Fish Ladders News Roundup!

February 11, 2015 0 Comment(s) Animal Ladders, Fish Ladders,
There has been a lot going on in the world of fish ladders lately and it’s all good news An alewife herring against a white background.for herrings (and people who like to eat them!).  The alewife species of herring is native to North America, but as with all types of fish, man-made obstacles in the rivers have seen the population decline in the last fifty or so years.  Even when there are fish ladders in place there can still be a decline in population, as the fish ladders can fall into disrepair and older types are not as efficient as newer designs.At the Nequasset Dam in Maine the fish ladder had been in place for nearly sixty years.  Built in 1955, the concrete structure was in need of repair after years of exposure to cold water and freezing conditions so Bath Water District, which owns the dam and fish ladder has teamed up with Kennebec Estuary Land Trust, the Woolwich Fish Commission and other agencies to design and build a new one.The new ladder is being constructed at the moment, and should be operational by next spring, when the alewives begin their migratory journey back to the spawning grounds.  Atlantic Mechanical Inc. won the bid to demolish and rebuild the fish ladder, and they are based in the area, meaning that the projects has stayed local and enhanced the economy of the area, as well as the environment.  It is hoped that the new dam will help restore the numbers back to at least the 2012 levels of 164,000 fish over the ladder, compared to just 19,061 this year.Nearby in Rochester, Massachusetts, alewives are also being helped by the donation of $10,000 to the area’s largest cranberry grower, Douglas Beaton.  Beaton owns 55 acres of cranberry growing bogs, fed by water from the Sippican River that flows into Hathaway pond over the dam.  Beaton’s land also drains into Hathaway pond, and he relies on the local watercourse to provide irrigation for his crop, having received land rights to the pond as part of the purchase of the growing land.  The rights require him to maintain and repair the dam, so the donated money will go a long way to helping pay for improvements that benefit the migrating alewives.A view across to the Whitehorse DamThere’s also good news for the Chinook salmon in Canada.  This year the number of fish navigating the river and returning to their natural spawning grounds has been above the minimum set out in a treaty between the USA and Canada.  42,000 salmon must make it to the spawning grounds according to the terms of the treaty, and the major factor behind this increase has been a total ban on fishing on the Yukon River, something that a local fish hatchery manager is amazed by.  Lawrence Vano, who runs the hatchery at the Whitehorse Dam, congratulated the abstinent anglers saying, “I never, ever would have thought that they would actually agree to not fishing for at least a season…at least it is a starting point.”It’s certainly good news on the surface, as clearly the fish ladders in the area are working.  However, the number of hatchery-raised fish returning to the spawning grounds far outnumbers the amount of wild fish making the journey.  On top of this, males outnumber females by three-to-one, meaning that the majority of fish returning won’t be able to breed.  Vano hopes to be able to redress the balance with fish raised in his hatchery and that in five years when the spawning salmon return again there will be sufficient stock to keep the population high.

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