Wednesday, January 10, 2018

Attention Winnebago System Sturgeon Spearing Enthusiasts:

WCSFO Photo by: John Durben

The 2018 sturgeon spearing season on Lake Winnebago and the Upriver Lakes is only a little over a month away, starting on Saturday February 10.  We've experienced some very cold weather the last few weeks and have some pretty thick ice developed throughout the system.  In fact, some of the local fishing clubs and conservation groups have already put out their tree lines and are now maintaining access points and plowed roads.  From what I've heard, Lake Winnebago is pretty rough though and there are quite a few cracks, so be sure to use caution and remember no ice is every 100% safe.

Many spearers are starting to wonder about water clarity so we had one of our technicians check clarity in a couple of locations today (January 8).  Attached is a map of where he checked clarity and what visibility was.  In the locations checked, clarity ranged from 7.5-10.5' with quite a bit of variability.  This is a very small sample size, but it appears that clarity is not great at this point in time.  Hopefully things will improve a bit over the next month.  We will be checking clarity again during the week leading up to the season and I will be sure to send out that update once it becomes available.

I also have attached a copy of the spearing rules and regulations for the 2018 season.  I hope everyone had a happy holiday season and I look forward to the month of anticipation that lies ahead between now and February 10!
  
Ryan Koenigs
Senior Fisheries Biologist / Winnebago System Sturgeon Biologist
Wisconsin Department of Natural Resources
625 E County Rd. Y, Suite 700
Oshkosh, WI 54901
Phone: (920)303-5450
Fax: (920)424-4404

Thursday, December 21, 2017

Wisconsin Outdoor Report December 21, 2017

Snow is piling up on properties in northern Wisconsin, but has been melting away in southern counties. The Brule River State Forest is grooming cross-country ski trails after an additional 2-3 inches of snow brought their total to around 10 inches. The Northern Highland-American Legion State Forest is also packing trails for skiers but still has not been able to set tracks. Trails have also been groomed at Newport, Peninsula and Potawatomi state parks in Door County but most of the southern half of the state has no snow cover. A couple more northern counties have opened or partially opened snowmobile trails but conditions are only fair to poor on the Wisconsin Department of Tourism's Snow Conditions Report (exit DNR).

In the north, many smaller lakes have 4 to 6 inches of ice, but some of the larger lakes just froze up completely in the last week and have only 1 to 4 inches of ice. There is a fair amount of snow on the ice which is leading to slush and inconsistent ice underneath. People should be very careful if they venture out to fish. Anglers finding good ice were catching bluegills in shallow green weeds and crappies a little deeper over flats or near cribs. Walleye anglers are catching walleyes on small minnows set under tip ups on the outside edges of weed beds. Pike action on tip ups has been slower than average.
Southern areas that had been forecast to get several inches of snow this week, will likely now only see a dusting. This means easy access for those looking to get out on a hike this coming week. The last firearm deer hunt is just around the corner in the Farmland Zone--the Holiday hunt runs from Dec. 24-Jan. 1 and is an antlerless only hunt. One last reminder for pheasant hunters: the state game farm will be releasing an additional 1,500 birds on five wildlife areas prior to the holidays for some late season hunting.
There are many mammals moving around, with tracks of grey wolves, fisher, coyotes, and even a black bear were seen around Crex Meadows State Wildlife Area.
Rough-legged hawks have been observed recently in the valleys of Crawford and Vernon counties stocking up on rodents before the coming freeze. These large raptors get their name from their furry-looking legs, which are thoroughly covered to the toes with soft feathers. They breed in the Arctic tundra, but winter primarily in the lower 48 states, where they hunt small mammals on open fields.
Eagles are starting to move in to the Prairie du Sac area and can frequently be seen hunting the Wisconsin River. Other migrants have been seen along the Lake Michigan shoreline in Milwaukee, with scaup, goldeneye, mergansers and even a handful of scoters, long-tailed ducks and harlequin ducks being seen on occasion. The snowy owl count continues to sit at 173 across 57 of Wisconsin's 72 counties as of December 13.
Amnicon Falls will host a New Year Eve candlelight hike with candles leading up to the histoic Horton bride offer views of thee waterfalls. - Photo credit: DNR
Amnicon Falls will host a New Year Eve candlelight hike with candles leading up to the histoic Horton bride offer views of thee waterfalls.Photo credit: DNR Kevin Feind
Ring in the New Year with a New Year's Eve candlelight hike at Amnicon Falls State Park and then start the New Year off on the right foot by taking part in any of 17 First Day Hikes that will be held at Wisconsin State Park System properties across the state. And get ready for other candlelight events that will begin the first weekend in January with more than 35 events running through early March.
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Northern Region

