This was written by Darryl Mueller, a vehement opponent to wind plants:
CALIFORNIA ENERGY COMMISSION DRAFT OF 1991 STATED 61 GOLDEN EAGLES WERE
REPORTED KILLED IN 1989-1990 AT WIND RESOURCE AREA "ALTAMONT PASS", CALIF.
THIS REPRESENTS 4% OF THE ESTIMATED 500 GOLDEN EAGLES NESTING PAIRS IN
CALIF. (THELANDER, 1974).THIS HAS BEEN GOING ON YEAR AFTER YEAR SINCE EARLY
1980s. PEOPLE INVOLVED WITH THE STUDIES HAVE SHOWN A BIAS. THE PEREGRINE
FUND RECEIVED A $100,000 GRANT FROM U.S. WINDPOWER FOR STUDIES ON THE DECLINE
OF NEOTROPICAL MIGRATORY BIRDS IN CENTRAL AMERICA. PEREGRINE FUND T. CADE
AND B. BURNHAM HAVE MADE BIASED STATEMENTS THAT GOLDEN EAGLE POPULATIONS
ARE NEITHER THREATENED NOR VULNERABLE IN THE WESTERN STATES, EXCEPT LOCALLY
WHERE DEVELOPMENT DESTROYS NEST SITES (P700-001 C.E.C.). THIS IS CONTRARY
TO THE 1984-85 NEST SURVEY THAT SHOWED A LARGE DECLINE OF ACTIVE NEST TERRITORIES:
CENTRAL COAST RANGE 7 ACTIVE OUT OF 18 TERRITORIES, MOJAVE 3 ACTIVE OUT
OF 13 TERRITORIES, SOUTHERN SIERRA 5 ACTIVE OUT OF 14 TER.
------------------------------------------------------------------------
Avian Collision and Electrocution:
An Annotated Bibliography
California Energy Commission
October 1995
Publication Number: P700-95-001
8. Anderson, R.L., and J.A. Estep. 1988. Wind energy development in
California: impacts, mitigation, monitoring, and planning. California Energy
Commission, Sacramento. 12 pp.
Of 147 documented avian collision and electrocution incidents at California
wind energy facilities from 1985 to 1988, 101 have been raptors. Of these,
34 were eagles and 58 were hawks. In the Altamont Pass, an average of 11
eagle and 17 hawk incidents occurred annually. Ninety-one percent of all
documented avian mortality incidents resulted in mortality.
Note: These are just those of the "incidents" that have been reported,
not being part of a systematic survey. And since they are 7000 mills at
Altamont, chances are most bird deaths were "undocumented".
Mark Duchamp
22. Association of Bay Area Governments. 1987. Small but powerful: a
review guide to small alternative energy projects for California local
decisions. Oakland, California. 66 pp.
Bird collisions and electrocutions with wind turbines and associated
wires are cited as wind energy development impacts. "Although bird mortality
rates are relatively low, even these rates may be significant for endangered
raptors," notably the California condor, peregrine falcon, and bald eagle.
Power lines near water have been found to be more hazardous than in other
areas. Appropriate mitigation measures are discussed and techniques for
protecting birds are given. Special attention is given to the California
condor as a major source of conflict with wind farm development
59. BioSystems Analysis, Inc. 1990. Wind turbine effects on the activities,
habitat, and death rate of birds. Prepared for Alameda, Contra Costa, and
Solano Counties, California. 2 pp.
A two-year study to evaluate the extent and significance of the impact
of wind turbines on bird life was started in 1989 in Altamont Pass, California.
The study site included about 16 percent of the approximately 7,000 turbines
in the Pass. One hundred fourteen dead birds were found between February
1989 and February 1990. Eighty-one were raptors, the majority of which
were red-tailed hawks, American kestrels, and golden eagles. Sixty-three
percent of all deaths were attributed to turbine collision, 12 percent
to electrocution, 5 percent to wire collision, and 20 percent to unknown
causes. Most deaths resulted from amputation injuries. "It was estimated
that over 300 raptors were killed by windfarm-related injuries within the
Altamont Pass area during the first year of study (1989-1990)."
