FALKNER ISLAND TERN PROJECT
Background and History
(Click here for background information on Roseate Terns)
Falkner Island is a 2-hectare (4.5-acre) crescent-shaped island located in Long Island Sound about 5 km (3 mi) south of
Guilford, New Haven Co., Connecticut at 41 degrees 13' N, 72 degrees 39' W. A detailed description of the island and its
recent history is given in the book The Island Called Faulkner's by Joel Helander. Since the 1960s, Falkner Island has been
the site of the largest Common Tern (Sterna hirundo ) and Roseate Tern (S. dougallii ) colony in Connecticut, and it is now
the site of the third-largest Roseate Tern colony in the northeastern U.S. (Click here for a picture of a Roseate Tern)
The tern colony at Falkner Island was visited irregularly in the early 1970s by people working in association with Helen Hays of
the American Museum of Natural History's Great Gull Island Project. After Fred Sibley and Jeff Spendelow visited the island
several times in 1977, they started the Falkner Island Tern Project (FITP) in 1978 and ran it jointly as a Common and Roseate
Tern banding project for three years. When Dr. Spendelow became the FITP's sole Director in 1981, he changed the focus of
the project to concentrate on Roseate Tern research due to concerns about the declining North Atlantic breeding population of
this species. Dr. Sarah W. Richards, President of Little Harbor Laboratory (LHL) in Guilford, ran the project from 1983-1985
when Dr. Spendelow moved to Louisiana to begin work for the U.S. Fish and Wildlife Service (FWS). After moving back
north to work at the FWS's Patuxent Wildlife Research Center (PWRC) in Laurel, Maryland in 1985, Dr. Spendelow resumed
actively directing the FITP fieldwork the following year. (Click here for a picture of a typical field day).
Ownership of Falkner Island was transferred from the U.S. Coast Guard to the FWS's Division of Refuges in 1985, and the
island then became part of what is now called the Stewart B. McKinney National Wildlife Refuge (NWR). Recognizing both
the need to build a strong partnership with state and local support, and the need to draw on outside expertise to help manage
and conserve the wildlife resources at Falkner Island, in 1986 the Division of Refuges and PWRC developed a Cooperative
Agreement between the FWS, the Connecticut Audubon Society (CAS), the Connecticut Chapter of The Nature Conservancy
(TNC), and LHL to provide both financial and logistic support for the FITP. In 1987, the Cooperative Agreement was
expanded to include the Connecticut Department of Environmental Protection (DEP), Dr. Spendelow became the coordinator
of a cooperative long-term study of the population dynamics and ecology of the Roseate Terns breeding in Massachusetts,
Connecticut, and New York as part of his official duties at PWRC, and at the end of the year the entire northeastern breeding
population was declared "Endangered" by the FWS.
In 1988, Dr. Spendelow was appointed Chairman of the Technical Working Group which advises the Northeastern Roseate
Tern Recovery Team (NRTRT), in 1993 he was transferred to the National Biological Service (NBS) when it was created by
bringing together most biological researchers from all the other agencies in the Department of the Interior, and in 1994 he was
appointed the NBS representative to the NRTRT and his "metapopulation" study was expanded to include the Roseate Terns
nesting at several other sites in the Massachusetts-New York area. Many of the research methods and the habitat modification
techniques for increasing the productivity of the Roseate Terns that have been developed by Dr. Spendelow and his
co-investigators as part of the FITP and/or the PWRC metapopulation study are now being used at other tern colony sites in
the U.S. and Europe.
Current FITP Activities
In addition to the Dr. Spendelow, the FITP staff usually consists each summer of a PWRC Biological Technician and 4 or 5
Research Assistants hired as employees of the CAS. FITP staff members work staggered schedules so that usually only 3 or 4
researchers are present on the island at a time. While the Refuge's Station Manager has general oversight responsibility for all
activities that occur on the McKinney NWR properties, Dr. Spendelow is responsible for coordinating and directing the daily
research activities of the FITP staff.
