The nesting concentration of Common Terns on Great Gull Island (9500 pairs) is the largest in the world and the nesting concentration of Roseate Terns (estimate 1500 pairs) is the largest in the western hemisphere. Numbers of both species of terns
nesting on Great Gull Island are representative of coastal colonies. Changes in
these numbers over time alert us as to whether or not the coastal populations
are expanding, contracting, or holding their own, information critical for
management measures for both species. This is just one aspect of the work we do
on the island. I will touch on other aspects in the following report.
The 2012 season presented us with a number of firsts! For
the first time since we began working on Great Gull Island in 1969 we have
begun a program for controlling invasive plants which I think will work and
will result in increases in nesting by both Common and Roseate Terns. Thanks to
funding obtained from the Long Island Sound Future’s fund by Juliana Barrett,
UConn Sea grant program, to manage invasives on Great Gull Island, we began a
multi-year program of spraying and search for species of plants which will hold
the soil in some areas, but not spread at a rapid rate.
Suzanne Peyton of the USFWS is licensed to oversee spraying and
was on Gull Island April 19, 2012 to supervise the operation undertaken by
David Roach, general manager of All Habitats Services. In 2011 Suzanne
contributed ground cover and funded students from URI to come to Gull to put
the ground cover down. The ground cover worked well and was still in place in
2012 helping to keep areas open for terns.
During the time the Argentineans are on the island they
usually have construction projects which improve our facilities considerably.
This year they painted the stairs to the tower with wood preservative, the
rungs of the ladder in the tower with Rust-Oleum; Pablo Rojas and Marcelo
Sanchez Paressi built housing for the generators and stoves. The roof of the
housing for the generators was particularly colorful with shingles made from cans.
Dick Young and Loretta Stillman trapped in the area behind
the headquarters building. Their area was representative of the hatch in the
colony, providing excellent data on the beginning and end of the peak hatch as
well as subsequent hatching during the season.
From the last week in June through the last week in July we
had different crews of volunteers to help each week, many of whom were
recruited by Suzanne Peyton from students at URI and interns in the USFWS. All
were great workers and we would not have been able to accomplish what we did
during July without their help. In mid-July, student-intern Anya Auerbach took this
excellent picture of a Carolina Hawk Moth feeding.
At the end of July I was very pleased that Steve Quinn,
Senior Project Manager in the Department of Exhibition at the American Museum
of Natural History, his daughter Claire, and friend Sean Murtha with his son
Brendan came to Great Gull Island to help. At the time they arrived they easily
trapped the few nests that hatched during the first two days of their stay, and
then, since the work dropped off dramatically, they sketched the terns and
painted views of the island from blinds overlooking the fort and the nesting
areas. Sean wrote a little about their stay on his blog (seanmurthaart.com). During
this period many of the student interns on the island worked on trap repair and
some took very good pictures of the terns. Ian Putnam, a student from New Jersey, spotted a Harbor Seal at the eastern end of the island
that was tagged. He asked Anya to go to the eastern end of the island to try to
get a picture of the tag and the number on it. Anya’s picture was very clear.
I learned from Keith Macassa of the University of New
England’s Marine Animal Rescue and Preservation Center in Maine, the seal
pictured above was found on July 7, 2011 in Two Lights State Park, Maine. At
the time it was underweight, weighing 8.6 Kg. The animal had lacerations on its
flippers and was 80 cm. in length. They placed the seal in rehab and estimated it
was four to five weeks old. In the wild, seals are independent when they are
three weeks old. Rehabilitators released this seal January 18, 2012 in Bracy
Cove, Bar Harbor, Maine. By this time it measured 91 cm and weighed 21.35 Kg. On
July 21, 2012 Ian Putnam resighted the rehabilitated tagged seal on Great Gull
Island, New York and both Anya and Ian took pictures
Four tour groups visited Gull Island July/August: one from
the American Museum of Natural History, another from the Quebec Labrador
Foundation, a third included a number of members from different Connecticut
Audubon Societies; members of the Fishers Island Museum joined us the second
week in August.
At the end of the season there are fewer adult terns in the Great
Gull Island colony to guard it and predation by gulls increases. Melinda
Billings, a volunteer, was in the right place at the right time to document a Great
Black-backed Gull take a young tern the third week in August. Later in the week
Melinda took pictures of Harbor and Gray seals on the rocks near the island. A
few years ago we began to see perhaps one Harbor seal near the island
throughout the summer and in 2010 heard the haunting call of the Gray Seals, a
call that was sometimes hard to distinguish from the fog horn on Little Gull. In
2012 it was not unusual to see nine Gray Seals at the eastern end of the island
throughout the summer as well as at least two Harbor Seals on the north side of
the island. We tried calling the Gray Seals by imitating the sounds they made and
it seemed to work. They would approach us, rise out of the water to have a
better look and then slip away. On the evening Melinda took these pictures one of
the Harbor Seals on the rocks was not a bit camera shy and assumed a number of
poses the evening she photographed.
In addition to Roseate check Catherine planned and cooked most
of the meals during her time on the island. At the end of the season the
cooking mantle was passed to Melissa McClure during the last week in July and
again for a week August 16-23, which was very nice for everyone.
I was very pleased Dale Dancis, Nancy Stevens, Doug Kopsco and
Melinda Billings were willing and able to come to the island and help with the
field work, packing and cleaning at the end of the season. It meant that we
were able to follow the terns on Great Gull Island through Labor Day. Since there
were still young on the island that could not fly late in the season and over
1500 adults and young were still coming in to the island on a daily basis I was
glad we were able to do this. During the last days we were on the island 200-300
Common and Roseate Terns gathered on the new dock throughout the day. On
September 1 a Forster’s Tern and nine Black Terns joined the terns and a
Herring Gull gathered on the dock. A young Roseate Tern was still being fed in
the rocks near the dock when we left on September 4. People often ask if these
late hatchlings survive. We will be able to answer this question in more detail
shortly, but a quick look at banding dates of young that have returned to Great
Gull Island to nest shows that some young banded late in the season have
returned.
Finally, I am happy to report that Joe DiCostanzo, who has been in charge of computerizing the Common Tern data collected over forty four years, gave a copy of the data to population biologist, Robert Rockwell, who works across the hall from us in the museum. There are many questions to be answered and I am delighted that we will be working with Rocky on analysis of banding and recovery data for the Great Gull Island colony during the winter of 2012-2013.
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