Bringing Back the Fish: Michigan Sea Grant Oversees Successful Habitat Reconstruction
|By Stephanie Ariganello, Michigan Sea Grant
The unmanned camera bounced along a rock reef on floor of the St. Clair River. Researchers watched the monitor. Then a long, dark shape came into focus and another and another. The looming figures were lake sturgeon. The team whooped at the discovery: the restoration was working and much sooner than anticipated.
The goals of the project are to:
“It is science in action,” said Jennifer Read, assistant director of Michigan Sea Grant and project lead on the St. Clair River Middle Channel Restoration project. “This is the kind of research project where we’re performing research not just to learn new things, but to apply what we’ve discovered. And with this project, we’ve been rewarded with early success.”
The lake sturgeon were congregating on rock reefs installed as part of the restoration project in the St. Clair River, led by Michigan Sea Grant. The project focuses on restoring fish spawning habitat in order to add young fish to the stocks of several endangered or threatened fish species in Michigan, including lake sturgeon, mooneye, northern madtom catfish and river redhorse suckers. Valuable commercial and sport fish such as walleye, lake whitefish and perch are also expected to use the reefs for spawning.
“Obviously there was a need for more spawning habitat based on the immediate response by the sturgeon,” said Terry Heatlie, habitat restoration specialist with NOAA Fisheries Restoration Center, Great Lakes Regional office. “It’s special because this would not have happened without the restoration project, without restoring spawning habitat in the river.”
click to expand imageReef habitat restoration in the St. Clair River Middle Channel. Credit: Michigan Sea Grant
When given enough time, Heatlie said, some land or water issues heal themselves. With habitat restoration, that is not typically the case. It requires intervention. The construction was completed in June. Nine rock reefs were created, providing an acre of restored fish spawning habitat in the river.
The St. Clair River connects the waters of Lake Huron to Lake St. Clair, where water then flows through the Detroit River and eventually into Lake Erie. The channel is a major shipping route and forms a border between the U.S. and Canada. Because of its location in the heart of the Great Lakes, the restoration has potential to benefit waters upstream and downstream of the construction. The restoration efforts could also provide cultural and economic benefits, bolstering commercial and sport fishing and contributing to a higher quality of life in an area currently listed as an Area of Concern under the U.S.-Canada Great Lakes Water Quality Agreement.
In the early 1900s, the rivers connecting Lakes Huron and Erie were widened and deepened to accommodate larger, modern commercial shipping vessels. Dredging and depositing the materials in different locations in the river damaged fish spawning sites — and subsequently, fish populations.
click to expand imageResearchers inspect egg mats as part of the Middle Channel Restoration project. Credit: Michigan Sea Grant
To compensate for the habitat loss, Michigan Sea Grant and project partners (U.S. Geological Survey, Michigan Department of Natural Resources, U.S. Fish & Wildlife Service, the University of Michigan, NOAA, SmithGroup JJR andMichigan Wildlife Conservancy) constructed two reef projects previously in the Detroit River. The location and design of the Middle Channel reefs were chosen based on studies of fish populations and lessons learned during the previous projects.
“That’s what is really unique about the Middle Channel project,” said Read. “It reflects over ten years of work performed by a multi-agency science team tackling increasingly complex questions over a large geographical area. It represents a successful, system-wide approach to restoration.”
Researchers surveyed the new reefs and collected eggs. It was confirmed. Lake sturgeon successfully deposited and fertilized their eggs on the reefs and the eggs produced viable sturgeon larvae.
Post-construction assessments are planned to ensure the Middle Channel Reefs are being used by a variety of fish species. The goal, aside from reestablishing the habitat, is to help remove the St. Clair River from the bi-national list of Areas of Concern. Two more spawning reefs for native fish are being planned for the St. Clair River in 2013 and 2014, as part of the Great Lakes Restoration Initiative.