What do Walleye really See

14 TWINE LINE

2016 SUMMER EDITION

Watching Fish See

New Ohio Sea Grant research aims to improve Lake Erie’s walleye fishery

by Christina Dierkes, Ohio Sea Grant Communications

No matter how useful it will eventually be, sometimes science just looks silly. In Dr. Suzanne Gray’s lab at The Ohio State University, a fish in a cylindrical tank slowly swims in circles as it follows the black and white panel rotating around the outside of the glass. Gray and her Ohio State collaborators, Dr. Jeremy Bruskotter and Eugene Braig, are studying how well fish can see both prey and predators underwater, and how that ability is influenced by changes in water clarity. They hope that the research will help Lake Erie fisheries adapt to algal blooms that reduce underwater visibility, which is important to visual hunters such as Walleye. Those important sport fish, along with prey fish like Emerald Shiners, are the current focus of the project. “We wanted to integrate this really basic science – visual physiology – with the people who are out there catching the fish,” Gray said. “Walleye fishing in Ohio is close to a $1.8 billion industry, and Walleye are going to be influenced in some way by changes to the visual environment that happen with the algal blooms in the late summer and fall.” PhD student Chelsey Nieman already completed a pilot study for the project at Stone Lab, working out details like setting up tanks for various experiments and taking care of the fish used in the study. Her two months at the lab were funded by Ohio Sea Grant’s Small Grants Program, which provides up to $10,000 in research support to applicants. “Chelsey will be the first graduate student working on this project,” Gray said. “She actually has a Master’s degree that is interdisciplinary, so it included fisheries, but also incorporated a social science component. So she’s really excited about using her expertise for the citizen science work on this project as well.” That work will focus on Lake Erie charter boat captains who regularly take clients out to fish for the species of interest to the project.

Lake Erie WalleyeThe researchers will use surveys and interviews to draw on the captains’ expertise in selecting lures, based on years of fishing experience, and test those lures in the lab setting to provide science-based data for anecdotal knowledge of what lures work best for which fish under varying conditions. “Our goal is to create a citizen science project associated with fishing success, with different colors or types of lures, under different turbidity conditions,” Gray explained. “We’ve had a positive response from the fishermen, who want to do anything they can to understand the fishery better. Which makes sense; it’s their livelihood and these blooms are potentially harmful to their business.” The project also received letters of support from the Ohio Department of Natural Resources’ Sandusky Fisheries Research Unit, which helps manage Fisheries in Lake Erie, and Ohio Sea Grant Extension, which educates the public about sustainable local fisheries.

Tracking Lake Erie Walleye

As Chris Vandergoot lowered a portable receiver into the water above one of western Lake Erie’s many reefs, he listened intently through his headphones as the sophisticated electronics searched the depths for that reassuring tone.

It comes quickly. That distinct “ping, ping, ping” is the sound of success.

“It’s wow, they’re back,” Vandergoot said this week, repeating his reaction when some of the walleyes he had surgically implanted acoustic transmitters in months or years earlier, had returned to the reef.

What we know about the greatest treasure trove of walleyes in the world that make Lake Erie home, is that we actually don’t know a whole lot about them. But Vandergoot, and a multinational lineup of biologists from Ohio, Michigan, Pennsylvania, New York, and Ontario are working to change that, armed with some clever pieces of technology.

Fish are captured at various sites, usually through electrofishing, and anesthetized while a quick surgical procedure inserts an acoustic transmitter into their belly area. A few sutures close the opening, some Betadine is applied to the area to ward off infection, and after a short recovery period the fish is back in the water and ready to transmit data and start shedding some light on its travels, its habitat preferences, its favorite water temperatures, and much, much more.

The program is called GLATOS, and that is not a Greek god you forgot about from mythology class. GLATOS is in that pea soup of acronyms that are part and parcel of the intensive study of the lakes, and it stands for Great Lakes Acoustic Telemetry Observation System.

