After record lows, herring stock is now healthier, living longer 5-4-14
After record lows, herring stock is now healthier, living longer
Cape Cod Times
By Doug Fraser
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May 04, 2014
EASTHAM — Bill Allan leaned against a chain-link fence and peered into the rushing water below.
He held a length of string connected to a thermometer that was obscured by the clouds of champagne bubbles from water spilling out of Bridge Pond, sliding over a thick wooden gate and collapsing into the stream below.
Off in a corner, huddled away from the force of the water shooting downstream, and the big bass that had accidentally slipped over the spillway and into the run, was a bluish gray ball of alewives gathering up energy for that last push into the pond where they could spawn.
Allan is one of 26 volunteer herring counters who each take a 10-minute shift for the 12 hours between 7 a.m. and 7 p.m. every day at Cole Brook. Its recently restored herring run, including two new concrete culverts, was installed last year and is the newest addition to a network of 14 Cape streams and rivers overseen by the Association to Preserve Cape Cod.
Following protocol, Allan only counted the fish that made it up over the final gate and into Bridge Pond. Observer numbers would eventually get entered into a formula that computed an estimate of how many alewives reached the pond every day, along with environmental data like water temperature.
The association started doing official counts with three runs in 2007, adding more locations yearly, hoping its data will help scientists and fishery managers bring alewives and blueback herring, known collectively as river herring, back from a disastrous coastwide collapse nearly a decade ago. Some big picture guys like Michael Armstrong, the state Division of Marine Fisheries assistant director for fisheries biology, see positive signs of progress.
"Our good runs are our bellwethers," Armstrong said.
In the state's four largest herring runs, including the Monument River on the Cape Cod Canal in Bourne, the numbers of fish have been increasing each year over the past three or four years to the point where the state is considering how they might allow some harvesting of river herring at those runs while still enforcing a harvest moratorium elsewhere that has been in effect since 2006. Additionally, herring sizes are up slightly as is the number of older fish, meaning the stock is healthier and living longer.
But that doesn't mean these fish, which are born in freshwater ponds and lakes and spend most of their lives in the ocean, are out of the woods.
"We're looking at the numbers, but they are still so low compared to where they are felt to have been historically," said association senior scientist Jo Ann Muramoto.
Individual streams could show big changes from year-to-year, but a big year is just as likely to be followed by a poor one.
"In the big picture, we'd have to see a lot more increases for a longer period of time," Muramoto said.
'SIGN OF SPRING'
Scientists are also not sure why these fish stocks collapsed back in 2005. With habitat that straddles both the land and the sea, the answers are much more complicated than simply blaming it on overfishing. Until recently, there was little funding for research into a fish that had little commercial value.
The Cape has 40 herring runs, the state around 100. Thirty-three runs are monitored statewide, and 10 of those have accurate video or electronic counters, Armstrong said. Allan compared herring to salmon that also brave the perils of the open sea, only to run into a gauntlet of predators and the endurance test of current and obstructions each spring to reach their natal home.
"I think herring are way cooler than salmon," said Abigail Archer, marine resource specialist at the Cape Cod Cooperative Extension and a coordinator for the River Herring Network. Unlike salmon, river herring do not generally die after mating, but have to muster the energy for a return trip every year for three or four years.
"It's a sign of spring, and it's a way the ocean is connected to the land," Archer said. "These fish survive the whole winter, roaming the Gulf of Maine, and they find their way home every year. It's consistent."
So mysterious, so fecund, so dependable, river herring were pretty much taken for granted for centuries. Fishermen caught 8 million to 12 million pounds a year through the 1960s, sometimes for food, but most often to be used for bait and fertilizer. The species had been in a long slow decline, but that consistency faltered big time about a decade ago. All along the Atlantic coastline, once prolific runs recorded record low numbers, or none at all. Extinction warning bells started going off.
