Skip to main content


A Desktop Approach to Assessing Lake Whitefish Stocking Feasibility

By Uncategorized


Lake whitefish (Coregonus clupeaformis) numbers are declining substantially in the Great Lakes, concerning fishery managers and the commercial and tribal fishers who highly value the species. The public increasingly shares this concern due to media coverage that illuminates fishery stressors and recovery prospects. This edition of Research Notes highlights recent research contributions on lake whitefish supported by the Great Lakes Fishery Trust.

In 2019, a team from the Michigan State University Quantitative Fisheries Center evaluated the feasibility of stocking lake whitefish to rehabilitate or supplement the Great Lakes fisheries. James Bence, Travis Brenden, and Emily Liljestrand, as research team members, sought to determine the stocking numbers that would be required at different lifecycle stages to yield substantial benefits as well as the resources required to produce those numbers. Their desktop analysis focused on Lakes Michigan and Huron, using available information from primary and secondary literature combined with expert perspectives on culturing fish in the Great Lakes region.

The project sought to understand whether stocking fingerling or yearling lake whitefish could yield numbers for the fishery significant enough to offset declines. The research project was comprised of these components:

  • Identify plausible survival rates for lake whitefish life stages through a review of primary and secondary literature
  • Estimate costs associated with culturing lake whitefish to later life stages through expert consultations
  • Calculate anticipated yield per recruit for the study area through existing lake whitefish stock assessment
  • Develop a cost-benefit of multiple lake whitefish stocking scenarios

Lake Whitefish (Coregonus clupeaformis)

Key Findings

The research team found that stocking fall fingerlings or yearlings gives the best chance of survival. However, the research team’s modeled results suggest that the financial resources required to establish a stocking program would exceed the economic value of the anticipated additional yield.

Beyond the Key Findings

Actual survival rates of stocked fish are highly uncertain, and the team could have used plausible alternative values in its calculations, resulting in different outcomes from the stocking scenarios. These caveats aside, by conducting the cost-benefit analysis, the research team was able to provide the anticipated costs of stocking lake whitefish in numbers that recover yield. The work also demonstrated how readily available information can be compiled and synthesized to develop a cost-benefit analysis regarding stocking as a potential fishery management action in the Great Lakes. Moreover, the team’s research suggests work is needed on evaluating early life survival of hatchery-reared lake whitefish in the Great Lakes and on reducing costs of lake whitefish culture.

Research Collaboration

The team’s research and understanding on lake whitefish fisheries, culturing fish in the Great Lakes, and costs associated with methodologies in culturing lake whitefish to different life stages was enhanced through interactions with experts from the Ontario Ministry, Michigan Department of Natural Resources, U.S. Fish and Wildlife Service, Sault Tribe of Chippewa Indians, Little Traverse Bay Bands of Odawa Indians, and the Bay Mills Indian Community. These state, federal, and tribal management agencies provided expertise on whether survival rates identified from the research team’s sources and subsequent evaluations were sound.

I think an important outcome of the work is that it could focus research on early life survival of hatchery-reared lake whitefish or viable approaches to reduce costs of culturing lake whitefish.

James Bence, Ph.D.Primary Investigator

Learn More

For more information about the study design, results, and implications, see the Quantitative Fisheries Center Technical Report from the Michigan State University Department of Fisheries and Wildlife. For questions, contact the primary investigator, James Bence, Ph.D.,


Research Notes includes the results of GLFT-funded projects that contribute to the body of scientific knowledge surrounding the Great Lakes fishery. The researcher findings and grant result summaries do not constitute an endorsement of or position by the GLFT and are provided to enhance awareness of project outcomes and supply relevant information to researchers and fishery managers.

Salmon swimming up stream

New Study Shows Pacific Salmon Transfer Contaminants to Resident Fish

By Uncategorized

Dominic Chaloner, a research associate professor at the University of Notre Dame, led a team of scientists to assess the extent to which Pacific salmon migrating from the Great Lakes into tributaries during their spawning runs increase contaminant levels in local fish populations. The team focused on mercury and persistent organic pollutants (POPs) such as polychlorinated biphenyls (PCBs), given their prevalence in the Great Lakes Basin.