There is a network of receivers spread throughout the Great Lakes, and each time one of the several hundred walleyes carrying a transmitter is within range, the receiver picks up a ping that is distinct to that particular fish.

The receivers form a picket line across the western end of the lake, in a single strand from Point Pelee to the north end of Pelee Island, and in multiple strands from the south end of Pelee Island to Kelleys Island, and from Kelleys to the mainland. There are also receivers in the Central Basin, and at Rondeau Bay on the Ontario shoreline, and in the Maumee River.

The fixed receivers are anchored to the lake bottom, where they store information on when a ping from a certain fish was received, and what conditions were present at the time. The study is in its very early stages, but when those receivers are retrieved and brought back to the Ohio Division of Wildlife Sandusky Fisheries Research Station where he works, Vandergoot is bouncing off the walls to get at the data.

Earlier studies that involved just external tags could only tell biologists that a fish had traveled from point A to point B, but the mysteries and the mother lode of information involve what takes place throughout the walleyes’ movement.

The GLATOS study should give biologists a much better grasp of migration rates and routes, which particular stocks of fish contribute the most to the Lake Erie harvest, and provide a better understanding of the spawning patterns and preferences of the lake’s walleyes.

“We’re taking the needle out of the haystack,” Vandergoot said.

The first snippets of data have been eye-opening. About five percent of the walleyes that took on transmitters in the Maumee River or out on Lake Erie ended up migrating up the Detroit River, with some moving all the way across Lake St. Clair, up the St. Clair River, and into Lake Huron.

One walleye showed up near Conneaut, some 140 miles from where it had been tagged, while another walleye that was given a transmitter during the spawning run in the Maumee River in 2011 was later detected near Port Colborne in Ontario, in the extreme eastern end of Lake Erie.

“It’s a little surprising,” Vandergoot said. “There’s a lot more mid-lake movement than we thought, and certain fish are moving significant distances. This program is giving us insight into the behavior of these fish that we never would have had otherwise.”

The fish that carry the transmitters, which have a battery life of five years, are also marked with a bright orange fin tag that alerts an angler that catches the fish to a $100 reward for returning the transmitter.

“Anytime we do something like this, it’s a bit of a gamble,” Vandergoot said about the walleye tracking program.

“There are some reservations when we put new technology in place, but the fact that this is actually working, and we get the receivers back and download the data — it’s holy cow, this is working.”

Vandergoot stressed that the tip of the iceberg is all that has been seen to this point, but as more receivers are collected and their data used to broaden our understanding of this precious resource, we will know more about Lake Erie walleyes that we ever have before.

“Just tagging fish is cool and it makes for some great pictures, but getting the data back … for scientists, that’s incredibly exciting. That’s what gets us up in the morning,” he said.

Contact Blade outdoors editor Matt Markey at: mmarkey@theblade.com or 419-724-6068.

Fertilizer limits needed to curb algae problems in Lake Erie

A United States-Canadian agency called on Wednesday for swift and sweeping limits on the use of fertilizer around Lake Erie to reduce the amount of phosphorus entering the water and creating a vast blanket of algae each summer, threatening fisheries, tourism and even drinking water.

In a report on the algae problem, the agency, the International Joint Commission, said that fertilizer swept by rains from farms and lawns was a major source of phosphorus in the lake. It recommended that crop insurance be tied to farmers’ adoption of practices that limit fertilizer runoff, and that Ontario, Ohio and Pennsylvania ban most sales of phosphorus-based lawn fertilizers.

The commission, which studies and regulates water uses in streams and lakes along the border of the United States and Canada, urged Michigan and Ohio to invoke the Clean Water Act to limit phosphorus pollution from farmland as opposed to from factories and other places where pollution can be pinpointed and measured.

The proposals are likely to encounter strong opposition from the agricultural industry and fertilizer manufacturers. Both groups have already asked a federal appeals court to prohibit the Environmental Protection Agency from regulating farm-related pollution from phosphorus and other chemicals along the Chesapeake Bay.

