When most people think of reefs, they think of the coral reefs found in tropical oceans. This fall, though, a reef of crushed limestone and granite will grow in the fresh waters of the Saginaw Bay.
Beginning this fall, boaters will see workers beginning to restore the Coreyon Reef while documentary filmmakers record the efforts. In the end, the work should reap benefits for anglers and the area economy.
The Coreyon Reef is located 10 miles northeast from the mouth of the Saginaw River. The restoration is expected to span two acres on the floor of the bay. Estimates are that 16,000 tons of material will make up the reef.
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The Coreyon Reef is located approximately 8.5 miles west of Fish Point or about 10 miles north of Quanicassee.The restoration is primarily funded by $1 million from the US Environmental Protection Agency. An additional $25,000 comes from a Saginaw Bay Watershed Initiative Network grant.
The majority of the restoration will consist of crushed limestone, with a coating of glacial granite cobblestone. The cobblestone will be used as the top layer, as it closely replicates native rock reef habitat.
The reefs in the Great Lakes are made of rocks, believed to be deposits left from when the glaciers receded. The reefs act as spawning habitat for a number of fish species, providing a secure environment for eggs to incubate and hatch.
Over time, sediment deposits have destroyed fish habitat, including the Coreyon Reef.
Plans to restore the reef began as part of the walleye recovery plan in the Saginaw River system. Suffering from Michigan’s industrial past, the walleye fish population in the area had fallen far beneath historical spawning habits. The sedimentation in the water destroyed reef spawning habitat for fish in the river system, greatly affecting the number of walleye.
“In the case of Saginaw Bay, most of the inner bay reef habitats have been degraded through sedimentation over the last century or so. That began with the logging era that created a lot of erosion,” said David Fielder, Fisheries Research Biologist for the DNR. “The sediment that would wash into the rivers and streams found its way into the bay and, over time, it would smother this rock reef habitat to where today it’s completely inaccessible or highly degraded and no longer really providing the crevices necessary for fish spawning.”
“It dawned on us, at some point in time during the planning of this, that a million dollars of work is about to be done – all of which is going to get buried in the waters of Saginaw Bay. Without the documentary, it’s going to be a fairly invisible project.”
- Mike Kelly, Director of the Great Lakes Office for the Conservation Fund
The focus is not on increasing the number of fish but expanding the diversity and resiliency to the spawning habitats that exist. The reef is not intended for just walleye, as the restored habitat will benefit the rest of the fish in the area as well.
When DNR fisheries tagged walleye from the Saginaw River, research found that the fish travel north from Saginaw Bay to Lake Huron, with some traveling all the way to Lake Michigan. Other tagged walleye moved south to the Lake St. Clair system. All that adds up to the fish population being too dependent upon a single area for spawning. Restoring the Coreyon Reef will give the fish habitat outside the Saginaw River.
“While we’ve reached our recovery targets number-wise, not all of the processes behind walleye have been fully restored. That’s part of our interest in it. And some that is called like a portfolio effect. You can diversify your sources of reproduction and give them a resiliency,” explained Fielder, “That’s really what we’re trying to do by restoring this particular kind of habitat.”
While many groups are contributing to the project, Bay County played an important role in securing the reef restoration. With topsoil from farmland contributing to sedimentation in the water, Bay County Executive Jim Barcia pushed for legislation to change agricultural practices and keep soil on land. Bay County's efforts were rewarded when samplings found that the sediment load entering the bay had declined. Because of this change in sedimentation levels, grant money to restore the reef was approved.
“Bay County really pushed and forced the issue with both the state and the feds to get this thing done, to get this remedied, so that we could get these reefs restored,” said Laura Ogar, Director of Environmental Affairs & Community Development for Bay County. “We would never be able to fully call ourselves a restored area without these rock reefs being restored.”
The reef restoration is a big project from a habitat perspective but serves as economic development in the area as well. Contributing over $30 million of economic activity annually, the Saginaw Bay plays a significant role in the local economy. Local businesses will further benefit from the growing fish population, as Saginaw Bay was named the 8th greatest lake for bass fishing in the northeast.
Local investments of this magnitude are usually something that residents can walk up to and see when the work is finished. But the significance of the reef restoration is hard for residents to fully realize since it’s underwater. To make the project visible, the reef restoration is being filmed as a documentary.
“It dawned on us, at some point in time during the planning of this, that a million dollars of work is about to be done – all of which is going to get buried in the waters of Saginaw Bay," said Mike Kelly, Director of the Great Lakes Office for the Conservation Fund. “Without the documentary, it’s going to be a fairly invisible project.”
The Conservation Fund has been a part of the reef restoration since the early planning of the project. When the idea of documenting the restoration came up, the group volunteered to lead the effort.
“When this project is complete, we can show people the background of the project and essentially what the project looks like, because we will in fact have underwater pictures of this construction project when it’s done.”
The film will be entered in multiple Great Lakes film festivals and made available online. The group hopes to have the documentary shown on public broadcasting and in local theaters, as well. The documentary is expected to finish shooting in Fall.
Restoration work begins in early August with plans for the project to end later in the month.