A rift between Canada and the United States was settled on Wednesday after an international agreement was signed, marking the reopening of a fishway.

The fight was over a fish with two different names – one for each side of the border – and a decision made two decades ago to shut the door on those fish returning to the New Brunswick side of the St. Croix River to spawn.

“They spawn in the river and then return to the sea to grow to adulthood and then they return to their native river to spawn as adults,” says U.S. wildlife officer Sandra Larry.

However, it was impossible for the fish to return after the fishway at the Grand Falls Dam closed in the early 1990s.

At the time, Maine officials thought it would protect the small mouth bass fishery, but the decision had a devastating impact on other fish.

The fish are called gaspereau on the Canadian side, and alewives across the border. Historical records indicate that millions of the fish used to swim up the international waterway each year, but a few decades ago, when Maine closed the fishways, the number of fish went from millions to mere hundreds.

Members of the Passamaquoddy First Nation, from both New Brunswick and Maine, are celebrating the return of the important fish to the international waterway.

“No doubt, this is history in the making,” says Chief Clayton Cleaves.

He says the river has provided food for his people for thousands of years.

“Usually people eat them smoked, so they are captured fresh and smoked in the old-fashioned style.”

Geoff Giffin, an angler from the Saint John area, says the experience along the St. Croix River is a familiar one.

“We see it on the Petitcodiac River in New Brunswick. With the gates lifted there, there are fish species that are rebounding,” he says. “There’s all kinds of activity on the river. There are happy angles on the river catching trout.”

Local residents hope the end of the dispute and reopening of the fishway will mean the restoration of the gaspereau fish.

With files from CTV Atlantic's Mike Cameron