A lot of the fish that, in one way or another, are important
to anglers in New England and the Mid-Atlantic are what biologists call “diadromous,”fish that must travel between salt and fresh waters as part of theirreproductive strategy.
Striped bass are the first such fish that comes to mind, for
as we all know, while they spend most of their lives in salt water, every
spring they run up certain rivers, including the Hudson, Delaware and various
tributaries of Chesapeake Bay, in order to spawn.
If the bass are to spawn successfully, the water that they
spawn in must have certain characteristics.
The
most recent benchmark stock assessment states that
“Striped bass spawning areas are characteristically turbid and
fresh, with significant current velocities due to normal fluvial transport or
tidal action…
“Striped bass spawn at temperatures between 10 and 23oC,
but seldom at temperatures below 13 to 14oC. Peak
spawning activity occurs at about 18oC and declines rapidly
thereafter…
“Newly hatched bass larvae remain in fresh or slightly brackish
water until they are about 12 to 15 mm long. At that time, they move
in small schools toward shallow protected shorelines, where they remain until
fall. Over the winter, the young concentrate in deep water of
rivers. Those nursery grounds appear to include that part of the
estuarine zone with salinities less than 3.2o/oo.”
A river that lacks such
characteristics won’t be able to support striped bass reproduction.
Yet even if a river contains suitable striped bass spawning
grounds, the bass might not be able to reach them. Ever since European settlers arrived in North
America, they have been building dams and creating impoundments for various
purposes, often to power grist mills or, later, other industrial
enterprises. Such dams alter the basic
characteristics of rivers, and deny fish access to spawning grounds.
However, dams can be removed, and dams fail. The removal of failing, no longer needed dams
can, in the end, be the most cost-effective solution to both fishery and
watershed issues.
Maine’s Kennebec River historically supported a small
spawning population of striped bass. Construction
of the Edwards Dam in the 1837, and the resultant industrial activity, degraded
the river and ultimately destroyed its native striped bass spawning population. Striped bass from New York were later
reintroduced in the river, and a spawning population, that struggled to survive
below the dam, was restored. However,
that population’s future wasn’t assured until 1999, after the Federal Energy
Regulatory Commission refused to renew the dam’s hydropower license due to its
negative impact on fisheries, and the dam was removed.
Such
removal gave the striped bass access to just about all of their historic
spawning grounds, and led to a marked increase in both the spawning population
and in striped bass abundance in adjacent ocean waters. It provided a
model for additional dam removals on every coast of the United States.
Striped bass are not the only fish that benefit from dam
removal, and not the only diadromous fish important to striped bass
anglers.
Not too many years ago, the run of river herring—a collective
term that includes both alewives and river herring—into northeastern rivers
heralded the first good striped bass bite of the year. Whether you just called them “herring,” as we
did in Connecticut, or “buckeyes”
up in Massachusetts, the silver shoals of river herring running upstream
brought stripers with them. Anglers
fishing from sod banks and shorelines, and boaters in the estuaries, caught
more than their share of striped bass either livelining herring or fishing
herring-imitating lures.
As dams clogged the herring’s natal streams, the runsdeclined, and in most places, river herring can no longer be caught for use as bait,
and bass no longer clog river mouths in pursuit of a baitfish that is no longer
there.
Yet, once again, there is hope. On many rivers, old, obsolete dams are being
removed, and when dams must, for whatever reason, remain in place, more and
more state and municipal governments are installing fishways that allow herring
to get around the dams and continue their swim upstream.
The state allowed the fishways to reopen in
2013, and in just the few years since, the river’s alewife run has swollen from
just 900 returning fish to about half a million. That’s a big increase, but is still just 5%
of the river’s possible carrying capacity, so there’s still a long way to
go.
And then there are eels.
Eels don’t trigger striped bass blitzes, but they are one of the striped
bass fishermen’s favorite baits. And they are in trouble, with dams
and loss of access to upstream habitat one of the factors in their decline. While the American eel population is
suffering from a number of causes, there is little doubt that better access to
upstream waters, where females spend almost all of their adult lives (males
tend to remain in estuaries and the rivers’ lower reaches) would alleviate one
stress on the population, and so impact eel abundance.
Then there are the species that anglers don’t even think
about anymore.
During the Colonial period, Atlantic salmon were present in
most, if not all, major New England rivers, until dams and pollution denied
them access to upstream spawning grounds.
Now, they only maintain a tenuous hold in a few Maine rivers, and all
of Maine’s salmon runs are listed under the Endangered Species Act. Yet there are signs that even the salmon will
respond to improved upstream access.
On
Maine’s Penobscot River, dams have been removed, making Milford Dam the first
obstacle to the salmon’s upstream passage.
And a fish lift installed at Milford Dam helps keep the salmon swimming
upstream. Just a few days ago, on June 20,
107 salmon, an all-time record number, were captured at the fish lift and
helped on their travels upstream. Given
that only about 750 fish migrated up the Penobscot in all of 2018, seeing
107 salmon in a single day was very good news.
While biologists
believe that it will take 75 years to get Maine’s Atlantic salmon off the
Endangered Species List, this year’s run at Milford, at the least, gives
reason to hope that delisting might, one day, occur.
A
number of other species, ranging from tiny rainbow smelt and sea-run “salter” brook
trout to the
huge Atlantic sturgeon, have been hurt by dammed rivers, and benefit when
dams are removed.
So far, I’ve written about good things happening with fish passage
in Maine, but readers should rest assured that opportunities for dam removal
and other fish passage improvements exist in just about every coastal state.
Anyone who cares about maintaining and
increasing native populations of diadromous fish need only do a little
research, perhaps contacting organizations such as Trout Unlimited, American Rivers or
local conservation groups, and see what they can do to help out their home waters.
Having said that, I’ll close with a message to my fellow Long
Islanders.
Sometimes, opportunities for improving fish passage don’t
involve years of work and planning.
Sometimes, they drop into your lap.
That has just happened out in Oakdale, where some
old, watersoaked boards in a weir on West Brook have recently rotted through
and collapsed, draining the impoundment behind the low dam and allowing the
river to resume something resembling its natural course. If you ever drive east on Sunrise Highway you
know the place; West Brook drains out of Connetquot State Park just west of the
park entrance and, until the weir collapsed, backed up into the shallow, warm, weed-choked
swan pond that spread out just south of the road.
The State Parks is considering rebuilding the
weir, and flooding the pond’s basin again; a fish ladder might be a part of any
such rebuild, but no fish ladder functions as well as a free-flowing
stream.
Undammed, West Brook could again host spawning runs of river herring,
and would be more attractive to eels. If
the flow could be effectively maintained, and water temperatures kept
appropriately cool, there is even a chance--perhaps remote, but a chance--that it might again host a small
population of native brook trout.
Dammed, it will again be a warm, weedy, shallow pond that
might host a few eels, and whatever alewives manage to get around the new
weir, but it will not be anything resembling a healthy river, and will not provide
habitat for the same species that require a cooler waters and steadier flow.
Thus, I’m asking that you take a few minutes to contact
George Gorman, Long Island Regional
Director
New York State Office of Parks and
Recreation
625 Belmont Avenue
West Babylon, NY 11704
(631) 669-1000
and tell him that the best way to save taxpayer dollars that would otherwise be spent on
dam and pond maintenance, and more importantly, to preserve native habitat and
native species, is to let West Brook run free.
Thank you.
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