter on the southern loop of the Turkey Hollow Trail. The park bluebird monitor volunteer reported on June 15 that 43 bluebirds have fledged so far this year. One late nest had 3 young on June 15. If those 3 fledged, total to date will be 46 fledglings from the first brood. The second brood has begun. On June 15, there were four boxes with eggs, two new nests, and 1onebox with tree swallow eggs. The prairie is beautiful. It is the prettiest it has ever been. Flowers blooming in the park office prairie include: coreopsis, white indigo, beardtongue, pale purple coneflower, black-eyed susan, spiderwort, prairie phlox, butterfly weed, purple prairie clover, St. Johnswort, tall bellflower, and hoary vervain. Butterflies observed include: cabbage white, Milbert’s tortoise shell, red admiral, tiger swallowtail, comma, painted lady, hackberry. Black rat, fox, bull, Eastern hognose, and prairie ringneck snakes have been seen.
Fitchburg DNR Service Center area
Jefferson County - Anglers are still catching some 4-5 pound channel catfish on the Upper Crawfish River near Hubbleton. The fish are biting on night crawlers, chicken livers and stink bait. Evening fishing has been the best time to catch them. Anglers were catching some bluegill on Rock Lake yet. The fish are suspending out in deeper water on the lake and the best success has been by drifting. The fish were biting on spikes, plastic and waxworms. Largemouth bass were biting well on the lake on an assortment of baits including leeches and spinner baits. Many of the bass being caught were just under the legal size limit. A few dead crows and blackbirds are showing up in Jefferson County most likely due to West Nile virus and the growing mosquito population over the past week and a half. Whitetail deer fawns have been moving about more with several getting hit on the roadways in Jefferson County. Motorists have been calling the wardens to obtain a special tag to possess the spotted fawns.
Sauk County - Fishing activity has been good on area lakes. Trout are biting in the 16 to 25 feet range on Devil's Lake with limits being taken. Pheasant chicks are hatching and a number of chicks have been seen in road side ditches. Wardens remind boat users to check over their boats for safety equipment before going out on the water i.e. Life preservers, battery cases, fire extinguishers, boat lights etc.
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WEST CENTRAL REGION
Baldwin DNR Service Center area
St. Croix County
Willow River State Park - Fishing reports include a large bass caught on the lake and a couple of undersized walleye below the dam. A 35-inch northern was caught on the weekend. A rainless cold front blew in Tuesday which may slow the fishing for a day or so. Sunday through Thursday night camping generally has a reasonably good selection of sites to choose from. Weekend camping tends to be full with reservations. This will be a busy weekend for events at the park. Friday, June 29 there will be a Native American storytelling and a campfire behind the Nature Center at 7:30 p.m. Saturday, June 30 at the boat launch picnic area at 7 p.m. will be Flowers, Fairies, and Weed Warriors. This event will have a story and craft work for kids of all ages. The Full Moon Hike starts at 8 p.m. as a separate event at the Nature Center. All of these events are free with vehicle admission. A few people have been continuing cross-country ski training by been pole walking the trails at cooler times of the day. Canoe or kayak paddling is a good cross training for skiing.
La Crosse DNR Service Center area
The young from second clutches of rabbits and squirrels are venturing from their nests. Often times, rabbits and squirrels will give birth to two or three broods each year, with four to six young per brood. Early broods tend to number on the higher side of the range; later broods on the smaller side of the range. Both of these mammals are extremely productive species.
