Activity: Designing Habitat for Sturgeon

Summary: Students determine the needs of lake sturgeon and, based on those needs, design spawning habitat to help support the recovery effort.

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Procedure

Part 1

As a whole class, read Part 1 downloads, articles and information.

In small groups: answer data sheet questions using lake sturgeon articles as sources of information.
As a whole class: discuss answers from data sheets and what lake sturgeon need to reproduce.

Habitat requirements for spawning lake sturgeon:

  • Rock-on-rock substrate (bottom of waterbody) with interstitial (space between rocks) depth greater than 15 centimeters.
  • Water velocity over the rocks of at least 0.5 meter per second.
  • Water temperature in the range of 9-15 degrees Celsius.
  • Next, explore the location of man-made spawning beds at the southeast corner of Belle Isle in the Detroit River.
  • Notice water speeds are slightly faster at the southeast corner of Belle Isle. This is the site chosen for construction of the man-made spawning beds. (This area has suitable water flow and just needed rocky substrate to become good spawning habitat.)
  • Examine: Huron-Erie corridor Nowcast/Forecast, GLOS

HEC-GLFT-Detroit map
Location of Belle Isle spawning beds.

Part 2

Building lake sturgeon spawning beds in the Huron-Erie corridor.

Lake sturgeon populations have declined in the Huron-Erie corridor. Researchers believe the decline is due to habitat loss and constructing new spawning habitat will help sturgeon populations recover. In June 2004, three spawning beds were constructed by a group of government agencies, led by Michigan Sea Grant.

  • You are a group of experts. Your job is to research and summarize the previous project and propose a new project to create additional spawning beds in the Huron-Erie corridor. You will present your proposal for funding this new project to the Great Lakes Fishery Trust.
  • Select two experts in your group. Research each of the tasks below (project planning, permitting, construction, etc.). When all of the pairs of experts have completed their tasks, work as a group to prepare your presentation for the Fishery Trust.
  • Research lake sturgeon in the Huron-Erie corridor:
    • Using USFWS slides, text and links below research the spawning beds constructed in June 2004.
    • See slides: Sturgeon Slides.pdf
    • Slides 8-11: Biologists captured, tagged and tracked fish to identify preferred habitat
    • Slide 16: Egg mats used to find out which types of substrate sturgeon preferred
    • Slide 17: Types of substrate at spawning sites: Limestone ‘shot rock’ 6-24” in diameter, mixture of coarse gravel and cobble and coal cinders
  • In 2001, plans were made to create spawning habitat for lake sturgeon in the Detroit River, modeled after similar habitat created in Wisconsin. In spring 2002, the U.S. Geological Survey (USGS) and U.S. Fish and Wildlife Service (USFWS) biologists began conducting studies to determine the best location for a man-made, lake sturgeon spawning bed. In order to do that, they:
    • Caught adult sturgeon using gill nets and setlines, tagged sturgeon and tracked their movements to learn about their preferred habitats.
    • Collected fish eggs using egg mats placed on the river bottom.
    • Looked at environmental data — researchers studied water depths, current speeds, river bottom composition, water temperature and water clarity.
    • Researchers used sturgeon and environmental data to determine the best locations to construct the three spawning beds. They found that sturgeon preferred rocky substrate with faster current speeds (greater than 0.5 meters per second).

Project Planning

Next, a Michigan State University videographer shot underwater video and photographs at the proposed construction sites. The engineering company used video and pictures to prepare the construction blueprints. An engineering company (JJR based in Ann Arbor, Michigan) was hired to prepare the construction blueprints.

Permitting

A permit is required before beginning any construction activity that might affect wetlands, alter surface water flows, or contribute to water pollution. The spawning bed construction project required permits from the State of Michigan and U.S. Army Corps of Engineers. Permits were necessary before Michigan Sea Grant could start working with construction companies. The engineering company prepared the construction blueprints and obtained permits through:

  • The Michigan Department of Natural Resources and Environment (now split into the MDNR and the Michigan Department of Environmental Quality) permitting division ensures that projects will not cause environmental harm.
  • The U.S. Army Corps of Engineers ensures that projects are well constructed to provide strong protection of the aquatic environment.

Funding – Where did the money come from?

Grants included:

  • NOAA Great Lakes Coastal Restoration Program – provides funding to conduct restoration projects in the Great Lakes.
  • Great Lakes Fishery Trust (GLFT) – a regional organization to enhance, protect and rehabilitate Great Lakes fishery resources.
  • Donations from local businesses:
    • Businesses will often donate to projects in areas where their business has environmental impacts.
    • DTE Energy is one major company that donates money to local projects.