Note: 81 raptors killed by 16% of the turbines. Simple arithmetic would
yield a figure of 500 raptors for the whole park, not 300. One would need
to read the whole report to evaluate the reasons given. But more preoccupying
is the total disregard for the scavenging factor, which can make disappear
64% to 100% of the carcasses - see 102 below. Mark Duchamp
65. Bonneville Power Administration. 1987. Cape Blanco wind farm feasibility
study: final report. U.S. Department of Energy. Portland, Oregon. DOE/BP-11191-14.
187 pp.
Bird collision with wind turbines and transmission lines is discussed
in this assessment of wind energy development impacts. Collisions with
turbines are likely, with weather, flight altitude, and number and height
of operating turbines as contributing factors. Turbine collisions are most
likely to occur during the first two hours of night at the initiation of
migration (climbing altitude). Because of limited visibility and increased
collisions at night, the impact on nocturnal migrant populations is a primary
concern.
80. Byrne, S. 1983. Bird movements and collision mortality at a large
horizontal axis wind turbine. Cal-Neva Wildlife Transactions:76-83.
This study was conducted as a part of Pacific Gas and Electric Company's
performance monitoring program for a Boeing MOD-2 wind turbine located
at the edge of Suisun Marsh in Solano County, California. Bird mortality
was monitored for one year beginning in September 1982. As of January 1,
1983, five dead birds had been found at the turbine site.
Note: I found the full story in another document:
Boeing/PG&E MOD-2 Wind Turbine, California
Approximately five years later, bird movements and collision mortality
were studied as part of Pacific Gas and Electric Company's performance
monitoring program for a 350 ft Boeing MOD-2 wind turbine and associated
meteorological tower located on the western edge of the Suisun Marsh just
south of Cordelia, Solano County, California (Byrne 1983, 1985). Both raptor
and waterfowl movements were monitored prior to construction. Nocturnal
migration over the site was monitored during the fall of 1982 and the spring
of 1983 using a portable ceilometer and image intensifier system. Dead
bird searches were conducted five days a week during nocturnal migration
monitoring and once a week thereafter. Weather data were gathered to examine
relationships between migration intensity and weather conditions. Findings
indicated relatively low rates of waterfowl movements and nocturnal songbird
migration over the wind turbine site. Raptor activity in the area was moderate
to high. Migration rates were considerable lower than those recorded in
the eastern United States. During the year of mortality monitoring (1 Sep
1982ó31 Aug 1993), seven dead birds were found: one was observed to have
collided with the rotor (an American Kestrel), four more were thought to
have collided with the wind turbine, and two were thought to have collided
with guy lines or the meteorological tower. The mortality adjusted for
scavenger removal and detectability suggests an actual mortality during
the study as high as 54 birds.
Note: 1) These figures are for one single turbine. And the report specifies
that this is a "relatively low" bird activity and migration area.
2) If the 2750 turbines of the Valencian Community each killed 54 birds,
that would make 148.500 birds a year.
Mark Duchamp
102. Crawford, R.L. 1971. Predation on birds killed at TV tower. Oriole
36(4)
To test the effects of scavengers at the WCTV tower near Tallahassee,
Florida, 157 marked dead birds were placed out over a period of five nights.
The nightly loss of test birds to scavengers was between 64 percent and
100 percent. The author concludes that serious attention must be paid to
the predator/scavenger problem at towers if meaningful data are to be obtained.
Note: Up to 100%! This is paramount, as it invalidates practically
all studies made. The bird-kill figures can only be taken as an absolute
minimum figure unlikely to reflect reality.
And apart from the scavenger factor, we have the detectability factor
(effectiveness of researchers in locating all of the dead bird bodies in
the brush), and the cheat factor - one must consider the vested interest
of the windpower companies in having most carcasses removed by their on-location
employees before investigators see them - an easy task since the site is
normally investigated on a weekly basis, twice a week at best.
Finally, let us remember that: 1) All surveys are commissioned
by the windpower companies themselves, or by public bodies interested in
industry development, which makes them likely to be biased.