Eau Claire DNR Service Center area
Brunet Island State Park – The open water game fish and pan fish action has been very good this month. Pan fish have been active in the shallows. Smallmouth bass have been hitting below the dams. Largemouth bass and northern pike action has been productive, and there has been good musky action in the area. The painted and snapping turtles have been digging nests throughout the park property. Canada geese goslings are quite numerous this year and are growing quickly. Species of birds we have been seeing or hearing include: indigo buntings, towhees, golden finches, ravens, rose-breasted grosbeaks, loons, robins, red polls, a variety of wrens, phoebes, Canada geese, turkey vultures, northern juncos, piliated woodpeckers, great blue herons, green herons, barred owls, ravens, osprey, bald eagles and belted kingfishers. The whitetail does are having their fawns, and we are seeing quite a few young gray and red squirrels out on their own. The fireflies, mayflies, and monarch butterflies have arrived. Many varieties of dragonflies have shown up in great abundance. Blue flag, dog violet, orange hawkweed, wild columbine, ox eye daisy, wooly yarrow, grove sandwort, blackberry and raspberry vines, and common and wood strawberry are in bloom. The wood strawberries are beginning to produce fruit.
Chippewa Moraine Ice Age State Recreation Area - - Anglers have been having some luck lately with panfish and walleyes being caught in area lakes. Stop at the Interpretive Center for a free lakes book detailing access, type, and lake information. Recent animal and bird sightings include white-tail deer, red fox, woodchucks, and porcupines. Spend a summer day hiking one of the beautiful loop trails, or head out on the linear Ice Age Trail. Along the way you will be treated to a variety of songs from many of our resident and migrating birds. Some of our favorites recently seen include rose-breasted grosbeaks, grey catbirds, eastern kingbirds and ovenbirds. For those more adventurous hikers, a side trip to hike the newly constructed Chippewa River Segment of the Ice Age Trail is a scenic must. Kids are invited to visit the Interpretive Center that offers many hands on activities. They can catch bugs to feed the fish, frog, and turtles, complete an indoor scavenger hunt and earn a Smokey Bear prize, and even hold a snake or turtle and ask the Rangers a bunch of questions.
Wisconsin Rapids DNR Service Center area
Buckhorn State Park – Warmer weather is great for swimming, canoeing and kayaking. There is starting to be algae in the lake. There is a cold water rinse shower in the beach picnic area. Canoes and kayaks are available for renting. Many visitors are using the beach in the park. Mosquito activity is moderate -- remember bug spray! Little brown bats have been returning to the bulletin board by the park office. Check out the new signs on the savanna/pond nature trail. Sign up for a guided canoe/kayak tour Friday, June 29 at 8 am. Saturday, June 30 at the park amphitheater is a concert in the park at 7 p.m. Remember to secure your food when camping -- there are raccoons in the park and a black bear was sighted this past week. Take photos of the wildflowers, wildlife, sunsets, people using the park, etc. for the annual photo contest. 2007 youth deer hunt applications are now available. Deadline is July 15.
Roche-A-Cri State Park - Enjoy a great hike up the stairway to the top of the Roche-A-Cri Mound. Deer and turkeys are abundant in the park. Deer fawns and turkey poults have been sighted throughout the park. Many summer wildflowers are in bloom in the woodlands and prairies, including the beautiful Butterfly Milkweed. Take a hike through the prairie to try and catch a glimpse of the endangered Karner Blue Butterfly. The campground has had many available campsites during the week, along with a couple available campsites on the weekends. The 2007 photo contest is well underway - remember your camera to catch great springtime photos for the contest.
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VHS update as of June 28, 2007
Test results
All test results returned this week came back negative for VHS. A total of 121 samples of wild fish have been sent in for testing since 2006 and as of June 27, 93 samples had tested negative for VHS, results are still pending for 28 samples, and six samples have tested positive for VHS: freshwater drum from Little Lake Butte des Morts and from two locations in Lake Winnebago; smallmouth bass from Sturgeon Bay, brown trout from Lake Michigan near Algoma and Kewanee, and whitefish from northern Green Bay.
Testing and fish kills are both expected to slow in coming weeks because fish immune systems are stronger with warmer water temperatures and better able to withstand the virus. Although such infected fish continue to carry VHS, the resulting low viral loads in fish are more difficult to detect, leading to false negatives. Each VHS test cost $500 and takes 28 days to complete. DNR will suspend planned surveillance testing to assess where the virus is until water temperatures cool to 60 degrees Fahrenheit but will continue to test fish that look diseased and those killed in large numbers. Updated test results are available on the DNR Web site at [http://dnr.wi.gov/fish/documents/vhs_widistribution.pdf].