Read More

New Vessel Fills Great Lakes Research Niche

By Uncategorized

The 69-year-old research vessel (R/V) Chinook was fast approaching retirement. After years of generating valuable research data on the Great Lakes fishery for the Michigan Department of Natural Resources (MDNR), it was nearing the end of its useful life. Enter the R/V Tanner, a state-of-the-art 57-foot aluminum-hulled vessel with all the modern equipment its crew could hope for. This new member of the fleet, named after former MDNR Fisheries Division chief and director Dr. Howard A. Tanner, was funded in part by a grant from the Great Lakes Fishery Trust (GLFT). Although the Chinook will be missed, the Tanner is a welcome replacement that will enhance data collection and management decisions for years to come.

Read More

New Method Available for Estimating Relative Recruitment Levels

By Uncategorized

Thanks to a recent GLFT project, fisheries managers now have two computer models, developed by a team of researchers who wondered if they could find a better way to determine relative recruitments of spawning populations in a mixed environment. The researchers maintained that if they could identify that certain vulnerable populations contributing individuals to a mixture had declining recruitment levels, then fisheries managers could better employ appropriate conservation measures.

Read More

Characterizing Sources of Thiaminase in Great Lakes Food Webs

By Uncategorized

In order to understand Thiamine Deficiency Complex (TDC)—which contributes to premature death in lake trout—researchers looked into whether certain fish genes produce thiaminase (a protein that breaks down vitamin B) de novo, or at a cellular level. This project will help scientists to recommend the next actions in order to reduce or manage TDC in Great Lakes fish.

Read More

The Role of Tributaries and River Plumes as Nursery Areas for Yellow Perch and Round Gobies in Lake Michigan

By Uncategorized

In the warmer waters of spring, yellow perch lay their eggs in long, gelatinous strands, usually among the thick vegetation found in the shallow waters of rivers and along the shores of lakes. A single female can lay more than 20,000 eggs; however, the vast majority of fish that come from these eggs will die very early, primarily due to predation and starvation.
To cultivate self-sustaining stocks of fish, fisheries managers need to understand how best to help young fish survive. For example, among all the different habitats in and around Lake Michigan, are there particular ones where larval and juvenile yellow perch—as well as other species, like round gobies and alewives—can find the food and water conditions they need to thrive? And how do these fish use different habitats as they grow?

The Angle

A team of researchers hypothesized that river plumes—which have unique thermal, light, nutrient, and biological properties—would provide an excellent place for larval yellow perch, round gobies, and alewives to grow. They also wondered how the three species used river mouths, river plumes, and the nearshore waters of southeastern Lake Michigan. Did the young fish function the same regardless of their environment, or were there important differences among habitats?

The Nitty-Gritty

To test their hypotheses, researchers (1) collected water samples from river plumes and adjacent nonplume areas in southeastern Lake Michigan to compare their physical, chemical, and biotic conditions; (2) estimated the movement of larval fish from tributaries into Lake Michigan; (3) compared the densities, diets, and growth rates of the three species in different areas; and (4) evaluated the extent to which later-stage fish used tributaries and river plumes as early life habitats.

The interdisciplinary research team—which included, among others, a fish ecologist, a physical scientist, and a water isotope specialist—used a number of different tools and methods (including otolith isotopic analysis) to better understand fish movement, as well as habitat contributions and linkages.

The Results Are In…

The researchers found that, while river plumes in southeastern Lake Michigan present a somewhat different environment than open lake waters (they are a little bit warmer and more turbid), they are very small and not the hotspots of production that researchers anticipated. Data do suggest, however, that river mouths have greater potential for production, particularly for alewives.

Perhaps the most important finding, though, is that there was a clear distinction between river mouth and nearshore populations of yellow perch and round gobies, but not alewives. An analysis of diets, fatty acids, and stable isotopes, as well as isotopic analyses of otoliths, show that alewives move back and forth between the habitats (the river and the open lake water) with some regularity, while yellow perch and round gobies stay mostly in the same habitat for life.

What Does It All Mean?

Although river plumes were not as productive as researchers originally surmised, river mouths show some promise as production hotspots and, therefore, warrant further study. They may be particularly good environments for larval alewives. Given recent concerns about the considerable year-to-year variations in the alewife population, and their important role as prey for other valuable fish, river mouths may hold some management answers.

More important, however, is that fish managers now have a clearer understanding of the yellow perch,  round goby, and alewife populations. This information could be of great value when making decisions about regulations for managing these species and helping more larval and juvenile fish survive.