Each year at the end of April (before the terns arrive), a PWRC work crew, NWR staff, and volunteers organized by TNC
visit Falkner Island to re-establish the gridded coordinate system and to enhance the nesting habitat for the Roseate Terns by
putting out nest boxes in rocky areas and half-buried tires in gravelly areas. The birds are then given 2-3 weeks to return and
occupy territories without being disturbed before the FITP staff begins residency in mid May, starts observing and identifying
the adults, and then begins censusing the nests of the Roseate Terns. (Click here for a picture of the nesting sites).
About 6000-8000 Common Terns and 260-360 Roseate Terns nest on Falkner Island each year. Roseate Tern nesting areas
are surveyed daily once the first eggs are laid, but Common Tern nesting areas are surveyed only 2-3 times a week after the
first chicks hatch. Roseate Tern eggs are numbered and weighed when first found. After they hatch, Roseate Tern chicks are
banded on one leg with a metal (incoloy or stainless steel) NBS band and, if possible, are then weighed daily until they fledge.
At about 5 days of age, Roseate Tern chicks also are given a long-lasting incoloy "field-readable" (F-R) band with a
4-character code stamped twice on it so that the bird can be identified relatively quickly if resighted as a fledgling or an adult at
a later date. About 3-5 days before fledging is expected, the large chicks are given colormarks on their wings and backs for
temporary identification at a distance once they become capable of sustained flight. Common Tern chicks are only given NBS
bands, and are not weighed or colormarked. (Click here for a picture of the colormarking process) .
In addition to banding all the chicks to monitor the comparative productivity of both species, we capture about 5% of the
nesting adult Common Terns and about 1/3 to 1/2 of the nesting adult Roseate Terns each year at Falkner Island to determine
the recruitment of new individuals into the breeding population. As part of the cooperative long-term study to examine adult
survival and intercolony movement rates, in 1988 we began colorbanding the adult Roseate Terns at the major colony sites so
that they could be identified at a distance more quickly without having to be recaptured. The observed loss rate of colorbands
from birds recaptured in 1989-1992, however, was much higher than expected, so in 1992 we began putting F-R bands on
adults at most other sites, and in 1994 we began putting a combination of FWS, F-R and 4 colorbands on adult Roseate Terns
at Falkner Island.
As part of the Roseate Tern metapopulation study, for several years we collected feathers from the terns at our study sites to
determine if these birds had high levels of heavy metal contamination. With the development of a new technique for sexing the
terns from the DNA present in their feathers, in 1994 we also began collecting feather samples as part of a study to examine the
unequal sex-ratio of the northeastern breeding population of this species. The existence of an unequal sex-ratio with more
females than males was suspected after the discovery of male- female-female trios and multiple-female groups, and the
development of this new technique for sexing both chicks and adults will allow us to study differential survival and dispersal of
the sexes from hatching onward.
In addition to doing the tern research, the FITP staff bands the other resident and migratory birds on Falkner Island, and
monitors the nesting Double-crested Cormorants and Great Black-backed Gulls on nearby Goose Island. The other nesting
species on Falkner Island since 1978 have included Canada Goose, Mallard, American Black Duck, American Oystercatcher,
Spotted Sandpiper, Herring Gull, Barn Swallow, European Starling, Red-winged Blackbird, and Song Sparrow, but the gulls
and starlings no longer nest on the island. The American Oystercatchers were unsuccessful in their first attempt in 1991, but
both they and the geese were successful in 1993, and the oystercatchers also helped keep predatory gulls away from the north
end of the tern colony that year.
As the nesting season comes to an end and the "data collection/fieldwork" part of the research is completed, the FITP staff
ends residency on the island each year by late August. The observation blinds are taken apart, the tires and nest boxes are
removed from the beach so they won't be swept away by winter storms, and the rest of the equipment is packed for winter
storage. All work does not end now, though, as from September through April data are summarized, analyses are done,
reports and manuscripts are written, presentations are given, plans for future fieldwork are discussed with the FITP
cooperators and the co-investigators working at the other study sites, and suddenly its spring and the terns are coming back to
the island to nest again.
The Falkner Island Tern Project is in part supported by:
The Nature Conservancy - Connecticut Chapter
55 High Street
Middletown, CT 06457-3788