"People got frightened when they didn't show up," Archer said. It was easy to find volunteers to count the Cole Brook herring, said count coordinator Ivan Ace, who quickly recruited more than two dozen.
"It was quite incredible. It was almost like people were waiting in the wings to do it," Ace said.
threats to herring
In 2006, Massachusetts enacted a moratorium on catching river herring, as did three other Atlantic coastal states. In 2011, the Natural Resources Defense Council petitioned the National Marine Fisheries Service to list the river herring as threatened under the Endangered Species Act.
A fish that inhabits both inland and offshore waters has many potential problem areas, making it harder to bring them back. Overfishing, habitat and water quality degradation, the rise of predators like striped bass, dogfish and seals, and an industrial scale Atlantic herring fishery that uses large vessels towing enormous nets that can also snare river herring, all came under scrutiny as possible culprits.
After years of lobbying and litigation by local fishermen and environmental groups, the fisheries service and the New England Fishery Management Council are considering regulations to make sure the offshore herring fleet isn't also catching river herring, but the majority of their runs remain dammed or neglected. A 2001-2002 survey looked at 215 Massachusetts coastal waterways and found 380 blockages, including dams, that kept fish from spawning grounds. The same survey found that almost half the 175 structures intended to get fish past dams were not functioning.
There are 2 million dams blocking 600,000 miles of river nationwide. The National Oceanic and Atmospheric Administration has removed 90 dams, improving 1,700 miles of habitat, including some in Massachusetts.
There may be other answers to why the herring crashed. Years of big decline, like 2005 and 2007, coincided with heavy droughts and low water levels in ponds, rivers and streams. That made it hard for the juveniles to get past obstructions like dams with little or no water flowing over them in the summer months to carry them back to the sea. While the juveniles did stay in the ponds, they are usually weaker because of limited food supply, if they survive at all, Armstrong said.
He also believed the rise of striped bass, a major predator of herring, may also have played a role. Before the spectacular comeback of striped bass, the Connecticut River averaged 400,000 river herring, but now averages 40,000.
"That completely coincided with the rise of striped bass," Armstrong said.
RESTORATION PROJECTS GETTING MONEY
But Armstrong sees some evidence herring may be turning a corner. The state's four major runs are all consistently stronger than the low point in 2005. The Nemasket River in Middleboro, for instance, averaged around 910,000 fish per year before 2002, peaked at 1.9 million fish then crashed to 410,000 fish in 2005. Beginning in 2008, those numbers rebounded to around 791,000 fish per year on average.
The state also has a fishways department that works on repairing and replacing runs, and Armstrong said scientists know a lot more now than they did seven or eight years ago.
The state samples around 50 percent of what the Atlantic herring fleet offloads at Massachusetts ports and it finds very little river herring, Armstrong said. Thanks to money generated by the state's saltwater fishing license for recreational fishermen, the Division of Marine Fisheries hired three biologists to work on river herring. Genetic and tagging studies are underway to help determine where river herring go when they leave the inland waterways, how much they mingle with Atlantic herring, and whether it's possible that fluctuations in returning fish to any one location may be the result of a single tow that captures most of the fish from a particular stream as they school together.
In the nine years since the population crash and the moratorium, river herring have ascended to the spotlight. Always hard to come by, money started to flow toward restoration projects. In Brewster, for example, NOAA spent $1.67 million to widen a culvert from 3 feet to 18 feet on Paines Creek, which feeds the historic Stony Brook herring run. Last year, the feds approved spending $7.5 million to replace a culvert in Chatham and Harwich, and another in Yarmouth with improved fish passage and habitat playing important roles in obtaining the money.
His part in this cycle of life is extremely gratifying, said Eastham public works Superintendent Neil Andres, whose crew recently installed the two new culverts on Cole Brook thanks to a $124,325 grant from the U.S. Department of Agriculture. They also fixed some road drainage problems at the same time.
"Any time you get stormwater issues and fish restoration, you can get funds," Andres said.