 Use the Link Below to Read the Complete Article

Full Article

Study Prompts New Thinking About Yellow Perch, Round Gobies, and Alewives

“The fascinating thing about research,” says Jon Beard, grant manager for the Great Lakes Fishery Trust (GLFT), “is that it’s not just about proving or disproving a hypothesis. Sometimes the most interesting results come from other knowledge gained along the way.”

This was true of a recent GLFT-funded project, which aimed to determine how tributaries and river plumes serve as nursery areas for certain fish species.

“One of the most interesting findings in this project from a fisheries management perspective is not that river plumes weren’t hotspots of production, but that researchers found that yellow perch and round gobies in nearshore Lake Michigan and river mouths rely on distinct trophic pathways and do not appear to move frequently between the two habitats,” Beard says. “This information has real potential for use by management agencies.”

In fact, the GLFT has already funded another study to expand understanding of the topic.

Alewife (Alosa pseudoharengus).

Originally, the research team focused its attention on evaluating the production potential of river plumes. In the process of characterizing and evaluating them, researchers asked two other important questions: How do juvenile yellow perch, round gobies, and alewives use different habitats (including river mouths and the open lake)? And how do those habitats support fish growth?

To answer these questions, the research team looked at the diets of the fish and at different bio-chemical indicators. These indicators included fatty acids and stable isotopes, which scientists use to assess the type of production pathways that support fish growth.


Yellow perch (Perca flavescens).

Tomas Höök, associate professor in the Department of Forestry and Natural Resources at Purdue University and one of the grant’s principal investigators says, “We found distinct signatures in the stable isotope ratios and fatty acids of yellow perch and round gobies in the open lake versus those in the river mouth.” That means that, for the most part, those fish do not go back and forth between the lake and the river; instead, they stay primarily in the habitat where they were caught.

“We saw the isotopic values we would expect to see of fish that have spent their lives almost entirely in the lake or almost entirely in the river mouth,” says Höök. The same was not true, however, of alewives. Because they are more migratory by nature (alewives live in the lake and run into the river to spawn), their fatty acid and isotopic signatures were similar, regardless of the habitat in which they were found.

These findings were reinforced when researchers examined the otoliths in the three species. As Höök explains, “Otoliths are a more or less biologically inert structures in the heads of fish that grow like crystals. They start as very small crystals and, as the fish grow, material is deposited onto the otoliths. Once material is deposited, it’s not sequestered back into the body, so it can give us an idea of the different environments a fish has experienced over time.”

With each of the three species, the research team analyzed the isotopic makeup of the edge and the middle part of the otolith to determine where it had lived. Not surprisingly, in most cases, when it came to yellow perch and round gobies, the core otolith signature was similar to the environment in which the fish were caught, whereas the otolith signatures of alewives were not.

“These findings suggest that yellow perch and round gobies may have a more complex spawning stock structure than alewives in Lake Michigan, which has important management implications,” says Carl Ruetz, professor with the Annis Water Resources Institute at Grand Valley State University. “For example, if yellow perch are composed of numerous subpopulations along the periphery of the lake, managers will need to recognize and account for that diversity when formulating regulations related to yellow perch management.”

More research is needed to determine whether this is the case.

Another finding managers may find useful is that while river plumes were not hotspots of production, as researchers first hypothesized, river mouths appear to hold more promise. “The conditions in the river mouth seem to be good for some fish,” explains Höök. “It’s warmer, it’s turbid, and we found that larval alewives, in particular, are growing better there than in the open lake.”

Given recent concerns about the high variability in alewife populations from year to year, as well as their role as important prey for other valuable fish, river mouths may hold some management answers.

As for the original hypothesis, Höök and the other members of the research team thought that river plumes might be a productive environment for yellow perch, round gobies, and alewives, because they (1) concentrate diverse abiotic (e.g., sediment) and biotic constituents (e.g., bacteria, phytoplankton, zooplankton, and larval fish), (2) stimulate primary and secondary production, and (3) provide thermally suitable conditions. In fact, earlier research on yellow perch in western Lake Erie found that larval survival was, indeed, higher in the Maumee River plume than in surrounding nonplume waters, due to high levels of turbidity (or murkiness). That research suggested that the turbidity of the water probably reduced the ability of predators to find young fish, which increased their survival rate. Höök and his fellow researchers thought they might see similar results in the river plumes of southeastern Lake Michigan.

Mean Densities of Larval Alewife and Yellow Perch

This is a caption.

