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For alewife, life's journey now a little easier

East Lyme - As the tidal waters poured out of Bride Brook into Long Island Sound Friday, schools of alewife somewhere in the Sound swam toward the stream, preparing for their nighttime passage from saline to fresh water.

The stream winds through Rocky Neck State Park before opening to the Sound in a channel across the beach. From a footbridge over the stream, Gwen Macdonald scanned the waters for the silvery fish. She had hoped to see them while the sun was high. But on Friday, they seemed to be waiting for evening to swim into the brook, apparently oblivious that a daytime appearance on Earth Day would have cheered some onlookers.

No matter, though. Macdonald, director of habitat restoration for the Save the Sound program of the Connecticut Fund for the Environment, already knew this is a strong year for the annual run of alewife, one of two species of river herring but the only one that uses Bride Brook. She had no reason to doubt that the project her group spearheaded two years ago - replacing a rusted, sand-clogged culvert for the brook with a wide box culvert and riprap - was doing the trick.

"The new culvert size has allowed more fish to come up in one night," she said.

Last Tuesday, after the first two to three weeks of this spring's run, 118,845 alewives had already swum into Bride Brook, continuing through the salt marshes upstream and eventually reaching the fresh waters of Bride Lake, where they will spawn.

Steve Gephard, supervising fisheries biologist for the state Department of Environmental Protection, got that number from the DEP's fish counter at the place where the lake empties into the stream. The run, which started earlier than at other rivers and streams, is the second-largest alewife run in the state after the Connecticut River. More schools of 6- to 8-inch adult alewives will migrate into Bride Brook during the next four to six weeks.

"Obviously it's going to be a good year," Gephard wrote in an email message.

Last year, the first for the new culvert, 164,139 alewives were counted entering Bride Lake for the entire run. The year before, the total was 74,839.

Gephard said there are normal year-to-year variations in the totals, so the jump from 2009 to 2010 can't be solely attributed to the new culvert. Last year alewife numbers all over the state were high compared with other recent years, he added. But had the Bride Brook passage not been rebuilt, "the old pipes would have collapsed and no fish would have gone to the lake to spawn."

The new culvert surely allows larger schools to pass through at once, he added. A peak night for the old culvert would have been 5,000 to 8,000 fish. Now, 20,000 can get through in a single night.

"Getting them in sooner and spawning earlier, and the juveniles going out to sea sooner may have some long-term benefits to the health of the run," he said.

Seed stock

Macdonald said the Bride Brook run is important not only for the numbers of alewives, but also because this population provides the seed stock for restoration efforts elsewhere in the state. Pregnant female herring from Bride Brook were transplanted last year to the Rippowam/Mill River in Stamford after a dam removal project, and again this year to the Noroton River in Darien after a Save the Sound project.

Populations of both alewife and blueback herring have declined in recent decades compared to historic numbers, and harvesting them for bait and other purposes has been banned since 2002. Because both species of river herring are critical parts of the ecosystem, providing an important food for larger fish, wading birds and other animals, many recent projects by state, federal and private nonprofit groups have focused on trying to restore river herring.

But the benefits of the culvert project go beyond the herring, Macdonald said.

The project, paid for with more than $500,000 in grants from state, federal other sources, included planting native grasses and shrubs to secure the dunes around the culvert. The last 10,000 plants were set just three weeks ago by a band of volunteers that included U.S. Sen. Richard Blumenthal, D-Conn., U.S. Rep. Joe Courtney, D-2nd District, and DEP Commissioner Daniel Esty.

Ongoing monitoring of the salt marsh upstream, Macdonald added, is showing that native marsh grasses are re-vegetating areas once inhabited by invasive reeds. The new culvert, she said, allows more saltwater into the marsh to mix with the fresh water from the brook, and that benefits the native plants.

"Before, it wasn't getting enough tidal flushing," she said.


An underwater look at the alewives in Bride Brook


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