Superior DNR Service Center area
A snowy scene along the Brule River. - Photo credit: DNR
A snowy scene along the Brule River.Photo credit: DNR
Brule River State Forest - Happy Winter Solstice! The calendar says Dec. 21 is the first day of winter, but it has looked like winter here for a while now. The area received an additional 2-3 inches of snow the night of Dec. 20, bringing the total on the ground to about 10 inches. The After Hours cross-country ski trails are open and being groomed after this new snowfall. Conditions are good. Trail conditions are kept up to date on skinnyski.com and norwiski.com. Last week temperatures were above freezing, but the temperatures for the weekend are going to be frigid. On Christmas Day, the high temperature is forecast to be at or just below zero. It will definitely be a white Christmas in the Brule River Valley this year. - Diane Gobin, visitor services associate
Pattison State Park - The Pattison State Park Ski Trail was groomed Dec. 20 but track for classic skiing was not laid due to lacking a consistent smooth base. There will be a candlelight hike at Amnicon Falls State Park on New Year's Eve from 4-8 p.m. It is a free event, but a vehicle admission sticker is required. The Friends of Pattison and Amnicon Falls State Parks will be having hot cocoa, cider, and s'mores to enjoy. - Kevin Feind, property supervisor
Hayward DNR Service Center area
Sawyer County - Most smaller lakes have 4 to 6 inches of good ice, but some of the larger lakes just froze up completely in the last week and have 1 to 4 inches of ice. There is a fair amount of snow on the ice which is leading to slush and inconsistent ice underneath. People should be very careful if they venture out to fish. Anglers finding good ice have found the fishing good. Bluegill were biting well both in shallow green weeds (5-10 feet of water) and off of deeper cribs. Walleye are taking minnows on tip-ups on the outside edges of weed beds in 10 to 20 feet of water. Pike action on tip ups has been slower than average, but that might point to good pike fishing in the near future. Pike never seem to stay inactive for long in the winter and can typically be caught in 5-15 feet of water, particularly where there are weeds. - Max Wolter, fisheries biologist, Hayward
Spooner DNR Service Center area
Crex Meadows State Wildlife - Birds are very scarce now in the Grantsburg Area. Recent cold weather and snow have forced most of the remaining migrants out of the area, leaving only the winter inhabitants. There were still a few water birds around this week, including Canada geese, trumpeter swans, mallards, and an American wigeon. Highlights this week were the snowy owls (one spotted on Main Dike Road), red crossbills, and common redpolls. A few large groups of common ravens and wild turkeys were seen over the weekend, as well as a large group of rock pigeons. There were many mammals moving around within the last week as well. Tracks of grey wolves, fisher, coyotes, and even a black bear were seen around Crex Meadows. - Lauren Finch, wildlife educator
Park Falls DNR Service Center area
Price County - Ice development is coming along very slowly on area lakes. Some lakes have 4-6 inches of ice while others have less than 1 inch in spots. Last week's cold spell did not put on as much ice as anticipated. This week's snowfall will insulate the ice and slow any development that is taking place. Extreme caution should be used when venturing out onto the ice. Anglers that have been getting out in the Park Falls area are catching fish. Bluegills are biting in 4-7 feet of water on small jigs with spikes. Crappies are being found a little deeper over flats or near cribs. Minnows with slip bobbers are working well for them. Walleye anglers are catching walleyes in 3 to 6 feet of water on small minnows set under tip ups. Every day has been different as far as action. Somedays they are biting well, somedays they have been very picky. It has been dependent on the weather fronts pushing through. - Chad Leanna, fisheries technician, Park Falls
Flambeau River State Forest - The Flambeau Hills Cross Country Ski Trail has been packed several times in preparation for setting track. There is a base setting up and the snow in the forecast and the cold temperatures will certainly add to that base. The trail is open for skate skiing. Weather pending, the trail will be packed again on Saturday Dec. 23 and groomed the first week of the new year. The snowmobile trail has been groomed and is in use. Hiking trails are open throughout the Forest. As the snow depth mounts, you may only have access with snowshoes. The snow depth is about 7 inches with more in the forecast. Dabbles of ice are flowing down the Flambeau river and the Lake of the Pines and Connors Lake have about 3 inches of ice and a little more along the edges. This Wisconsin winter is going to be a shock for the 30 Kentucky elk and calves released July 6 in the forest. They were originally trapped in 40, 50, and 60 degree Kentucky January weather. However, they're "hard wired" and adapted for the cold. The originator elk for the Kentucky herd came from out west, where subzero cold and blowing snow is common place. Though many of these imports have had it easy they do have the "equipment" to adapt. An elk's winter coat has even greater insulation than a white-tail's winter coat. There are eight timber sales occurring throughout the forest. There will be more starting after the New Year. The weather forecast for the weekend indicates Friday will be mostly cloudy, with a high of 26 and low of 7. Saturday, mostly sunny with a high of 12 and a low of 2. Sunday is forecasted to be mostly cloudy with a chance of snow and a high of 12 and low of -8. Christmas Day will be partly sunny and cold, with a high near -2 and a low of -13. Lake of the Pines Campground and Connors Lake Campground are closed for the season. - Diane Stowell, forestry technician advanced and visitor services associate
Woodruff DNR Service Center area
Oneida County - Anglers have been on the ice for the last couple weeks. Some early reports are that some folks are catching walleyes of decent size. Ice conditions are still variable up here. It's been cold, in the teens, but the amount of steady snow we've had hasn't been the best for making good ice. People are reporting anywhere from 2-8 inches or so depending on lake (smaller lakes tending to have more); however, anybody going out should still exercise caution. - Hadley Boehm, fisheries biologist, Woodruff
Northern Highland-American Legion State Forest - Cross-country ski trails were groomed Dec. 19. All trails have been packed with the groomer but track has not been set. McNaughton has no bare spots but a wet area on the Red/Skaters loop just after leaving the trailhead. Escanaba and Madeline trails have all loops packed with the groomer. Raven Trail is packed with no bare spots but still thin under the conifers on the Red loop by "Hemlock hill" and by Hemlock lake. - Tony Martinez, parks and recreation specialist
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Northeast Region