Mean densities of larval alewife and yellow perch during May through August 2011 and 2012. Alewife densities were generally higher at river sites, while yellow perch tended to be more dense at lake sites.

After collecting samples from five tributaries over the course of two years, the research team did find that river plumes present a somewhat different set of environmental conditions than the open lake. According to Höök, the plumes “are a little bit warmer and the water is a little bit murkier, which may facilitate foraging and protect young fish from predators. You also see a higher concentration of nutrients in plume versus nonplume areas.”

Unfortunately, the plumes in southeastern Lake Michigan are very small, even in the St. Joseph River, which is the third largest river system in the state and the largest river included in the study. The size of the plumes—or more specifically the length of time that critical materials stay in them—matter.

“We found that resident time of water spent in a plume, at the longest, is about day,” explains Höök. “On most occasions, it’s much shorter. So, even though the environment is somewhat distinct, it’s really quite limited.”

In the end, says Höök, “this really is a habitat issue. You have to understand habitat utilization in order to make predictions about the fish population and to figure out how to manage them.”

Because of this GLFT grant, managers now have a better understanding of the yellow perch, round goby, and alewife populations themselves, as well as how they move, how they use different environments, what resources support their growth, and the relative contribution of different habitats to survival. This is important information for managers to have as they work to help more larval and juvenile fish survive.

GLFT Aquatic Connectivity Workshop Proceedings Document Available

By Uncategorized

In 2014, the Great Lakes Fishery Trust convened an aquatic connectivity workshop to identify the types of decision-support tools that resource managers and regulators need and would use to guide decisions on where to improve fish passage or remove dams in the Great Lakes basin.

The workshop convened over 50 participants representing 23 entities from federal, state, tribal, and local agencies; binational organizations; universities; and nonprofits. Participants reviewed existing decision-support tools and discussed their information needs and processes used when developing, evaluating, and implementing aquatic connectivity projects.

The discussion helped identify research needs and information gaps and ways to enhance existing tools to support more effective and efficient decision making.

The proceedings document is available for download below:

Document Download

Exploring Life History Characteristics of Naturalized Versus Stocked Chinook

By Uncategorized

Since the 1960s, the state has been stocking Lake Michigan with Chinook salmon to help maintain the lake’s ecosystem and provide diverse fishing opportunities to anglers. As a result, more than half of the Chinook in Lake Michigan today are naturalized. But how has the salmon population changed over time? And are there significant differences between naturally produced and hatchery-stocked populations—differences that could upset the delicate balance of the state’s fisheries?

Since Michigan depends on the economic benefits of recreational fishing—and since the health of the lakes depends on making sound management decisions—the Great Lakes Fishery Trust (GLFT) funded a research project to (1) better understand the state’s more naturalized Chinook salmon population, (2) assess potential differences between naturalized and hatchery-stocked fish, and (3) use the results to inform decisions about cultivating self-sustaining stocks of desirable introduced species.

The Angle

To better understand how the Chinook salmon population has changed over time, a team of researchers from five organizations first looked at historical trend data. Then, the team conducted field studies to gather more information on the life-history characteristics of naturalized versus hatchery-stocked populations. Among other things, researchers hypothesized that age and size at maturity would diverge over time (because many life history traits are heritable), and naturalized fish would spawn at later ages and times of the year.

The Nitty-Gritty

Researchers began their work by examining 23 years of data. Then, they conducted field studies for two years to collect biological data on three different spawning populations in northwestern Lake Michigan: (1) a hatchery-stocked population, (2) a naturalized population, and (3) a mixed population whose origins could not be discerned. For each population, researchers evaluated age at maturity, weight and length at maturity, fecundity, egg size, and the months in which fish spawned. They also analyzed the total thiamine concentrations in Chinook egg subsamples to determine whether egg and larval survivability differed among the populations.

The Results Are In…

Much to their surprise, researchers found only minor differences in the life-history traits of the Chinook salmon population. Even as the population became more naturalized, data show that maturity at age did not change; length at maturity remained consistent; and the average weight at maturity declined, but only slightly. There also was a decrease over time in the ratio of males to females, but the decline was not as significant as expected.

When using more current field data to compare the three Chinook populations, researchers found no support for concerns about differing ages and sizes at maturity, fecundity, or the times at which the fish spawned. They did, however, find that mixed populations had the largest and heaviest eggs, whereas naturalized populations had the smallest.