2) Most ecology groups, including raptor associations, receive public subventions,
making it difficult for them to raise their voice against government energy
plans, particularly when these promote a "green" energy. 3) Some
are even funded by the windpower industry: See the press article, and picture
of the cheque-presenting ceremony, involving a $100,000 cheque, the Peregrine
Fund, and US Windpower Inc. - available upon request: markduchamp@yahoo.es
109. Dawson, B. 1974. Letting them go: great horned owls go to school.
Museum Talk 48(2):45-48.
The Bird of Prey Survival Project at San Francisco Zoological Gardens
has a ward with two golden eagles, each with a wing missing due to power
line collision.
Note: Much of the following data relates to collisions with power
lines, telecommunication towers and their deadly guy wires, smokestacks
etc. It is pertinent data since: 1) Wind plants each have a
surrounding network of power lines and related infrastructure. 2)
If birds can collide with a non-moving obstacle such as a smokestack, it
is easy to understand how they can fly into the moving arms of a wind turbine.
120. *Drewien, R.1973. Ecology of Rocky Mountain greater sandhill cranes.
Dissertation. University of Idaho, Moscow. 82 pp.
Collisions with power lines accounted for 37 percent of the observed
sandhill crane mortality in the population that was studied in the western
U.S.
124. *Eaton, S.W. 1967. Recent tower kills in upstate New York. Kingbird
17(3):142-147.
Bird mortality from collisions with towers on the Allegheny Plateau
in New York is discussed, including a list of 57 species found dead during
1956. The author estimates that 10,000 songbirds are killed annually from
tower collision in the area.
135. Enderson, J.H. and M.N. Kirven. 1979. Peregrine falcon foraging
study in the geysers: Calistoga known geotheral resource area, Sonoma County,
California. Prepared for the U.S. Bureau of Land Management. Prepared by
Department of Biology, Colorado College, Colorado Springs, Colorado. 17
pp.
Power transmission lines are a hazard to peregrine falcons because
their attack dives may exceed 150 mph. "Collisions with wires are well-known:
at least six occurred in California in recent years ... and in 1978 in
Colorado a young Peregrine struck a power line 2 km from its eyrie and
suffered a broken wing."
136. Estep, J.A. 1989. Avian mortality at large wind energy facilities
in California: identifica- tion of a problem. California Energy Commission,
Sacramento. P700-89-001. 30 pp.
Avian mortality data resulting from collision or electrocution with
wind energy-related structures were solicited and compiled from a variety
of sources in 1988. The incidents occurred between November 1984 and April
1988 at Altamont Pass and Tehachapi Pass, California. One hundred eight
raptors of seven species were reported. Causes of mortality, injuries,
age class, season, and other results are discussed.
150. Garzon, J. 1977. Birds of prey in Spain: the present situation.
Pages 159-170 in: R.D. Chancellor, ed. Proceedings of World Conference
on Birds of Prey, International Council for Bird Preservation, Vienna,
Austria, 1-3 October 1975.
The greatest threat to birds of prey in Spain is from overhead cables.
165. *Goodwin, C.E. 1975. The winter season: Ontario region. American
Birds 29(1):48-57.
During fall 1974, kills at the Lennox power plant chimney and the Barrie
and London TV towers in Ontario, Canada, totalled 7,550 birds. Red-eyed
vireos (1129), ovenbirds (1038), and magnolia warblers (920) were the species
most commonly killed
197. *Herren, H. 1969. The status of the peregrine falcon in Switzerland.
Pages 231-238 in: J. Hickey. Peregrine falcon populations: their biology
and decline. University of Wisconsin Press, Madison, Wisconsin.
Of 14 dead peregrine falcons examined between 1952 and 1965, five had
collided with wires. Overhead wires are the main cause of eagle owl fatalities
and have contributed to the extermination of the species in much of its
former range in Switzerland.
203 *Hoskin, J. 1975. Casualties at the CKVR-TV tower, Barrie. Nature
Canada 4(2):39-40.