Peshtigo DNR Service Center area
Marinette County - About 8-10 inches of snow fell late last week. Warm weather followed and reduced the depth to about 6 inches. More snow is predicted for this week. Some snowmobile trails have been groomed, but remain closed. Ice fisherman have been testing the ice on area lakes. Ice conditions are poor on a number of area lakes with only a couple of inches of ice covered by slush and snow. Some fisherman have reported 5 inches of ice on portions of Lake Noquebay. No permanent shacks have been seen on lakes just yet. The last rifle hunt is just around the corner for the Farmland Zone of the county--the Holiday hunt runs from Dec. 24-Jan. 1 and is an antlerless only hunt. All hunters are reminded to wear blaze orange/pink. Snowy owls have been spotted in southern portions of the county near the Peshtigo River and the bay of Green Bay. - Aaron McCullough, wildlife technician, Wausaukee
Sturgeon Bay DNR Service Center area
Newport State Park - There is about 8 inches of new snow. Trails have been groomed for cross country and skate skiing. We ask hikers and those with snow shoes to please stay off of the tracks. More snow is in the forecast for next week, so conditions could change rapidly. - Beth Bartoli, naturalist
Peninsula State Park - The Blue, Purple, Orange, Red and Yellow cross-country ski trails have been groomed and are in good condition. There are some bare spots and the hills on the Purple Loop are more poor than good due to the rocks. There are small bare spots in the more heavily wooded areas. Reminder: Hiking, snowshoeing, fat tire bikes and pets are not allowed on snow covered ski trails. The sledding hill is currently closed; when it opens only tubes and plastic sleds can be used on the sledding hill. - Jessica Doell, visitor services associate
Potawatomi State Park - The park received about 10 inches of snow on Dec. 13. All ski trails have been tracked. Classic trails are in fair condition since the warm temperatures have caused the tracks to sink to the base of trail in a few spots. The skate skiing trails are in good condition. More snow predicted later this week will improve trails now that there is a base. Please remember that hiking, biking, and pets are not permitted on ski trails when snow-covered. Please see the Potawatomi winter use map [PDF] for trails open to winter hiking and snowshoeing. Bikes may be ridden on park roadways. - Jaclyn Moeri, visitor services associate
Wautoma DNR Service Center area
Waupaca County - Deer have been getting very active during daylight hours. Should be a good opportunity for those who chose to hunt during the holiday hunt. Almost all area lakes iced over, a few people out fishing - have no report on their success. We only had a couple inches of snow on the ground and it got to 40 degrees today. One can only assume there are no trails open. - Karl Kramer, wildlife technician, Wautoma
Waushara County - The area was looking forward to getting some decent snow for Christmas, but now it looks like we will just receive a nice light covering to whiten things back up. That means that the Ice Age Trail will be pretty easy to access for some hiking and other state lands for the upcoming Holiday Hunt. Be prepared to bundle up though as later this weekend the temperatures are about to plummet. Make sure to have some extra layers and be careful when venturing out, the temperatures being forecasted are enough to cause frostbite and hypothermia if out in the cold for too long and not prepared for it. Remember to make a plan and stick to that plan and always let someone know when you plan to be back and where you plan to go! The ice has done OK in the warmup, but still is nowhere near completely safe (as no ice ever is), but the cold will be making more ice every day and ice fishing has been pretty decent as of late. Take care and have a great Holiday. Use this time to get out and enjoy the frigid temps with family! - Ben Mott, conservation warden, Wautoma
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Southeast Region