One of the most interesting and unexpected findings was that egg thiamine concentrations, on average, were above the ED50 threshold (concentrations below the threshold are associated with 50 percent larval mortality). In fact, concentrations were higher than those previously reported, and there was no indication of high occurrences of thiamine deficiency. This finding is noteworthy because Chinook salmon now consume alewives, the primary driver of thiamine deficiency in Great Lakes salmonids.

What Does It all Mean?

While divergences between hatchery and naturalized Chinook salmon populations have become a serious concern in other areas of the country, this project data suggest there is no need to be overly worried about differences in the Great Lakes region, at least at this time. The life-history characteristics of the overall Chinook salmon population have remained fairly stable, and the characteristics of naturalized populations are similar to those of hatchery-produced populations. Therefore, the results suggest that an increasingly naturalized Chinook salmon population has neither adversely affected the salmon fishery nor will it do so in the future.

 Use the Link Below to Read the Complete Article

Full Article

Research Shows Few Differences Between Naturalized and Stocked Salmon

Mark Rogers, a research fishery biologist with the U.S. Geological Survey and one of the primary investigators on a recent project funded by the Great Lakes Fishery Trust (GLFT), posed this fundamental question: As the population structure of Chinook salmon in Lake Michigan changes, should we expect the fishery to change, too? Project results suggest the answer might be no, or least not as much as we might expect. Given current concerns about the vulnerability and sustainability of the Chinook salmon population, this could be an important finding.

For their GLFT-funded project, Rogers and a team of researchers attempted to answer his question by looking at life-history characteristics in two ways. First, they examined 23 years of historical data to determine whether average life-history parameters changed as the Chinook salmon population became increasingly naturalized. (Naturalized fish now comprise more than 50 percent of the total Chinook salmon population in Lake Michigan.)

Second, the team conducted two years of field studies to gather data that might support or call into question what the trend data suggested. For the field study, researchers looked at spawning populations in northwestern Lake Michigan that were naturalized, hatchery-stocked, and mixed (e.g., their origins could not be discerned).


In a third part of the project, researchers analyzed the total concentrations of thiamine, a vitamin B structure, in Chinook eggs, which has implications for egg and larval survivability. Specifically, they wanted to understand whether naturalized salmon were less inclined toward thiamine deficiencies, which, at certain levels, can lead to early mortality syndrome.

Many of the team’s findings were entirely unexpected, Rogers says. For example, researchers were fairly confident that naturalized fish would reach maturity later, which would cause them to spawn at later ages and at later times of the year (perhaps in October and November instead of August or September). Neither the trend data nor the field study data supported this hypothesis. Age at maturity did not change, length at maturity remained the same, and the time of year at which fish spawned showed no significant differences.

Randy Claramunt of the Charlevoix Fisheries Research Station, who served as a collaborator on the project, was surprised with this finding.

“Anglers often ask us if we have to manage wild salmon separately from stocked fish because wild fish are thought to spawn at older ages and later in the year,” he says. “The findings from this study show that wild and stocked salmon likely are not distinct subpopulations. Therefore, our current models on salmon abundance adequately reflect the mixed population.”

The only noticeable change in the salmon population over time was a slight decline in average weight. The decline, researchers learned, was not related to something inherent to the population, or even to stocking density (e.g., too many fish going after too few prey). Instead, they found that weight variations had a stronger relationship with prey fish abundance.

“In years where more prey was available, the fish were heavier,” Rogers says.


Chinook salmon (Oncorhynchus tshawytscha).

Another unexpected finding was that the ratio of males to females did not decline as precipitously as anticipated. The assumption that the population would reach a male/female balance over time is based on the fact that hatchery-stocked fish grow very fast during the first year of life. As a result, male fish reach maturity at age one or two instead of the expected age of three or four. These early maturing males are called “jacks.” Researchers surmised that as naturalized fish contributed more to the salmon population, there would be fewer jacks, thereby equalizing the number of males and females in the spawning population. The trend data from the GLFT project suggests that, while there has been some shift over 23 years, it is not as strong as expected. The Chinook salmon population in Lake Michigan is still male biased.

Yet another surprising finding relates to fecundity. As Rogers explains, “There is an evolutionary paradigm that the number and size of eggs a fish produces should be optimized for the habitat in which they are laid to maximize their survival. So, if you’re in a stable habitat—like a hatchery—the fish will invest its energy in making small eggs and a lot of them. But, if the fish is in a less stable habitat—maybe one with high and low water levels or other stressful conditions—it will invest its energy in laying fewer eggs that are larger.”