Phosphorus — and especially phosphorus in fertilizer, which is designed to be easily absorbed by plants — is the source of the algal blooms, some of which are so toxic that they have killed dogs and sickened swimmers. Beyond clotting the lake’s surface, decomposing algae consumes the oxygen in the lake’s deep center each summer, creating a dead zone where deepwater fish that are essential to the lake’s food chain cannot exist.

National and state governments rid the lake of algae in the 1980s, ordering big cuts in phosphorus pollution from factories and sewage plants. But the blooms returned in the late 1990s as farmers started applying fertilizer on frozen fields in the winter, and spreading or spraying it instead of injecting it into the ground.

In 2011, heavy spring rains washed so much phosphorus into the lake that the succeeding summer, algal bloom, at 1,920 square miles, was three times bigger than any previous one.

That and other large blooms have crippled tourism in a region where sport fishing and lake recreation are major industries, and they have forced towns and cities to filter and even shut off drinking water. The multibillion-dollar commercial fishing industry could be hit hard. The lake’s growing dead zone has prompted deepwater fish to move upward in search of oxygen, only to run into warmer waters that they find hard to tolerate. Deepwater fish such as perch — a favorite food of one big commercial fish, the walleye — could suffer if the dead zone continues to expand.

“The long-term potential impact on fisheries is something we’re really worried about,” said Donald Scavia, a scientist at the University of Michigan’s Graham Environmental Sustainability Institute.

Although the sources of phosphorus range from leaky septic tanks to storm sewers to ordinary rainfall, the biggest contributor is farming, the report indicates — and the biggest farm source is the fields along the Maumee River watershed in Ohio and Indiana.

Both the United States and Canada have set targets for reducing Erie’s phosphorus load by 2018, but the commission’s report states that those targets are too low. To return the lake to the mostly algae-free state it enjoyed in the mid-1990s, it states, the Maumee’s phosphorus runoff must be cut by 39 percent.

Both governments and private organizations conduct programs that encourage farmers to voluntarily limit fertilizer runoff, but regulatory limits are mostly nonexistent. The commission’s report urges a mix of voluntary and legal programs to achieve large reductions by 2022, with a focus on dissolved reactive phosphorus, the sort used in fertilizers.

The report also states that farmers in lakeside states and provinces should prohibit spreading fertilizer on snowy or frozen ground, where it is most likely to be carried away by melting or rains, and should limit applications in the fall.

For homeowners, the report recommends that Ontario, Ohio and Pennsylvania ban the sale of phosphorus-based lawn fertilizers except during the first growing season of new lawns, or when soil tests show that the phosphorus content is too low. It also says that Michigan and Ontario should require inspections of septic tanks to ensure they do not leak.

Lake Erie Charter Captain’s Conference, March 1st

Captain John nice walleye 

Ohio Sea Grant’s Annual Charter Captains Conference

Huron Ohio — For the 33rd year, Ohio Sea Grant’s Charter Captains Conference will help prepare Lake Erie fishing charter boat captains for the upcoming season by providing updates about Lake Erie’s 2014 fishing outlook, environmental conditions, licensing, regulations, and business management.

The conference will be held on March 1, at the Cedar Point Conference Center on the Bowling Green State University Firelands Campus, and is co-sponsored by the Lake Erie Charter Boat Association and the Ohio Department of Natural Resources, Division of Wildlife.

Jessica Barber, fish biologist with the U.S. Fish and Wildlife Service, will update captains on the service’s efforts to control invasive sea lampreys in Lake Erie. Jonathan Coholich of Navionics will present the company’s newest navigation and sonar equipment, and OSU Extension Tax Field Specialist Larry Gearhardt will offer tax tips to charter business owners.

Other speakers will include representatives from the Lake Erie Charter Boat Association, ODNR Division of Wildlife’s Sandusky Fisheries Research Unit and Lake Erie Law Enforcement Unit, U.S. Customs and Border Protection, the Ottawa Soil and Water Conservation District and the U.S. Coast Guard.