During August and September 1974, 4,900 dead birds were collected at
the newly constructed, 1,000-foot tower in Ontario, Canada. Large kills
occurred in September on the 10th (409 birds), 13th (704), 14th (371),
and 21st (1,523). Among the casualties were 1,000 bay-breasted warblers
and 900 ovenbirds. Other species with high losses were the northern parula,
northern waterthrush, Cape May warbler, and rose-breasted grosbeak.
206. Howell, J.A. and J.E. DiDonato. 1991. Assessment of avian use and
mortality related to wind turbine operations: Altamont Pass, Alameda and
Contra Costa Counties. Submitted to U.S. Windpower, Inc., Livermore, California.
72 pp.
From September 1988 to September 1989, 359 wind turbines were sampled
for bird mortality, yielding 42 bird recoveries. Site differences were
significant: multiple strikes tended to occur at swales (depressions) and
hill shoulders where ridge lines had a stairstep effect. Some species,
particularly golden eagles, were more susceptible to impacts from wind
turbines. The authors express concern that the number of golden eagle mortalities
at U.S. Windpower's facility may have a significant impact on local populations.
In addition, the authors recommend that hypotheses about the relationship
of visibility, topography, and mortality should be tested to evaluate methods
to reduce avian mortality in the Altamont Pass, California.
222. Jurek, R.M. 1994. Condor information leaflet. California Department
of Fish and Game, Sacramento. 4 pp.
Of eight California condors released into the wild in 1992, three were
killed from collision or electrocution at power lines.
228. *Kemper, C.A. 1958. Destruction at the TV tower. Passenger Pigeon
20(1):3-9.
In fall 1957, three large kills, including one estimated at 20,000
birds (based on 1,525 of 40 species collected), were reported from the
1,000-foot Eau Claire, Wisconsin, TV tower. Warblers dominated the kill
lists.
241. Kretzschmar, H. 1969. Grosstrappen fliegen gegen Hochspannungsleitung.
Falke 16:94-95. (In German.)
Several instances of great bustards striking power lines in 1967 and
1968 are reported
271. *Lupient, M. 1961. Fall migration: western Great Lakes region. Audubon Field Notes 15(1):42-44.
An estimated 12,000 birds died at towers in the Western Great Lakes region on the night of 21 September 1960. Of these, 1,225 (42 species) were collected at Chippewa Falls, Wisconsin. Other kills in western Wisconsin occurred earlier in the month.
272. *Lupient, M. 1962. Fall migration: western Great Lakes region.
Audubon Field Notes 16(1):34-35.
From 2 September to 10 October 1961, 5,097 birds were collected at
the Eau Claire, Wisconsin, TV tower. These were estimated to be 10-20 percent
of the actual total kill.
273. Maehr, D.S., A.G. Spratt, and D.K. Voigts. 1983. Bird casualties
at a central Florida power plant. Florida Field Naturalist 11:45-68.
On 23 September 1982, 1,265 birds (30 species from an estimated kill
of 3,000) were collected below chimneys at the Crystal River Generating
Facility, Citrus County, Florida. The most abundant numbers were white-eyed
vireos (49 percent), northern parula (12 percent), red-eyed vireos (9 percent),
common yellowthroat (7 percent), and palm warbler (5 percent). On 24 September,
an estimated 2,000 birds were involved in chimney collisions. "A fan-shaped
distribution of dead birds reflected the prevailing northerly winds." The
authors stress the need to investigate lighting alternatives; lighting
appears to attract birds under overcast conditions. Only 5 percent of deaths
occurred at shorter chimneys (152 m) painted with alternating red and white
bands and with flashing red lights. The taller chimneys were unpainted
and had flashing white "strobe" lights.
280. McCrary, M.D., R.L. McKernan, R.E. Landry, W.D. Wagner, and R.W.
Schreiber. 1983. Nocturnal avian migration assessment of the San Gorgonio
wind resource study area, spring 1982. Prepared for Southern California
Edison Company, Research and Development, Rosemead, California. Prepared
through the Los Angeles County Natural History Museum Foundation, Section
of Ornithology, Los Angeles. 121 pp.