Ironically, researchers found that naturalized Chinook salmon, who live in less stable environments than hatchery-stocked fish, laid the smallest eggs. The mixed population had the largest, heaviest eggs, and the eggs of the hatchery-stocked population were in the middle. Among the three populations, however, there were no differences when comparing the total number of eggs laid to a female’s weight.

“If the naturalized fish had much larger eggs than the hatchery-stocked fish, that would imply the naturalized females were putting more energy into their eggs,” Rogers says. “If that energy comes from prey resources, the current prey biomass levels we’re experiencing in the lake, which are lower than in previous decades, could hurt the naturalized Chinook population. Since that’s not the case, we probably don’t have to worry.”

The final, and perhaps most unexpected, finding was that, on average, Chinook salmon egg thiamine concentrations were above the ED50 threshold (egg thiamine concentrations below ED50 are associated with 50 percent larval mortality).

“Thiamine is a vitamin B structure. Thiaminase is a vitamin B blocker that some prey fish have, like alewives. When the salmon consume the alewives with thiaminase, it inhibits thiamine production, which is important to egg and larval survival. So, having higher than expected levels of thiamine in salmon is good.”

While the findings of this study shed valuable light on the Chinook salmon population, Rogers cautions that they do not tell the whole story. The study only looked at fish in northwestern Lake Michigan; therefore, the results do not necessarily represent lakewide patterns. Furthermore, the study focused primarily on the increasing contribution of wild fish to the population. But as Rogers points out: “A lot has been going on in Lake Michigan since the conclusion of our study … that could affect the dynamic of the salmon fishery. So, while our results don’t suggest that the fishery is going to change, there are other things that could change it.”

Field Study Area and Survey Location Maps

Map of field study areas and creel survey locations for Lake Michigan salmon life history conducted during the fall of 2012 and 2013 (left). Map of rivers and creeks where Chinook Salmon samples were collected for historical analyses (right).

Mark Coscarelli, trust manager for the GLFT, agrees with Rogers.

“While the data suggest that there are far fewer differences among naturalized and stocked fish than we imagined, the project underscores that life history characteristics are only one piece of a complex puzzle that drives salmon production in Lake Michigan,” he says. “As we witnessed with Lake Huron, the changing food web brought about by invasive species likely has far greater implications for the fishery.”

Making Trend Data for Fish Populations in Michigan Streams Available Online

By Uncategorized

Visit the DNR Stream Fish Population Trend Viewer Website

Grant at a Glance

With a few clicks, users can access trend data for selected Michigan fish populations. Thanks to the Michigan Department of Natural Resources (MDNR) Fisheries Division, the Stream Fish Population Trend Viewer makes gathering this type of information easier and more accessible. With the viewer, users can simply get online to access information about fish population trends in specific rivers and streams that serve as fixed data-collecting sites for the MDNR. The viewer holds information on more than 40 inland waterways, including Bear Creek, the Huron River, the Manistee River, and the Pere Marquette River. Fish species the viewer tracks are brown trout, smallmouth bass, coho salmon, rainbow trout, and brook trout.

The Angle

The Stream Fish Population Trend Viewer was developed to serve as a simple, centralized location for users to get up-to-date information on regional and local fish trends. The map-based displays were designed to be interactive, allowing users to pick the fish species they want to view, instead of going through biologists at the MDNR Fisheries Division.


The Nitty-Gritty

The project team took data previously collected from the MDNR Fisheries Division, compiled it, and put it online—which is not as simple as it may sound. The process happened over the course of two years. Troy Zorn of MDNR Fisheries Division served as the project manager for the research, and his team worked with a number of resources to make the trend viewer come to life.

Most of the data came from the Status and Trends Program (STP), a statewide inventory effort used to monitor and document long-term fish population and habitat trends. Zorn and his team collected STP data that goes back more than 40 years and incorporated it into the trend viewer. The team then worked with software developers from Michigan State University’s Remote Sensing and Geographic Information Systems center to create the trend viewer. Development efforts were coordinated with Michigan Department of Technology, Management & Budget staff, which put the trend viewer on State of Michigan servers.

The Results Are In…

The Stream Fish Population Trend Viewer is a tool that enables users to be more knowledgeable about trends in the Michigan stream fish populations. It’s a do-it-yourself alternative to getting this type of information from biologists. Now that information is put into the public’s hands, biologists can use the time saved to focus on other areas of their jobs.

