Four Michigan Native American Tribes reached a tentative deal with the federal and state governments to split up the next 24 years-worth of fishing access in Michigan’s Great Lakes waters.

The proposed deal maintains broad tenets of an old agreement that has been in place since 2000, while giving tribal anglers access to new fishing locations, gear and species in response to dramatic declines in the whitefish populations that sustain their livelihoods.

Parties to the negotiations are the federal and state governments and the Bay Mills Indian Community, the Little Traverse Bay Bands of Odawa Indians, the Grand Traverse Band of Ottawa and Chippewa Indians, the Sault Ste. Marie Tribe of Chippewa Indians and the Little River Band of Ottawa Indians.

But the Sault Tribe has declined to sign on to the proposed agreement.

David Caroffino, tribal coordination unit manager of the Michigan Department of Natural Resources fisheries division, called the proposed agreement a compromise that responds to dramatic changes in the Great Lakes over the two decades since parties last divided up Great Lakes fishing access.

“Everybody needed to figure out what is a new solution given where the lakes are right now?” he said.

Whitefish aren’t the only species in decline. Some salmon populations targeted by recreational anglers are also suffering. The decline in overall fish biomass is a result of dreissenid mussels that have invaded every Great Lake but Superior, hogging nutrients and leaving less food for fish.

“When the 2000 decree was signed, no one could have foreseen that the influx of zebra and quagga mussels was going to severely undercut the amount of whitefish that could survive in lakes Huron and Michigan,” said Kathryn Tierney, tribal attorney for the Bay Mills Indian Community. “And guess what? It’s not obvious how to fix it, either.”

That scarcity increased the potential for conflict as parties to the negotiations sought to replace the 22-year-old consent decree governing nearly 19,000 square miles in lakes Michigan, Huron and Superior.

Parties to the negotiations needed multiple deadline extensions to settle on new terms. And even then, not everyone agreed to sign on.

A spokesperson from the Sault Tribe said tribal officials are not commenting on the case or their reasoning for declining to join the proposal.

Other detractors to the proposal include recreational and charter boat groups who worry expansions to gillnet fishing could threaten the lakes’ fisheries and their interests.

Gillnets are walls of netting placed in the water to ensnare the gills or other body parts of fish that swim into them. In contrast with trap nets in which unintended catch known as “bycatch” to be tossed back alive, gillnets are generally lethal.

When tribes and the state adopted the previous decree in 2000, Michigan spent millions buying out tribal gillnet fishers and supporting a conversion to trap nets. That came amid restrictions on where and under what circumstances fishers could use gillnets.

But with whitefish populations growing sparser, Caroffino said, “those regulations simply don’t work anymore.”

Trap Nets are expensive to operate, and it’s increasingly difficult in today’s Great Lakes to catch enough whitefish to cover those costs. Annual harvests declined from 6.3 million pounds in 2011 to less than 4 million in 2018.

The new decree expands more cost-effective gillnet fishing in key areas. Among them is Grand Traverse Bay, where gillnetters are now restricted to areas beyond the tip of the Old Mission Peninsula. Under the proposed agreement, gillnets would be allowed further into the two arms of the bay during spring and fall.

Allowable catch would still be limited, with adjustments every three years to adapt to changes in fish populations.

The Coalition to Protect Michigan Resources, a group representing recreational and charter fishing interests, opposes the gillnet expansion and plans to file a formal objection to the proposed agreement, said Amy Trotter, executive director of the Michigan United Conservation Clubs, a coalition member.

“We believe the risk to the resource is significant, if the tribes used all of the authorization given in this proposed consent decree,” Trotter said.

The coalition has also filed a request to intervene in the case with the 6th Circuit Court of Appeals. Trotter said she fears expanded use of gillnets will harm fish populations and invite conflict between tribal anglers and state-regulated recreational anglers, reopening old wounds between the two groups.

After repeated disputes over tribal fishing access, a U.S. District Court ruled in 1979 that tribes that signed onto the 1836 Treaty of Washington have legal rights to fish in the Great Lakes. That kicked off negotiations that led to the first consent decree in 1986.

Caroffino said the proposed gillnetting expansion comes with appropriate restrictions to protect fish and minimize conflict. In Grand Traverse Bay, for example, there are limits to how many gillnetters can fish in the bay’s two arms, and they must vacate the area during peak summer recreational fishing season.

But Trotter said she fears aggressive fishing by tribal anglers before Memorial Day would leave few fish for recreational anglers to target once the area closes to gillnetting for the summer.

Beyond the gillnet changes, tribal anglers will have more opportunity to target walleye and perch in some areas, but the new decree also includes new closures to protect spawning walleye and perch.

“There’s give and take on both sides,” Caroffino said, but given the decline in whitefish populations, “we had to figure out, how are tribes going to exercise their treaty rights in a meaningful way?”

The 2000 decree remains in effect while parties await U.S. District Judge Paul Maloney’s reaction to the proposed agreement. A status conference is scheduled for Friday.

But while the tentative agreement represents a major step toward securing another 24 years of cooperation in the Great Lakes, Tierney said, the threat of climate change casts a shadow over the future. Whitefish, which spawn on ice-covered reefs, are particularly vulnerable.

“Even if we could perhaps get a handle on mussels and maybe even control them,” Tierney said, “we will have to deal with other factors that are bigger than the governments who signed onto this document.”