Milwaukee DNR Service Center area
Milwaukee County - With the warm winter weather, most of our waterways are currently free of ice. However, we should see cold and snow over Christmas weekend, with more ice cover on our inland lakes and ponds. Our winter migrants are in Milwaukee again, with an abundance of scaup, goldeneye and mergansers, and even a handful of scoters, long-tailed ducks and harlequin ducks being seen on occasion. As of Dec. 13, an estimated 173 Snowy Owls have been tallied across 57 of Wisconsin's 72 counties. Check out the map of recent sightings here. This total puts us on track for one of the largest irruptions in recent years. Visit the snowy owl page at the DNR website for more information. There are antlerless deer bonus carcass tags available for purchase across the state, including in Milwaukee County, and now is the time to take advantage of our archery deer season, which runs through Jan. 31 within our metro subunits and Jan. 8 in the rest of the state. If you already harvested an antlerless deer, you can visit the DNR website to see where in the state additional antlerless carcass tags are available. You can also visit the department website for updated deer harvest information across the state. - Dianne Robinson, wildlife biologist, Milwaukee
Kettle Moraine State Forest, Lapham Peak Unit - The man-made ski trail was groomed Dec. 19 and was in good shape after the grooming. Warm temps will soften the trail as the day goes on. Lights will be on until 9 p.m. Monday through Saturday. Please no hiking on any of the man-made snow, the most damage from hikers occurs with soft snow. - Jay Abts, ranger
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South Central Region

Fitchburg DNR Service Center area
Columbia County - Snow enthusiasts are still impatiently waiting to get out and enjoy the outdoors. What little snow we had on the ground has mostly melted away in the past few days. Most waterbodies have some level of ice on them and some brave souls have ventured out at Whalen's Grade at Lake Wisconsin and other early ice areas. With the warm temps, animals like raccoons and skunks have been active and moving around more than normal for this time of year. Eagles are starting to move in to the Prairie du Sac area and can frequently be seen hunting the Wisconsin River. Hundreds of cranes were staging in Lewiston and Newport townships at the end of last week and will likely stick around for a bit yet. Hunters at the Mud Lake Wildlife Area between Rio and Poynette are in for a holiday treat - a last 'stocking' of pheasants will occur just before the holidays. Enjoy the rest of the pheasant season! - Sara Kehrli, wildlife biologist, Poynette
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West Central Region