Research was conducted on spring 1982 bird migration in the San Gorgonio
Wind Resource Study Area (WRSA) to examine characteristics of nocturnal
migration in the area and to assess the potential collision impact on birds.
It was determined that the WRSA is heavily utilized by birds as a migratory
flyway. "From these studies avian collisions with wind turbines in the
WRSA will almost undoubtedly occur." Approximately 182,000 birds per km
could potentially come into contact with wind turbine generators each spring
in the WRSA. "Although only a small fraction of these birds is likely to
collide with wind turbines in the WRSA, even a collision rate of 0.5 percent
would yield several thousand deaths per spring season." Recommendations
for further study and mitigation measures are included.
287. Medsker, L. 1982. Side effects of renewable energy sources. National
Audubon Society, Environmental Policy Research Department Report No. 15.
73 pp.
"Barriers to wildlife movement" are cited as direct impacts of Wind
Energy Conversion Systems (WECS), with the consequence of "possible destruction
of birds and insects colliding with wind machines." Choosing sites to avoid
migration and flight patterns is recommended.
296. Monk, G. 1982. California peregrine falcon reproductive outcome
and management effort in 1982. Draft. U.S. Fish and Wildlife Service, Endangered
Species Office, Sacramento, California.
Out of 124 nestling peregrine falcons banded, three bands were returned
in 1982. Two of those were from birds that had struck power lines.
324. Olendorff, R.R. and R.N. Lehman. 1986. Raptor collisions with utility
lines: an analysis using subjective field observations, final report. Prepared
by U.S. Bureau of Land Management. Prepared for Pacific Gas and Electric
Company, San Ramon, California. 73 pp.
Data were collected internationally on 88 probable raptor collisions
with utility lines, including species, age class, type of line, configuration,
and injuries. Peregrine falcons, bald eagles, golden eagles, red-tailed
hawks, and ospreys were the species most commonly reported.
325. Olendorff, R.R., R.N. Lehman, and P.J. Detrich. 1986. Biological
assessment: anticipated impacts of the geotheral public power line on federally
listed threatened or endangered species, with emphasis on the bald eagle.
U.S. Bureau of Land Management, Sacramento, California. 72 pp.
Based on a two-year study, this biological assessment examines the
proposed Geothermal Public Power Line's (GPPL) impact on endangered species
and their habitats, especially the bald eagle. The project includes a 55.7-mile
transmission line from the Geysers to Williams, California. The Bureau
of Land Management concludes that the project "may affect" an endangered
species "because of the possibility of one or more bald eagles in the area
colliding with the GPPL..." Impacts to the Pacific northwest eagle population
could occur on two levels: "(1) general impacts to raptor populations resulting
from power line collisions; and (2) the specific risks to [individual]
bald eagles within each proposed GPPL corridor." Mitigation measures are
discussed.
327. Olsen, J. and P. Olsen. 1980. Alleviating the impact of human disturbance
on thebreeding peregrine falcon II: public and recreational lands. Corella
4(3):54-57.
Of 14 peregrine falcons found dead in Switzerland, five had been killed
from striking wires. One hunting peregrine falcon was witnessed colliding
with a telephone line. Impacts on other species are discussed: overhead
wires are believed to be one of the main causes of injuries to merlins
in Britain, and five injured Australian hobbies (Falco longipennis) appeared
to have collided with wires. More research is warranted in Australia regarding
avian electrocutions and collisions with overhead wires. The authors recommend
that wires and fences be placed far from eyrie and hunting sites. Young
falcons are particularly susceptible to wire collision.
331. Orloff, S. and E. Cheslak. 1987. Avian monitoring study at the
proposed Howden windfarm site, Solano County, Phase I: draft report. BioSystems
Analysis, Inc., Sausalito, California. J-249. 34 pp.
A proposed wind park would be located in the Benicia Hills, Solano
County, California, in close proximity to the Suisun Marsh. Suisun Marsh
is an important wetland wintering area for waterfowl along the Pacific
Flyway, as well as an important raptor winter-foraging area. Ten avian
species with special legal or management status, including bald eagle,
peregrine falcon, and golden eagle, occur or may occur at the site. Observation
data on bird species, age, sex, flight behavior, and other environmental
variables were collected between 27 November 1985 and 14 November 1986.
