The state of Connecticut imposed a ban on the capture of blueback herring last year; it’s now migrated farther up the Connecticut River in a coordinated effort to rebuild stocks.

The small migratory fish are cousins of American shad and have little sporting value to anglers. Historically, herring provided a food source to colonists who caught them in seines along with shad and an occasional Atlantic salmon and stored them in pickling crocks. Because they were abundant and had less food value than shad or salmon, herring were also undoubtedly important spring fertilizer, along with potash and compost. Today in the Connecticut Valley and other Northeastern river valleys, herring are used primarily as bait for striped bass and bluefish, although some people do still pickle them for the table.

Mature, 4- and 5-year-old herring that accompany shad and salmon on their spring spawning runs up the Connecticut River average a foot in length and provide an important forage base for stripers and blues. Then, after they spawn in late May or early June, herring progeny grow to fingerling size in the summer before departing for saltwater in late August or early September. While maturing in the Connecticut, immature herring again provide a valuable forage base, this time for indigenous fish, such as pickerel, pike and bass. These fish can migrate long distances along the coast, feeding and growing in the mid-Atlantic region during winter, the Gulf of Maine summers.

It wasn’t long ago that spring herring were numerous in the Connecticut River, with an average of 300,000 to 500,000 passing the dam in Holyoke annually. The best recorded herring run through Holyoke occurred in 1985, when 630,000 were transported over the dam by its fishlift. But in recent years the numbers have been on a steady decline. Less than 2,000 passed Holyoke last year, and experts believe there’s a direct relationship between that drop and a dramatic striped-bass increase.

So, now, the Connecticut River Atlantic Salmon Commission (CRASC) has approved a basin-wide management plan that will protect blueback herring from Long Island Sound to Bellows Falls, Vt.

“This plan will focus efforts of resource management agencies to restore herring from the current annual return of thousands to hundreds of thousands,” said CRASC chairman Edward C. Parker, “The plan is about bringing back a historic fishery that is as important to a balanced ecosystem as it is to the river’s many anglers.”

CRASC is an interstate, multi-agency commission created by Congress in 1983 and reauthorized in 2002. Members include the states of Massachusetts, Vermont, New Hampshire, and Connecticut, and the United States Fish and Wildlife Service and National Marine Fisheries Service. Its mission is to restore runs of migratory fish to the Connecticut River and its tributaries.

The new initiative calls for the protection, management and enhancement of the blueback herring population through fishing regulations, improved fish passage, and trap and transfer of herring to establish self-sustaining populations.

Many upstream fish-passage facilities have been constructed on Connecticut River dams over the past 50 years to make the upper reaches of the river system accessible to anadromous fish, primarily shad and salmon. Similar fishways have also been constructed on tributary dams, and the plan is to build more in coming years to open potentially important nursery streams to anadromous fish. On the Westfield River in Massachusetts and the Ashuelot River in New Hampshire, agencies have been capturing fish below dams and transporting them above the manmade obstacles. This is scheduled to occur on other tributaries under the new initiative.

The program’s stated objective is to restore and maintain a sustained run of 300,000 to 500,000 herring through Holyoke each spring. Additional research is also planned to refine the actual population goal and better understand the cause of the recent herring-population decline.

In the 1990s, the U.S. Fish and Wildlife Service, concerned about low stocks of striped bass along the Eastern Seaboard, led an aggressive, cooperative program aimed at rebuilding stocks. It was a ringing success. By 1995, striped bass were flourishing. Since then, blueback herring populations have been on a steady and alarming decline, leading biologists to their conclusion that the comeback of bass contributed to the demise of herring.

The pertinent question is: Why the problem now? Didn’t stripers and blueback herring historically coexist just fine? “Perhaps they did,” responded U.S. Fish & Wildlife Service Connecticut River Coordinator Janice Rowan. “The question today seems to be one of an ecosystem out of balance.”

And, indeed, officials are aware that other dynamics have contributed to the declining herring populations — factors such as pollution, dams, commercial and recreational fishing and competition from new species that have expanded their range from the south into the Connecticut River. But Connecticut Department of Environmental Protection fisheries biologist Steve Gephard thinks it’s more important to immediately implement a plan to reverse the herring population’s downward trend than to pinpoint the source of the problem.

“Regardless of the contributing factors,” Gephard predicted, “the activities presented in the plan — conservation regulations, fish passage and transplantation — will help build the Connecticut River herring run.”

That sounds like a safe assumption. So should we anticipate a blueback herring comeback?

That remains to be seen.