La Crosse DNR Service Center area
Vernon County - Rough-legged hawks are being observed repeatedly in the area. These large buteos breed in the Arctic tundra and migrate to and winter primarily in the lower 48 states. They feed mainly on small rodents and often hunt for them by facing into the wind and hovering above a grassy field before diving down on the unsuspecting prey. Deep snow cover tends to push the birds farther south. Rough-legged hawks get their name from their furry-looking legs, which are thoroughly covered to the toes with soft feathers. The ferruginous hawk and golden eagle are the only other American raptors that have legs feathered all the way to the toes. For a raptor, rough-legged hawks have relatively small feet and bills. In flight, rough-legged hawks display long, rounded wings, smooth, shallow wingbeats, primary feathers with very pale undersides, and square, dark wrists or carpal patches. These strikingly beautiful birds are often encountered on the open ridgetops or wide valleys in Crawford and Vernon counties. - Dave Matheys, wildlife biologist, Viroqua
Eau Claire DNR Service Center area
Lake Wissota State Park - Species of birds seen or heard include: ravens, black capped chickadees, phoebes, northern juncos, pileated woodpeckers, barred owls and bald eagles. The campground is closed for the winter season. Ice anglers should be thinking about 'gearing up' as first ice has formed in the bays adjacent to the park. Cross country skiers are anxiously waiting additional snowfall as there has not been enough to groom the trails yet.- Dave Hladilek, park manager
Wisconsin Rapids DNR Service Center area
Buckhorn State Park - The trail into the new campground is open for dog walking and is packed when there is enough snow. Mark your calendar for the First Day Hike from 1-3 p.m. on Jan. 1. Meet at the South shelter parking lot to hike or snowshoe. Hot chocolate and cookies after the hike! Bow hunting is happening in the park and wildlife areas until Jan. 7. There is no holiday hunt in the surrounding area. Pets are not allowed on the ski trails when they are groomed. - Heather Wolf, park manager

Roche-A-Cri State Park - The stairway is not maintained in winter and can be icy; it is open from 6 a.m. to sunset. . Bow hunting continues to Jan. 7. All other hunting/trapping is now closed. - Heather Wolf, park manager

Thursday, December 14, 2017

Wisconsin Walleye Initiative funding boosts state and private production

MADISON - A record 881,977 walleye were stocked in key Wisconsin waters this past year as state, private and tribal hatcheries continued to put Wisconsin Walleye Initiative funding to work for anglers, state fisheries officials said.

"We're very pleased that the investment made to hatcheries through the Wisconsin Walleye Initiative and the hard work of our fisheries crews and our partners are once again paying off for Wisconsin anglers," says Justine Hasz, fisheries director for the Department of Natural Resources.
State fish crews collecting extended growth walleye from the Art Oehmcke State Fish Hatchery near Woodruff. - Photo Credit: DNR
State fish crews collecting extended growth walleye from the Art Oehmcke State Fish Hatchery near Woodruff.
Photo Credit: DNR
The initiative, proposed by Gov. Scott Walker with the 2013-15 biennium budget and approved for continuation through the 2017-19 budget, has paid to upgrade state hatcheries and provided extra operating funds needed to keep fish on site longer and feed them minnows. The initiative also provided grants to upgrade three tribal hatcheries and six private facilities to meet the stocking demand statewide.
"We stocked a record number of fish again, meeting the need identified by fisheries biologists and we're poised to meet the needs long into the future for walleye stocking using public and private partnerships," says Dave Giehtbrock, DNR fisheries culture section chief.
Natural reproduction accounts for more than 80 percent of the walleye caught in Wisconsin. The Wisconsin Walleye Initiative is part of DNR's overall management strategy to help restore naturally reproducing populations of walleye in lakes that formerly supported naturally reproducing populations and improve walleye numbers in lakes that need regular stocking to maintain good fisheries.
While stocking the larger, extended growth fingerlings makes sense in some lakes, DNR also stocks about 1.4 million small fingerlings each year, and works with several cooperators to stock walleye fry into several bodies of water. DNR fisheries biologists develop stocking plans for the different sized fish based on specific lake conditions; in some lakes the smaller fish perform very well and are more cost effective than the larger fish.
In the last year before the launch of the Wisconsin Walleye Initiative, DNR stocked 142,121 extended growth walleye. Since the initiative began, DNR has stocked 455,307 large fingerlings in 2013, 719,670 fish in 2014, 760,969 fish stocked in 133 waters in 2015 and 797,815 in 2016.
Those totals include the contributions from tribal and private hatcheries. In 2017, 177,891 fish came from private and tribal hatcheries.
Walleye are a favorite quarry for Wisconsin anglers and boost the economy by driving expenditures for lodging, dining, retail purchases, guided trips and tournament participation among other things. Wisconsin remains one of the top three fishing destinations in the U.S. with resident and nonresident anglers generating an economic impact of nearly $2.3 billion per year, according to the American Sportfishing Association.
To learn more, visit the DNR website, dnr.wi.gov, and search "Wisconsin Walleye Initiative."

