"The Atlantic Sturgeon"
Sydney M. Williams
swtotd.blogspot.com
Essays from Essex
“The Atlantic Sturgeon”
May 18, 2017
“Atlantic
sturgeon didn’t make it for 70 million years without being resilient.”
Ted Williams
“Yale Environment 360”
Published by Yale School of
Forestry and Environmental Studies
February 12, 2015
A recent talk: “A Connecticut
River Mystery Revealed,” given by Kimberly Damon-Randall, a naturalist and
administrator with NOAA (National Oceanic and Atmospheric Administration), at
Essex Meadows. The subject: the Atlantic sturgeon, an ancient fish recently
returned to the Connecticut River. The meeting was sponsored by the Roger Tory
Peterson Estuary Center (RTPEC), on whose board I serve.
An old saying has it that they can kill you, but they can’t eat you. Of
course, a fish that is killed is usually eaten. The Atlantic Sturgeon is desired,
especially, for its eggs (caviar, or black gold, as they are known). The
species is still with us, but man’s rapacity over the past century severely
limited its numbers. Fortunately, the fish was added to the Endangered Species
Act in 2012, and is now making a come-back. However, as Ted Williams wrote in
the article quoted above, the Atlantic sturgeon has been around for tens of
millions of years, joining an exclusive club comprised of species like the
Horseshoe Crab and the Jelly Fish. It has learned to adapt. It survived the
intense heat of the Dinosaur age, when temperatures averaged 20% above today’s,
and higher. They made it through the ice age, which covered most of North
America, Europe and Asia with several hundred feet of ice. They survived the
six-mile-wide Chicxulub asteroid, which hit the Yucatan Peninsula about sixty
million years ago. Could man, with the advantages of a brain that reasons and a
mind that creates, have survived such devastation and extreme temperature
changes? Given the dynamic earth on which we live, someday we will surely find
out. Nevertheless, the Atlantic sturgeon adapted, when most other animals, with
whom they lived during the Mesozoic Era, did not.
The Atlantic sturgeon is primitive looking. Instead of having scales,
it has five rows of bony plates, known as scutes. Its life-span is about sixty
years. At maturity, which is achieved between fifteen and twenty years, a female
can weigh up to 800 pounds and be fifteen feet in length, an unusual sight in
the estuary of the Connecticut River. The fish is anadromous, which means it
migrates from salt water to spawn in fresh water, as do salmon, shad and
striped bass. The Atlantic sturgeon has an elongated snout, which
differentiates it from its smaller, (and more common) cousin, the Snub Nose
sturgeon. They are toothless, benthic omnivores. With a tube-like mouth located
on the underside of the head, which extends several inches when feeding, it
vacuums up insects, worms, clams and mussels from sea and river beds. Four
barbels, which could be mistaken for fangs, but are in fact taste buds, dangle
from their upper lip. Like many of nature’s creatures, they are camouflaged.
Seen from above their brown coloring blends with the sea or river bottom, while
their white belly, when viewed from below merges into the sky.
In early North America, Atlantic sturgeon were seen, as a nuisance as
their rough skin would rip open fishing nets; but soon they became profitable –
one of the first “cash crops” to be harvested in Jamestown, Virginia. Their
exterior was used in clothing, bookbinding and as isinglass. By the late 19th
Century, they were heavily fished for their eggs and flesh. Up to seven million
pounds of sturgeon meat were exported annually in the last decade of the 19th
Century. But, overfishing caused a sharp decline; exports declined to 22,000
pounds in 1920.
Their decline was precipitous; only gradually have they made a come-back.
According to the NMFS (National Marine Fisheries Service), in the late 19th
Century 180,000 “ripe” females entered the Delaware River (then known as the
caviar capital of North America). Today, the agency estimates there are less
than a hundred. Females reach sexual maturity about age sixteen and lay eggs
every three to five years, so populations will rebound, albeit slowly.
Humans almost eradicated these fish a hundred years ago, and now humans are
leading conservation efforts to restore them. It is their return to the
Connecticut River that I find exciting. Three years ago, the remains of a
seven-foot, 100-pound immature female was found about five miles up the River,
near the entrance to Hamburg Cove. In the same year (2014), a few pre-migratory
juvenile specimens (estimated to have been hatched in 2013) were collected. DNA
testing suggested that a small number of families – perhaps eleven – produced
the off-spring. The fish found in 2014, according to the Connecticut Department
of Energy and Environmental (DEEP), were too small to have emigrated from other
systems, so scientists felt certain they were hatched in the Connecticut River.
It had been decades since such findings had been confirmed. Acoustic
transmitters were implanted into a few larger fish, so their movements can be
tracked.
Spawning occurs in flowing waters, just beyond where the salt front,
the leading edge of seawater, and the fall line of large, fresh-water rivers
come together – often near where dams have been built. A female can lay between
400,000 and eight million eggs. Maximum fertility is reached at around 30 years
of age. As a father of three children, that seems like a lot of kids, but, keep
in mind, only a small percentage make it to adulthood. Eggs are easily
destroyed and the young serve as food for other species. As they get larger,
and less appetizing to natural predators, survival probabilities increase. Besides
man, not only as a fisherman but as a dredger and blaster of rock ledge, the natural
prey to mature Atlantic sturgeons include killer whales, sharks and seals.
Generally, man operates in his own self-interest. In bygone times, and
in primitive societies today, man did what he must to survive. Some of what he
did was antithetical to modern concepts of conservation. However, we must keep
in mind that conservation is a consequence of education and wealth. The first
allows us to better know, understand and appreciate our environment, while the
second provides the funds necessary to preserve and conserve what we have
inherited. (In terms of education, the RTPEC now instructs over 800 school
children in our region on the basics of environmental stewardship.) We have
come a long way in the past 150 years. Rivers are cleaner than they were, as is
the air. About 85 million acres (3.5% of our land mass) is in national parks,
with another 15 million acres protected in land trusts. There remains work to
be done, but we must balance the needs of myriad segments of our society, so
that the path we travel permits economic growth and conservation. Taken
under our wings, to mix my metaphors, the Atlantic sturgeon should survive. I
hope so, for it gives our children and grandchildren the opportunity to witness
a species that lived during the time of the dinosaurs, a fascinating fact and
indicative of a remarkable resiliency. There is much we can learn from its adaptability
to changing environmental conditions over many millennia.
Labels: Atlantic sturgeon, Conservation, Environmental, Essays from Essex, Fish
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