Sunday, April 25, 2010

The Mianus River Fish Ladder

I went to yesterday's open house at the Mianus River fish ladder, in Greenwich, and came away not just impressed but optimistic -- we're doing something right and, even though we're doing it to compensate for a couple of screw-ups, we deserve to take some satisfaction in it.

When I say "we," I mean we as a society, of course. The direct credit goes to the Town of Greenwich and its Conservation Commission and probably others whom I don't know (the state of Connecticut, maybe). The town built the fish ladder on the west side of the Mianus River dam, just above Route 1, as compensation for violations at its sewage treatment plant (that was one screw-up; the other was the dam itself). River herring -- alewives and blueback herring -- have used the Mianus to spawn for generations but once the dam was built, their progress upstream was stopped.

I learned yesterday that in typical years when there was plenty of fresh water coming down stream, some herring were able to spawn near the base of the dam; but in years of low flow, when salt water crept up from the lower part of the river and Long Island Sound, the salt made spawning impossible. I also learned, via Terry Backer on Facebook, that at some point in the past, people used to carry buckets of herring over the dam to help them spawn. I have a photo in my book, from the 1980s, of men scooping up herring from the base of the dam to use as bait.

The fish ladder gives the fish a free passage and from the evidence yesterday, they're using it. Each time Michael Aurelia, of the Conservation Commission, dipped his net into the passage, it emerged with three or four alewives. Thus far this year, the electronic fish counter has recorded 48,000 fish ascending the ladder -- a number the sounds nice and big except that when you're standing there and realize how big the river is, you could easily envision 48,000 fish a day ascending the river. A couple of times in the past three or four years, about 100,000 fish made it over the dam. Spawning season ends in mid-June, when the blueback herring run peters out, so there still may be time to approach that total this year.

Clearly, in an era when the number of spawning fish has dwindled to the point where it's illegal to catch alewives, blueback herring and (in New York at least) shad, the ladder is a good thing. The state of Connecticut has helped communities along the Sound build almost four dozen similar fish passages on other rivers, and Save the Sound recently helped install a new, wider culvert to allow more fish to ascend Bride Brook, in East Lyme.

It's all good. Congratulations.


Post a Comment

<< Home

eXTReMe Tracker