Monday, August 14, 2017

Conservation Wardens Need Your Help!

Assembly Bill 411 Seriously Undermines Fish and Game Enforcement

Assembly Bill 411 threatens the ability of Conservation Wardens to effectively enforce hunting, fishing and trapping regulations on the 80% of Wisconsin that is privately owned.

Under current law any law enforcement officer including conservation wardens has the authority to enter open fields of private land to assure compliance with laws. They do not have authority to enter buildings or areas near buildings.

Wardens need the authority to enter open fields to assure that individuals hunting, fishing or trapping have the appropriate licenses and stamps to hunt, fish or trap and to assure that individuals on private land are complying with all hunting, fishing and trapping regulations.

Fish and wildlife are owned by the public and unless conservation wardens are allowed to go onto the open fields of private land to enforce hunting, fishing and trapping regulations, fish and game on that property from a practical standpoint becomes private.

There should be the same fish and game regulation enforcement on private lands as public lands.

Support your local Conservation Warden

Ask your State Senator and State Representative to Vote NO on Assembly Bill 411.

Go to the legislative website first page to find out how to contact your legislators: www.legis.wisconsin.gov


Source: Wisconsin Wildlife Federation’s - Wisconservation

Monday, July 17, 2017

Tiny Quagga Mussels Have Big Impact on Lake Michigan . . . And Perhaps Climate Change

July 17, 2017

By Marie Zhuikov

As prior researchers have demonstrated, Wisconsin Sea Grant researchers further confirm that the tiny quagga mussel has an outsize impact on Lake Michigan. What’s novel about the study team’s work is the exploration of the age-old biological truth: what goes in must come out. They found the invasive mussels’ sheer numbers and feeding efficiency are changing the lake’s ecosystem dynamics. Perhaps the climate, as well.

Laodong Guo and his graduate student Stephen DeVilbiss, researchers at the University of Wisconsin-Milwaukee, looked at the impacts of quagga mussels from an aquatic chemist’s point of view in a paper published this year in the Journal of Great Lakes Research. They took measurements in Lake Michigan and collected mussels from the lake. They brought the mussels into the lab to assess filtration and excretion rates, and the type of things excreted to better understand their role in the lake’s carbon cycle.

The researchers found that the mussels are highly efficient; each one can filter up to 578 gallons of water every year, with younger, smaller mussels pumping more efficiently. In addition to feces, the mussels excrete dissolved nitrogen and phosphorus, and they “breathe” out carbon dioxide into the water -- so much carbon dioxide, in fact, that it could impact the climate.

“There are so many mussels that the carbon dioxide they release into the water, which gets into the air, may add to the problem of global warming,” Guo said. “Normally, in places like the ocean environment, the water absorbs carbon dioxide. However, Lake Michigan is somewhat oversaturated with carbon dioxide because of the quagga mussels. We need to look at whether this is causing acidification in the lake.”

Estimates of the number of quagga mussels in Lake Michigan by NOAA researchers range from 750 to 950 trillion. More information about how quagga mussels are impacting carbon dioxide dynamics in Lake Michigan and other Great Lakes can be found in a paper Guo and his postdoc, Peng Lin, published last year in Nature’s Scientific Reports.

Another impact the researchers found from their field studies is that quagga mussels are changing the way phosphorous is cycled in the lake. Normally, the amount of phosphorous, a vital nutrient needed for diatoms and other species important in the food web, rises during the winter when it is released from particulate matter resuspended from coastal sediment during storm events and turbulence. The sediment then gets transported from shallow areas to deeper regions in the lake.

“Because quagga mussels carpet the bottom of the lake, the resuspension of phosphorus during winter and during storms is less than it used to be,” Guo said. “When we compare data from
before and after the invasion of the quagga mussels, we find there’s only about one third to less than half of the amount of total phosphorus present in the winter water column.”

