Alewives in decline
By Johanna Maranto
Editor�s note: This is the first of a three-part exploration of the current plight and past glory of the alewife on the Squamscott and Exeter rivers.
EXETER - A stunning decline in the number of alewife and blueback herring passing through the Exeter fish ladder in the past two years has state Fish and Game Department staff concerned, perplexed and prepared to take action.
In years past, 6,000 to 7,000 herring have made their way from the Squamscott to the Exeter River to spawn, according to John Nelson, head of Marine Fisheries for the department. In 2003, the number plummeted to just 80 fish over the ladder at the Great Dam and rose no higher in 2004.
The time to plan action was at hand. A ban on harvesting alewives and blue backs has been proposed to commence at the end of this month.
The river herring head up the Squamscott from the Atlantic Ocean each spring to spawn, heading over the ladder at the Great Dam, and spawning in the freshwater Exeter River.
In the 1960s, N.H. Fish and Game began the construction of fishways on coastal rivers in an effort to restore the migratory fish runs. Dams are an impediment to the fish migration, Nelson said, but "once the ladders were installed we had pretty good returns."
The Great Dam in Exeter was built primarily to power the local mills. According to Donald Clement, chairman of the Exeter Conservation Commission, over the years since the mills shut down the river has "cleaned itself up."
"Until 18 years ago you never even saw ice fishing shacks on the river. Now there are great smelt runs. Striped bass, which follow the river herring, now come right up to the falls," said Clement.
Understanding of a tightly wrought ecosystem is key to determining the causes of the decline in the numbers of herring making it over the dam.
According to Clement, such factors as the amount of water over the dam, water quality above the dam, increased sediment due to development and over-fishing are all possible contributors.
"No one can say if it�s any one of those or a combination," said Clement, "but a lot of people have a lot of concern. Have we lost a generation of fish? Did something happen to that fish stock fry (baby herring population)?"
Several possible causes - including a breach in the dam or problems with the ladder itself - have been ruled out.
Nelson also said it does not appear that the river herring are getting caught in the ocean. There is evidence of occasional alewife as by-catch due to trawling, but in no great numbers.
So concerned are fish and game officials by this trend that they held a hearing in Portsmouth to gather public comment on the proposed harvesting ban.
"I don�t want to give the impression that this is all because of fishermen. It�s just one consideration," said Nelson.
He added, "The other rivers seem to be doing well. We are not shutting off the ability to get bait in the estuary," but he said fishermen "may need to travel to one of the other rivers."
Nelson said a ban is only to encourage the return of the herring. "We�ll try to get more back to the river, then evaluate how successful we were this year. If thousands moved this year, if I saw 4,000, I would be very happy. We�d be comfortable."
Steven Courchesne, a fisherman from Hooksett, was one of the fishermen who attended the hearing. He said he has been harvesting river herring below the Great Dam the past five years. "I always catch my fish. I get my 300 pounds every year."
Courchesne and fellow fishermen said they see thousands of fish below the Exeter dam each year. "Tens of thousands of them," said Courchesne. "Schools of them as big as an acre."
Courchesne has volunteered his services to the fish and game department to catch herring and haul them over the dam. He said that in just a couple of hours, one man catching and two men hauling could transfer 4,000 fish.
"I�ve done it for the state in the past. We transferred freshwater smelt, going to New York, traveling four hours at night and fishing until 5 a.m. This would require very little effort compared to that. It�s 300 feet. If they want 4,000 fish over the dam, I�ll do it. I�m willing to help."
Nelson expressed reservation about department resources to support such an effort by the fishermen, but said he would discuss this proposal with his staff.
Nelson said many other factors affecting the lack of herring climbing the ladder are being studied.
The fish and game department is working with the town of Exeter to avoid unmanaged flows or discharge from the dam. Development in the area may also effect the riverbed and negatively impact spawning conditions.
(See part II of this series on Tuesday.)
The fishermen have requested that the department consider a restriction, rather than the proposed ban. Nelson said that he would take the suggestion under advisement, and the department would make a final decision by the end of April.
Courchesne said, "We only have 16 miles of coastline compared to all of the East Coast. Herring spawn up and down the entire East Coast and in to Albany - in every tributary. So what�s the big deal about this little river? I hate to see something taken away. I�ve seen things taken away by New Hampshire from sportsmen before, and never given back."
Coming Tuesday: A look at other factors contributing to the depleted herring stock.
# River herring - alewives and bluebacks - are anadromous fish, critical to both ocean and freshwater ecology.
# In saltwater, they provide food for larger species of fish such as striped bass, cod and pollock.
# Four- and 5-year-old adult river herring travel from saltwater to freshwater rivers from April to June to spawn and then return to the ocean.
# Juvenile river herring provide forage for freshwater species such as bass and trout as they migrate from August to October to the ocean.
# Humans harvest the herring as bait, primarily for lobstering
# Herring are also used as food and fertilizer.