Driving
north last week near my home in Rhode island, I saw an adult bald eagle eating a dead Canada goose in the
median of a major highway. Not long ago I would have slammed on my brakes
and turned around to get a better look at the majestic bird, but now bald eagle
sightings in southern New England in winter are almost commonplace.
Bald eagle photo by San Diego Zoo. |
It
hasn’t always been this way. According to Rachel Farrell, a member of the Rhode Island Avian Records Committee, bald eagles were fairly common winter residents
in Rhode Island prior to the 1960s, but they nearly disappeared from the state
for the next 30 years. A total of just two were observed during the annual
Christmas bird counts between 1962 and 1988. The decline was caused by the use
of the pesticide DDT, which made its way into lakes and ponds and accumulated
in the tissues of fish. When eagles ate the fish, the toxin caused reproductive
failure. As a result, bald eagle populations throughout North America crashed.
DDT
was banned in 1972, but it has taken a long time for the birds to rebound.
Ospreys, the fish-eating hawks that nest atop platforms on utility poles throughout
the region, were similarly affected by DDT, but they recovered their
populations much more quickly than have bald eagles. It took many years of work
by wildlife officials to relocate eagle chicks from other parts of the country
and place them with “foster parents” at the Quabbin Reservoir in Massachusetts
before the New England eagle population began to grow on its own.
Now
that a healthy wintering population of bald eagles has become re-established in
Rhode Island, some of the birds are sticking around to raise young here. A pair
has been nesting at the Scituate Reservoir for about a decade, and two or three
other nests have been discovered elsewhere in the state in the last two years,
though their precise locations are a well-kept secret to protect the birds from
disturbance.
As
exciting as it is to see bald eagles back in Rhode Island, one ornithologist
wonders if it’s an entirely positive development. University of Rhode Island Professor Peter Paton says that researchers have found that the large number of
bald eagles breeding in Maine are eating so many gulls, eiders and great
cormorants that populations of those birds are declining. And many of the
eiders and cormorants that summer in Maine spend their winter in coastal
southern New England. Which means that eagle predation in Maine may be causing
a decline in eider and cormorant numbers in Rhode Island.
But
I suspect that most Rhode Islanders would trade a few common water birds for a
bald eagle any day. And until those water birds look like they’re in trouble,
I’d make that trade, too.
This article first appeared in The Independent on January 21, 2016.
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