Tracking brookies: NMU student wins foundation grant

By CHRISTIE BLECK

Journal Staff Writer

MARQUETTE — The Rock River might look a little different in the coming weeks.

The Greater Lake Superior Foundation recently awarded the 2017 Coaster Brook Trout Research Grant to Jacob Bowman, a graduate biology student at Northern Michigan University.

Bowman’s project, “A Link Between Metabolic Rate and the Life History Strategies of Brook Trout,” will involve studying the fish in the Rock River in Alger County.

Studying metabolism will be key in his research.

“Every animal’s got metabolism,” Bowman said. “There’s literature that suggests metabolism is tied to different life history strategies. In brook trout, I’m going to relate it to movement.”

Humans, of course, have different metabolisms, but what about fish?

Bowman has at least one question: Is metabolism driving fish to take on certain travel movements or is the action of the fish that are doing these things creating the difference in metabolism?

“We think there’s a clear link,” Bowman said. “What we want to do is look at fish within the Rock River and we’re going to track them, and we expect to see some fish that are going to move long distances and we’re going to see some fish that don’t move long distances.”

There already is evidence, he said, of fish with both movement patterns in the Rock River, which ties into coasters.

“The Rock River is a good choice because it has multiple tributaries, and within those tributaries they all have different habitat types,” Bowman said.

Bowman’s abstract for the project noted brook trout are one of many species that exhibit intraspecific life history variation across their range including Lake Superior, the most notable of which is the coaster brook trout.

Coaster brook trout, though, have been ruled out as a subspecies because of a lack of genetic distinction.

Bowman said his work will apply to coaster brookies, but will focus more on brook trout physiology.

Work will start this summer, with radio frequency identification antennae being put out in various locations in the tributaries. Bowman said passive integrated transponder tags — small tags that can placed in fish abdomens — will be used. Antennae will detect the presence of the tags, which stay in the fish.

Fish will be collected via electroshocking, and two antennae will be placed in a row to determine the direction the fish are moving, Bowman said.

Data goes to a computer bank that indicates the presence of a tag.

The antennae will run most of the year, including winter, and will be operated with solar panels with back-up battery banks. Bowman also will have to keep up with maintenance, including high-flow events.

Bowman’s abstract went into more detail. Oxygen consumption by the fish will be measured for metabolism through intermittent flow respirometry. Causes for movement within a population including thermal and flow variation as well as seasonal movements like reproduction and emigration. The plan is to use these movement patterns in conjunction with metabolism in individual brook trout to determine what metabolic traits correlate with timing of movement, and more importantly, which individuals decide to emigrate from a localized area within the stream.

Bowman will be involved with the project this summer, but NMU biology professor Jill Leonard, who is Bowman’s project adviser and the lead investigator, wants to make it a long-term study and bring in multiple grad students to work on different research aspects.

“The management implications for Jacob’s work as well as the larger project are really to provide basic biological understanding about some of the different characteristics that the public values,” Leonard said in an email. “We know that that the public values brook trout in general, and perhaps coasters in specific. Without understanding what causes brook trout to select their different life history options, it’s hard to know what environmental conditions are necessary to support the species in general and the subgroups in particular.”

If these processes can be better understood, management might be tailored to provide extra support for coasters or for lake resident brook trout as well as the species in general, she said.

Bowman’s project is the first of several projects that will be part of a larger effort from a group working iin the Rock River watershed in collaboration with the U.S. Forest Service.

Leonard said brook trout are an important native species in the region, displaying a wide variety of behaviors that range from living in a stream to dwelling in beaver ponds to spending their lives in Lake Superior to migrating between streams and the big lake.

While this variety can be appreciated — perhaps particularly the presence of migratory forms of the species — the mechanisms that cause it aren’t understood, she said.

“Current data suggests that it is not simple differences between populations, based on genetics, that explain these patterns, so we need to dig deeper to understand what is going on with these fish,” Leonard said. “Jacob will be focusing on the idea that inherent differences in how brook trout manage their energy may be responsible for how much fish move around within our watersheds.”

Bowman has long been an angler of brook trout, which are native Great Lakes fish that are brightly colored in the fall when they breed.

“When I’m fishing for brook trout, I’m in locations that I enjoy being in,” Bowman said.

The habitat, the streams, the fish colors — they all contribute to his appreciation of the brook trout experience.

“When you catch one — that is, decent size — it’s more meaningful than catching a bass or something,” Bowman said.

In one scenario, it’s not that difficult to catch a brook trout.

Tossing a spinner into a stream during the summer can easily result in catching a brookie, he said. It’s harder when an angler goes fly fishing and has to match the insect hatch with the correct artificial flies.

Size also is a challenge.

“Knowing that brook trout do get large, you want to track down bigger fish, that’s where it gets hard, is trying to catch that monster, because there’s just fewer of them, a lot fewer of them,” Bowman said.

His career goals include starting out as a field technician before working for an agency as a biologist. He also just began a job out of Escanaba with the Michigan Department of Natural Resources that involves raising sturgeon.

The GLSF offers $2,000 grants each year to assist graduate students in research on coaster brook trout in Lake Superior or its tributaries. The recipients must be graduate students at a Michigan, Minnesota, Wisconsin or Ontario university or college pursuing a degree in an accredited program of fisheries management, limnology, ecology or biology with a focus in fisheries or a related field.

For more information, visit thegreaterlakesuperiorfoundation.org.

Christie Bleck can be reached at 906-228-2500, ext. 250. Her email address is cbleck@miningjournal.net.