It’s been a hot-button issue with advocates for years: how to best protect and restore dwindling stocks of river herring.

As the New England Fishery Management Council’s (NEFMC) June 20 vote drew nearer, those who have been fighting for more stringent herring protection regulations ramped up their campaigns. For roughly three years, they’ve been collecting data, monitoring stocks and advocating for stricter rules regarding offshore trawlers.

Last month, the NEFMC voted in favor of implementing 100 percent at-sea observer coverage on offshore trawlers, a measure that will go into effect next season.

The observer option beat out a “move along” measure supported by fisheries, where a monitoring system would alert fishers to high concentrations of herring in a specific area. Another option would have closed “hot spots,” or known areas of high herring concentration, to trawlers completely.

River herring are anandromous fish, which means they live in the sea but spawn in fresh water. Though not a commercially marketed fish consumed by humans, herring play a major role in the ecosystem and serve as prey for other fish and mammals.

According to recent counts, the numbers of river herring in Buckeye Brook are up from past years. This year, they tallied 90,625 herring or “buckeyes,” in comparison to 5,010 in 2004. Experts say the numbers are still too low; herring counts at Gilbert Stuart, which at one time boasted 300,000 fish, are still wavering around 100,000.

Paul Earnshaw, president of the Buckeye Brook Coalition and river herring advocate, said the vote to implement at-sea observers is a step in the right direction.

“What we’re going to get is accountability,” said Earnshaw.

According to Herring Alliance data, 2.5 million river herring were caught and killed each year between 2005 and 2008. The millions of herring weren’t caught intentionally; they were caught as bycatch, or the fish and mammals accidentally ensnared in the nets of large offshore trawlers. Typically, the bycatch gets crushed under the weight of the other fish and dumped back into the sea.

Earnshaw believes the onboard observers will take note of how many herring are being caught as bycatch, a crucial step in protecting and restoring their population.

“We’re going to know precisely what they’re catching out there,” said Earnshaw. “It’s going to be quite evident there’s a high bycatch.”

The onboard observer will be a third party not associated with the fishing company, and will be present on every trawler’s voyage.

In addition to monitoring the amount of herring caught, onboard observers will discourage the dumping of dead fish at sea, unless it is an emergency.

The NEFMC also voted to implement a limit on bycatch annually. The cap has yet to be determined, and will be discussed in the coming years. The limit is set to go into effect in 2014.