What Does It All Mean?

Now that the Stream Fish Population Trend Viewer is in place, the MDNR Fisheries Division will use the results from its STP to annually update the trend viewer. The viewer standardizes data so people are able to run their own analysis and also increases users’ knowledge of the STP fixed-site survey program. One of the MDNR Fishery Division’s goals is to make this kind of technology a standard practice to serve anglers, nonprofits, agencies, and tribes.

Q&A with Catherine Riseng

By Uncategorized

Q&A with Catherine Riseng

Dr. Catherine Riseng, Assistant Research Scientist at the University of Michigan  

CRDr. Riseng worked with a team to develop the Great Lakes Aquatic Habitat Framework (GLAHF), a database used to classify habitats for different species within the Great Lakes basin. The GLAHF was developed over the course of four years. It is currently in its last year, with plans to maintain the database going forward.

The GLAHF was designed as a way to classify habitats throughout the Great Lakes basin and includes spatial data such as biological populations, agricultural census, water temperature, ice cover and more. How will it be used and who will be its primary users?  

Researchers will be able to use the spatial data as input for their projects. They can also look at how their data matches up with what’s already in the GLAHF. Management agencies could look at habitat statuses, or where sampling locations are. If agencies are monitoring the Great Lakes at different locations, the GLAHF database would be a good place to see where other agencies are monitoring, where there are gaps, and where they can plan new monitoring efforts accordingly.

Why is it important to have this kind of classification and framework for the Great Lakes?  

There’s nothing out there that can be used to link all of the different geographic information systems (GIS) projects, research, and monitoring together in one place. The GLAHF allows people to see all the data that’s out there and use it to better guide restoration or management planning and monitoring. The GLAHF is a special framework that can link data from different projects. There really has been no basinwide classification for the Great Lakes that’s been done so far. It has been done for individual lakes, but not for the whole basin.

The GLAHF is binational, which is another thing that makes it unique. It covers both the U.S. and Canadian side of the basin.

Considering bicoastal coordination can sometimes be difficult to manage, how did the GLAHF team engage Canadian resource managers? 

That’s been an effort of ours all along. We’ve been incorporating representatives from Canadian agencies and universities as part of our advisory team, and integrating binational perspectives through meetings and workshops. We’ve also been engaged with binational teams leading two of the Great Lakes Water Quality Agreement 2012 Annexes, which make sure the United States carries out its commitment under the agreement. There are ten annexes within the agreement and each one focuses on specific issues.

We work hard to incorporate input from agencies managing both sides of the border to ensure that GLAHF is relevant binationally. We also recognize the sampling programs, data management, and data sharing policies vary within agencies, but also across the border. We’ve been working through some of those barriers.

What is the plan for ongoing GLAHF maintenance? 

Right now GLAHF is housed within the Institute of Fisheries Research at the Michigan Department of Natural Resources (DNR). The DNR has also supported one part-time person to continue to update and maintain the data. I think we are still looking for additional support from federal agencies to help with adding more data and increasing GLAHF’s functionality in the future.

You recently had a manuscript on the GLAHF published in the Journal of Great Lakes Research. What else are you doing to promote the tool?

We present at academic conferences. At these, we host workshops to familiarize attendees with the framework, the data, and the Web-based tools we have been developing. We also host monthly webinars to keep all of our project advisers up to speed and get feedback on project developments. We are currently completing the GLAHF website, which describes the project and the various components, provides access to the framework and data, and has links to the metadata and decision-support tools being developed under U-M Water Center funding.

GLAHF funding is in its fourth and final year. What are you doing with the time you have left? 

We are developing a website that will have a user interface within the GLAHF database. We’re going to share the results and actively get feedback from the people demonstrating the website in a hands-on fashion. We’ll also be holding a couple of workshops—one in the U.S. and one in Canada—with the same purpose, but it will be a lot more hands-on. We have a couple of other manuscripts coming out; one looks at spatial variation in water temperature and ice duration. It will demonstrate how the GLAHF is used for additional research in order to investigate the effects of climate change.

What else do you have in store for the GLAHF? 

We have two spinoff projects from GLAHF. One is to develop a user interface decision-support tool. The other is a project we started with the Great Lakes Basin Fish Habitat Partnership, where we do an assessment of nearshore habitat using the GLAHF framework.


Courtesy photo of Catherine Riseng