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- TOWER HAZARDS
- As of the FAA's November 2, 1998 update, New York State had
728 tower sites of which 80 were tower farms containing more than one tower. NY ranks
30th among states in the number of towers per square mile. The large wilderness areas
of the Catskill and Adirondack Mountains have relatively few towers while the western,
central and downstate regions have higher concentrations.
New York State has complex geography including coastal areas on
Long Island and around Lake Ontario, and extensive mountainous areas across the state.
Mountain valleys and coastal regions can concentrate bird migration in specific weather
conditions creating above average tower hazard. Birds may fly lower over mountains
increasing the hazard of short towers located on hilltops and ridges. Little research
has been conducted regarding the impact of towers in mountainous regions. 23 new
towers were erected across New York State between the FAA's March 23, 1998 and November
2, 1998 updates.
- TOWERKILL STUDIES
- Two long-term towerkill studies have been conducted in New
York. In 1966, Arthur R. Clark, currently associate curator of vertebrate zoology
at the Buffalo Museum of Science, began a long-term study at three TV towers in southern
Erie County. WGRZ-TV, a 1,000-foot tower (2,310-feet above sea level) located on
Warner Hill Road in South Wales was built in 1954. In Colden, NY, the 750' WIVB -TV
tower (2,380-feet above sea level) was built in 1948; it was joined 14 years later
by the 1,076-foot WKBW -TV tower (2,808-feet above sea level). Clark checks the towers
in the fall only, as spring kills have proved to be relatively rare. To date, he
has found just over 20,000 individuals of 110 species. Clark based his master thesis
on early data from this study. He is currently compiling this monumental data set
for publication. His is the second-longest tower-kill study in North America. Before
1966, two of these towers were studied by Ken Able and Richard Roche.
In 1963, Wilifred Howard began a long-term study at an 850-foot
tower (2,549-feet above sea level) located on Hawley Hill about 3 miles WNW of Elmira,
NY. The tower originally broadcast WSYE-TV and now holds transmitters for WETM-TV
and WENY-TV. Wilifred Howard, with many volunteers, checked the tower for 20 fall
migration seasons. Tower surveys in spring revealed very few kills. Documented mortality
averaged more than 500 birds per fall over the 20 years of the study. The low fall
season total was 45 birds in 1967 and the high fall season total was 3,862 in 1977.
The highest one-night total was 1,817 on September 19-20, 1977. It appears when reading
the accounts that consistent efforts were made to check the tower first thing in
the morning during the fall monitoring period. Evidence of scavenging was noted and
about 30% of the area under the tower was inaccessible for surveying. So, actual
kills were likely to be considerably larger. Regular but small kills were tallied
in August and the most significant kills were noted in the latter half of September
and early October. For further details on this study see New
York Report #1.
In addition to the two long-term studies, several other notable
towerkill study efforts have been carried out. Fritz Scheider, Dorothy Crumb, and
members of the Onondaga Audubon Society checked the WIXT-TV 960-foot tower (2,550'
above sea level) near Pompey, NY on selected nights during the 1970s and 1980s. Results
from this study have periodically been published in THE KINGBIRD. One particularly
notable kill occurred sometime between September 4-9, 1981. After returning from
Labor Day weekend, the station engineer found a large kill and notified local birders.
912 dead birds of 39 species were collected under the tower. Many more were likely
eaten by scavengers. Clarence Klingensmith and Elizabeth Brooks checked a 219-foot
(2502-feet above sea level) microwave tower near the city of Alfred, NY during the
1980s. It is a free standing lighted tower structure without guy wires. While it
is a relatively short tower, this structure is built on a 2300-foot hilltop, one
of the highest in the region. Dozens of bird fatalities were documented.
In fall 1998, the New York State
Towerkill Survey was established.
This is a cooperative effort between bird lovers and communications companies across
the state to evaluate bird mortality at towers. The survey is conducted during fall
migration and the goal is to check as many towers as possible after nights when weather
conditions are conducive for a kill. Towers are initially scouted to see if the ground
cover under the tower allows for successful surveying. Then, permission to survey
is sought from tower owners. A hotline of volunteers, drawn largely from the plethora
of bird clubs across the state, is then activated on foggy or low cloud migration
nights. The survey hopes to study the relationship between weather and geography
on tower mortality, as well as compare mortality of different tower types and sizes.
At its fall 1998 meeting, the Federation of New York State Bird Clubs passed a resolution to address the problem of bird mortality at
communications towers in New York State.
BIRD MIGRATION STUDIES (pertinent to New York towerkill hazard)
- Bingman, V.P., K.P. Able & P. Kerlinger. 1982. Compensation, and the use
of landmarks by nocturnal bird migrants. Animal Behavior, 30:49-53.
BIRD STUDY ORGANIZATIONS (which might facilitate a tower study):
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