If you spent any time on the water last year, you may have seen Michigan Department of Natural Resources fisheries management units at work conducting fisheries surveys across the state. Crews completed 171 surveys of Michigan’s inland lakes and 110 surveys of Michigan’s streams in 2023.
These surveys are valuable, helping track inland fisheries populations, evaluate stocking efforts to increase angler opportunities and address concerns from anglers.
Collecting key data on Michigan’s world-class fisheries is critical for successful management of the state’s diverse fisheries resources, but what exactly do crews look for? According to Jim Francis, DNR Fisheries Division Lake Erie basin coordinator, surveys fall into three categories:
- Evaluating management actions.
- Understanding status and trends.
- Finding answers to new questions or concerns.
“The management units stepped up this year and were able to safely conduct inland fisheries surveys to evaluate if management actions, like fish stocking or habitat improvement projects, had the desired effect,” Francis said. “Surveys help us understand whether or not our management actions resulted in better recreational fishing in certain areas or improved a lake’s overall health.”
Francis explained that, at fixed status and trends sites, the DNR annually estimates fish population abundance — usually trout in coldwater streams and smallmouth bass in warmer waters — on a three-year rotation, while random site surveys are intended to give a species snapshot and show relative abundance. The DNR collects in-stream habitat data at all status and trends sites.
Fisheries managers use the third category, discretionary surveys, to answer questions or address current concerns, perhaps something raised by a local biologist, an angling group or a lake association. Such surveys, typically accounting for 50% of the department’s annual survey effort, might be conducted to assess habitat suitability for a threatened and endangered fish species.
Such surveys are critical to a detailed, accurate understanding of state fisheries and aquatic health, and the DNR’s ability to regularly complete the surveys is dependent on sufficient, sustainable, long-term funding.
DNR Fisheries Division Chief Randy Claramunt said that under the DNR’s current funding level, an inland lake in Michigan is likely to be surveyed only once every 90 years, which isn’t viable. Fisheries managers use the information from surveys to strategize their actions, detect early indicators of invasive species, recognize developing threats to fish and habitat health, and many other important activities.
“Additionally, anglers rely on this information when planning fishing trips, and many DNR partners depend on these surveys to inform strategic efforts such as habitat protections,” Francis said. “Well-managed, high-quality aquatic habitats and waters are things all residents benefit from.”
If you’d like to learn about the DNR’s lake and stream surveys, especially in your part of the state, contact the fisheries management unit in your area. For more on how the department takes care of fisheries, visit the DNR’s fisheries management webpage.
