Seal numbers in Narragansett Bay
reached a record high in March when an informal survey conducted by volunteers
from Save the Bay, the Environmental Protection Agency and the Narragansett BayNational Estuarine Research Reserve tallied 603 seals at 26 sites. The previous record of 569 seals was set in
2011.
Seals were observed in all parts of
the bay, including a single animal hauled out on a rock just off Fields Point
in Providence and 101 seals counted at Brenton Point in Newport. Participants
also counted large numbers of seals at Rome Point, Coddington Cove, Prudence
Island and Hope Island, each of which had more than three dozen seals in the
vicinity.
“High numbers of observed seals in
the water are a strong indicator of a hospitable environment and a healthy
ecosystem that provides sufficient food and other needs for marine life,” said
Eric Pfirrmann, the captain of the boat used by Save the Bay to count seals.
“We can attribute a strong seal population here to both a healthier bay and the
Marine Mammal Protection Act of 1972, which made it illegal to kill, take or
harass marine mammals.”
The seal survey has been conducted
annually since 1994, though ice and poor weather forced the cancellation of
last year’s survey. Almost all of the
animals counted were harbor seals, which have been proposed to be designated as
the state marine mammal of Rhode Island. A small number of gray seals were also
seen.
Pfirrmann said that despite the
record number of seals in the bay this year, seal numbers have remained
somewhat consistent in recent years.
“Seal populations fluctuate from
year to year, just as environmental conditions fluctuate,” said Pfirrmann. “I
feel the seal population has been relatively stable for some time now, and that
the bay is probably at carrying capacity for harbor seals.”
According to Robert Kenney, a marine
mammal expert at the University of Rhode Island’s Graduate School of Oceanography, harbor seals begin to arrive in Narragansett Bay in September,
reach a peak in March, and depart by the end of April. They all migrate north
to the coast of Maine and the Canadian Maritimes to breed, though a small
number give birth on the Isles of Shoals in New Hampshire and in Manomet,
Massachusetts.
Despite the record number of seals
observed in Narragansett Bay this year, Kenney said scientists suspect that the
New England harbor seal population may be declining.
“Stock assessment surveys hint that
numbers are down from their peak, maybe because they’re being pushed around by the
larger gray seals, which are growing like crazy,” Kenney said. Large numbers of
gray seals breed at Monomoy National Wildlife Refuge on Cape Cod.
Seals were quite rare in Rhode
Island waters prior to passage of the Marine Mammal Protection Act. The peak
number of seals observed at any one place in Narragansett Bay in the 1960s was
12 at Rome Point. At that time, Massachusetts and Maine paid a bounty of $5 for
every seal killed, because the animals were thought to be negatively affecting
the region’s commercial fishing industry.
“I remember hearing stories of
people who would go out on motorboats to shoot seals for fun,” said Kenney.
Despite the seemingly healthy
population of seals in Narragansett Bay today, little is known about their
ecology during the six months they spend in Rhode Island waters. Kenney said it is unknown what they eat while
they are in the state, so it’s impossible to determine whether there is enough
food to sustain them or whether the population can continue to grow.
One thing is certain, however. The
harbor seal population that winters in southern New England has been spreading
out in recent years, Kenney said. Rather than being confined to Narragansett
Bay, eastern Long Island and eastern Connecticut, they are now found as far
south as New Jersey.
“We really don’t know what component
of the population comes down this far,” Kenney said. “There has always been
some suspicion that harbor seals in our area tend to be younger animals. Maybe
the younger ones have a harder time coping with the really cold water to the
north.”
People interested in observing seals
should be careful not to disturb them.
“Anything that’s going to spook them
off the rocks is harmful to the seals because it makes them waste precious
energy,” said July Lewis, the volunteer manager at Save the Bay who organized
the seal survey. “So be careful not to let dogs bark at them. And if you’re
approaching them in a kayak or other boat, go parallel to the rocks so it
doesn’t look like you’re going straight at them, which they interpret as an
attack.”
“Even if you think you’re at a safe
distance,” she added, “if you see them stretching their necks or moving around,
you’re too close.”
This article first appeared on EcoRI.org on April 6, 2016.
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