VHS prevention rules slated for public hearings this summer
Public hearings have been approved for later this summer on proposals to make permanent existing VHS rules. The state Natural Resources Board unanimously voted to authorize public hearings for the proposals during its June 27 meeting in Oconomowoc. The existing VHS emergency rules aim to stop the movement of live fish, fish eggs, fish parts and water away from waters where the disease has been found or is suspected: Lake Michigan, Lake Superior, the Lake Winnebago System, the Mississippi River and their tributaries up to the first dam or first barrier impassable to fish. The emergency rules also automatically extend the requirements statewide if a fish from outside those waters tests positive for VHS. And they establish a permit system for people who harvest and sell bait from the wild to help DNR track potential VHS sources.
Boater and angler compliance
Tournament organizers and fishing clubs are stepping up to the plate to assure that VHS is not accidentally spread. Mike Donofrio, DNR fisheries supervisor stationed in Peshtigo, met with organizers and participants at the Green Bay Masters Walleye Circuit tournament on June 20 and 22 before the event started on efforts to prevent the spread of VHS through tournament activities and to increase the survival of walleye released. “At the weigh-in events, organizers set up recovery tanks as I requested. The fish were released through a 6-inch PVC pipe about 40 feet long with a garden hose in it. We asked the fishermen not to exchange water in live wells once in the river and bring ice with them to moderate temperatures all day. The organizers paid for ice each day to keep water cooler in the recovery tanks -- about 50 bags per day. They also had the tanks on constant exchange with river water and oxygenated. Also, Dan Farah of Walleyes for Tomorrow organized volunteers to assist in the live release of walleye and distribute spray bottles with chlorine solution at the boat landing each day,” Donofrio reports. The tournament attracted 184 boats and had a top prize of $27,000.
Bob Korth, who directs the UW-Extension Lakes program, reports that VHS has been a hot topic and he has been giving several presentations a week to lake groups, including a recent update at the Northwest Wisconsin Lakes Conference, June 22 in Cable. Bayfield County Lakes Forum partnered with the Bayfield County delegation of the Wisconsin Conservation Congress earlier this month to host a VHS workshop in Ashland to help explain the disease, why it’s a threat to northern Wisconsin, and how to prevent its spread. Lakes Forum president Jim Bakken presented information, DNR Warden Jill Schartner explained the emergency rules regarding fishing and boating in Lakes Superior and Michigan and the Lake Winnebago system, and Scott Toshner, DNR’s Bayfield County fisheries biologist, presented information as well as Stefania Strzalkowska, Bayfield County aquatic invasive species coordinator.
Most frequently asked question of the week
What can provoke a VHS outbreak, and why do some VHS-infected fish die while others don’t?
Water temperature and stress can influence the severity of a VHS outbreak. The much-documented European strain of the virus grows best in fish when water temperatures are 37-54 degrees Fahrenheit and most infected fish will die when water temperatures are between 37- 41 degrees. Biologists do not yet know the temperature ranges for the new strain of VHS, which was first detected in eastern Great Lakes fish in 2005 and this spring in Lake Winnebago, Lake Michigan, and Green Bay; there are some indications this strain can replicate in fish at higher water temperatures. Stressors, including poor water quality or lack of food, release the stress hormone, cortisol, which suppresses the fish immune system. Additionally, other hormones related to spawning can also suppress the immune system. This may be why so many of the fish kills in the Great Lakes have occurred just before, during, or right after the spawning period. Once a fish has produced VHS antibodies, it will be protected from future infection by the virus for some time. This means that after the first disease outbreak occurs in a lake, the older, surviving fish will be protected. Younger fish will not have antibodies to the virus, so they will likely die at a higher rate when the next disease outbreak occurs.
Last Revised: Thursday June 28 2007
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