Guo thinks these findings will be useful for fishery and environmental managers and Great Lakes researchers. He plans further investigations into how the mussels are impacting the lake’s nutrient and carbon cycling. “It’s kind of unbelievable how the vast numbers of tiny quagga mussels are changing Lake Michigan,” Guo said.

Friday, July 14, 2017

Stalking a Fish Virus

Wisconsin Sea Grant research team tracks the location of the deadly viral hemorrhagic septicemia virus.

July 14, 2017

By Aaron R. Conklin

First, they developed the test. Now they’re using it to track a stealthy, fish-killing virus.

In 2013, Tony Goldberg, a UW-Madison professor of epidemiology, and Kathy Toohey-Kurth, a virologist at the Wisconsin Veterinary Diagnostic Laboratory, used funding from Wisconsin Sea Grant to lead a team that created a quick and accurate test for viral hemorrhagic septicemia virus (VHSV), a deadly disease that attacks the internal organs of fish, leading to bloody and large-scale fish kills. Over the past year—again with support from Wisconsin Sea Grant--Goldberg and his research team have ventured into the rivers and streams of Wisconsin, from the Apostle Islands to Janesville and the Wisconsin-Illinois border, working with the Wisconsin Department of Natural Resources to collecting fish samples to test and track the virus’s current locations and movement among fish populations.

The goal? Developing an effective management strategy to contain VHSV.

“If we catch wildlife diseases early, there’s a lot we can do about them,” said Goldberg. “There’s a window where you can intervene and be adaptive and smart and prevent or even get rid of some diseases with really careful management. VHSV will not be the last fish disease to plague Wisconsin. If we do this exercise and are effective with it, we have a test case, an action plan for the future.”

Taking steps toward that plan has involved a substantial amount of fish sampling and laboratory work. Last fall, Goldberg’s team collected samples from several thousand fish across most of Wisconsin’s major geologic zones.  Whitney Thiel, a graduate student in UW-Madison’s freshwater and marine sciences program, has spent the intervening months performing enzyme-linked immunosorbent assay (ELISA) tests on the scores of fish samples, generating data on the fishes’ antibody levels, which rise in response to an exposure to diseases like VHSV.

The data will help the team solve the project’s biggest mystery—finding the specific cutoff point between negative (never exposed to VHSV) and positive (exposed to VHSV) fish.

“This test has never been applied to many of these fish species before,” explained Goldberg.  “Once we’re able to say what proportion of fish in a lake are serologically positive or negative, that will tell us where in Wisconsin fish have an immunity to the virus.”

That’s critically important information to have, particularly for fisheries managers. VHSV is particularly insidious. Past research (including Goldberg’s) indicates that it can lie dormant in fish population for years, a lurking threat in the absence of visible fish kills. Goldberg studied freshwater drum in Lake Winnebago, using the test his team developed to discover that the fish were maintaining the virus at low levels.

“We know from experience that if you have a na├»ve population and expose them to the virus for the first time, it’s bad--you get fish kills,” explained Goldberg.  “If we have areas where there are a lot of positive fish, we would want to make sure we didn’t move fish out of there into other areas. If we know our fish hatcheries are free of the virus, we might want to stock fish preferentially into lakes that don’t have the virus so they don’t all die and we don’t waste our money.”

Researchers still don’t know how VHSV manages to persist within lakes. Several possible explanations exist, including the fish shedding the virus during spawning. One of Goldberg’s colleagues at Michigan State University, Mohamed Faisal, recently conducted a study that suggested the virus may be associated with Diporeia, the microscopic Great Lakes zooplankton that historically served as a primary food source for multiple fish species.

“We have a virus that wasn’t here before, and it’s pretty clear it kills fish,” Goldberg said. “So what do you do about it? You have to know where it is. If we just close our eyes and choose not to know where the virus is, it’s just going to spread. We need to set management zones, we need to know which fish to move, we need to educate the public.”

Thiel still has several more months of sample testing to complete before a clearer picture of VHSV in Wisconsin can emerge. In the coming weeks, the research will be taking samples from infected fish to  better understand how their immune systems respond to it.


“Honestly, at this early stage, I would not be surprised by any result,” said Goldberg of the ongoing study. “The only thing I’m pretty confident in is that we’re going to find positive fish where we have found them before.”