Expenses

  • 2004 construction costs were $30,000 ($25,000 GLFT and $5,000 NOAA GL-CRG).
  • 2004 management costs were $20,000 ($5,000 GLFT, $10,000 NOAA GL- CRG and $5,000 Michigan Sea Grant).

Contracting with a Construction Company

Michigan Sea Grant solicited bids from five marine contractors. All of the bids they received came in higher than the amount budgeted for the project. It was then that the Michigan Sea Grant representatives met with Faust Marine, Inc. and explained how much money was available for construction. Michigan Sea Grant worked with Faust to reduce the amount of rock that would be used and Faust agreed to do the project within the budget. Faust agreed to construct three spawning beds, one each of large broken limestone, rounded rock and coal cinders.

Construction

Prior to beginning construction, partners (USGS biologists, engineers, permitting agencies, the construction company and Michigan Sea Grant) met to:

  • Write a project construction timeline
  • Finalize the construction materials
  • Review the computer software to be used to monitor construction.

sturgeon reef barge-05Construction occurred June 8 – 18, 2004. During construction, a global positioning system (GPS) unit was used on a crane, along with a survey of the river bottom to monitor placement of materials (7-9 meters deep) in the Detroit River. The engineering company visited the construction site to monitor progress

Monitoring

USGS and USFWS biologists monitored the new spawning beds:

  • August-September 2004 – USGS divers examined construction of the spawning beds and shot underwater video of constructed spawning beds.
  • October 2004 – Biologists measured current speeds at the spawning beds.
  • April 2005 – Biologists looked for adult fish and spawning using minnow traps, gill nets and egg mats and measured environmental parameters (water temperature, clarity and current speed, etc.).

Use of the area prior to construction:

  • Spring 2002 and 2003 – Biologists fished with minnow traps, gill nets and set lines and caught few fish.
  • Spring 2003 – 15 egg mats caught only 135 walleye eggs.

Use of the area after construction:

  • April-May 2005 – Biologists caught dozens of adult fish including walleye, yellow perch, northern hog sucker and shorthead redhorse sucker.
  • April-May 2006 – Thousands of fish eggs from 16 species were found. Seven species of fish spawned at the three new spawning beds, including walleye, yellow perch and lake whitefish.
  • Spring 2006 – Biologists caught and released a 5-foot long, 45-pound male lake sturgeon at the spawning beds.
  • November 2006 – Biologists caught and released four juvenile lake sturgeon 15 miles downstream of the spawning beds. The capture of juvenile lake sturgeon is rare and indicates that lake sturgeon may be spawning at another location in the Detroit River.

Conclusion

sturgeon2-100_2976USGS findings strongly suggest that constructed spawning beds attracted numerous species of adult fish. The restoration and construction of more fish spawning and nursery grounds in the Detroit River and the St. Clair River has become a restoration priority.

Prepare a Proposal

As a group, prepare a proposal to construct a new spawning bed based on what you know from the information above.

  • Select the site for a new spawning bed. Remember: Sturgeon prefer a rocky substrate and areas with faster current speeds. In this case, you will create the rocky substrate.
  • Research current speeds in the Huron-Erie corridor using the Great Lakes Observing System, following the steps below:
  • Go to the GLOS website.
    • Select Huron-Erie Corridor Nowcast/Forecast.
    • Select Terrain map (Base layers – right column).
    • Look for an area in the river with water current speed preferred by sturgeon.
    • Hint – In 2002, researchers mapped confirmed and suspected lake sturgeon spawning locations.
    • Some of these locations had coal cinders substrates, see EPA figure (PDF).

Proposal to Great Lakes Fishery Trust

Develop a proposal with the following parts:

  • A summary of what you know about lake sturgeon and their history in the Huron-Erie corridor. You need to convince the Fishery Trust that restoration of lake sturgeon and their habitats is important.
  • A short description of the previous spawning bed construction project in the Detroit River and evidence that fish are using the spawning bed.
  • Your project proposal should include:
    • A map showing the location of the proposed spawning bed and an explanation of why you selected this location.
    • Project partners: Discuss who will work with you and what makes them qualified to work on the project.
    • Proposed timeline: Estimate how long it will take to plan and construct more lake sturgeon spawning habitat.
    • Proposed budget: Estimate how much your project will cost. Discuss whom else you could ask for funding (organizations are more likely to support projects with several different sources of funding).

Activity Resources

Public outreach related to Sturgeon habitat projects:

NOAA charts: