EYE ON CONSERVATION
sinceyouasked
6 BirdWatchingLast year, the Roseate Tern population in
the United States reached its highest number
since 1987, when the northeastern U.S.
population was listed as Endangered under
the Endangered Species Act. According to
the Massachusetts Division of Fisheries and
Wildlife, the 2018 U.S. estimate was 4,552 pairs.
Canada had an estimated 51 pairs.
The rebound is due in large part to
successful habitat
restoration and predatory
gull management at
the birds’ three largest
breeding colonies, located
along the Atlantic coast
in Massachusetts and
New York. Living much of their lives on the
open ocean, Roseate Terns spend only a
few months on rocky islets, where they nest.
They winter off the northeast coast of South
America and in the Caribbean.
Overall, this population estimate is great
news, but Roseate Tern numbers remain short
of the recovery target goal of 5,000 pairs. And
in recent decades, encouraging increases have
been followed by declines; possible causes
include climate change, sea-level rise, loss of
food to commercial fishing fleets, and unknowndangers in the birds’ tropical wintering range.
A new threat is also growing: Offshore
wind energy development may provide a
collision or displacement hazard to the terns
and other seabirds. While the Block Island
Wind Farm in Rhode Island currently is the
only offshore wind facility operating in the
U.S., several other areas have already been
leased for development in southern New
England, including sites in
federal waters off the coast
of Massachusetts, Rhode
Island, and Long Island,
New York.
The majority of these
prospective wind-energy
projects fall within foraging areas used by
Roseate Terns before, during, and after the
breeding season. Confirming this hazard,
new tracking studies have documented
Roseate Terns crossing the areas designated
for wind-energy development. American
Bird Conservancy and other conservation
organizations are closely monitoring this
potential threat. We’re recommending that
projects not be sited in high-risk areas for terns
and that a mitigation fund be created to pay for
the population’s continued recovery.A
Q
Alc
ide
s^ MoralesA turn for the better
Julie Craves is an ecologist and the
retired director of the Rouge River
Bird Observatory in Dearborn,
Michigan. Read her blog at
http://net-results.blogspot.com.(continued on page 8)YOUR QUESTIONS
ANSWERED BY
BIRD BANDER
JULIE CRAVESAmerican Bird Conservancy is a 501(c)(3), not-for-profit organization whose mission is to conserve native birds and their habitats
throughout the Americas. Learn more about its work on wind energy at abcbirds.org/program/wind-energy-and-birds.RECOVERING: Record-high numbers of Endangered Roseate Terns nested in the U.S. in 2018.I volunteer at a national
wildlife refuge and always
see Burrowing Owls
standing outside their
burrows during the day,
then out hunting at night.
When do they sleep and
for how long? — Carolyn
Vance, Los Alamitos,
CaliforniaThe times and places that
birds sleep vary widely among
different bird families and
throughout the year. For
example, many diurnal
songbirds typically get most of
their sleep at night, as you might
expect. But if they are migratory
species that fly each leg of their
journeys overnight, they adjust
their sleep schedule and are
able to take multiple short naps
throughout the day, often each
less than 30 seconds.
Burrowing Owls, unlike many
owl species that are largely
nocturnal, are active both day
and night. However, they do
much of their hunting of large
insects and small rodents at
dawn and dusk. Studies have
found that after the food-
gathering episodes, Burrowing
Owls seem to prefer to get most
of their sleep just after sunrise or
in the middle of the night.
Sometimes the owls will sleep
near their burrows on a rock, low
branch, fence, or even in clumps
of vegetation during migration or
in winter. However, they
frequently sleep right next to
their burrow entrance. Not only