It was concluded "that there is a potential for bird collisions with the
proposed wind turbines."
332. Orloff, S. and A. Flannery. 1992. Wind turbine effects on avian
activity, habitat use, and mortality in Altamont Pass and Solano County
wind resource areas. Prepared by BioSystems Analysis, Inc. Tiburon, California.
Prepared for the California Energy Commission, Sacramento. Grant 990-89-003.
150 pp. plus appendices.
Six seasons of field work (1989-1991) in the Altamont Pass, California,
were conducted with the purposes of evaluating the extent and significance
of the impact of wind turbines on birds, identifying the causes and factors
contributing to bird deaths, and recommending mitigation measures. Of 182
dead birds found on the ground near turbine and transmission line structures,
119 (65 percent) were raptors. Fifty-five percent of all raptor deaths
were attributed to turbine collisions, 8 percent to electrocution, 11 percent
to wire collision, and 26 percent to unknown causes. Recommendations include
further studies to investigate factors contributing to mortality and to
determine effective modifications to reduce deaths.
333. *Owen, M. and C.J. Cadbury. 1975. The ecology and mortality of
swans at the Ouse Washes, England. Wildfowl 26:31-42.
Of 128 swan mortalities where the cause of death was known, 49 (38
percent) were due to collisions with power lines. Three species of swan
were studied: Bewick's, Mute, and Whooper.
335. Pacific Gas and Electric Company. 1985. MOD-2 wind turbine field
experience in Solano County, California: final report. Prepared by PG&E's
Department of Engineering Research, San Ramon, California. Prepared for
Electric Power Research Institute, Palo Alto, California. EPRI AP-4239.
Project 1996-3. 100 pp. plus appendices.
This two-year field study of a 2.5-megawatt MOD-2 wind turbine in Solano
County, California, was conducted to evaluate performance and environmental
impacts, including the effects on bird populations. Avian collision mortality
was monitored for one year (September 1982 through August 1983). Seven
dead birds were found, five under the wind tower (three passerines, a waterbird,
and a raptor) and two beneath the meteorological tower (passerines). Collisions
occurred during all lighting and weather conditions. Low rates of waterfowl
movement and nocturnal passerine migration were noted over the site, and
raptor use of the area was moderate. The report concludes that the impact
of the wind tower on birds is "minimal."
346. Phillips, P.D. 1979. NEPA and alternative energy: wind as a case
study. Solar Law Reporter 1(1):29-54.
This article examines the issue of whether and when the National Environmental
Policy Act (NEPA) applies to alternative energy sources, using wind as
a case study. Potential environmental impacts of wind development are discussed,
and construction of a 1.5-megawatt wind turbine is used for illustrative
purposes. The hazard of bird collision is noted, especially with regard
to migratory birds; "[t]he risk would be small for high flying migratory
waterfowl, but would increase for low flying nocturnal migrants, such as
many songbirds."
349. Pogson, T.H. and S.M. Lindstedt. 1988. Abundance, distribution
and habitat of Central Valley population greater sandhill cranes during
winter. Biology and Wildlife, University of Alaska, Fairbanks.
Power line collisions seem to be the largest source of unnatural mortality
for California's Central Valley sandhill crane population. The authors
feel reported results could be slightly skewed towards collisions with
power lines due to the bias in finding carcasses.
351. Portland General Electric Company. 1986. Cape Blanco wind farm
feasibility study. Technical Report No. 11: Terrestrial ecology. Bonneville
Power Administration, Portland, Oregon. DOE/BP-11191-11. 56 pp.
This report evaluates the potential terrestrial ecology impacts of
the construction and operation of a wind energy conversion system located
near Cape Blanco in Curry County, Oregon. "All three Cape Blanco wind farm
alternatives under consideration pose a potential threat of collisions
for birds flying at low altitudes." Nocturnal songbirds are especially
expected to be impacted. Guy wires and lighting of the units are identified
as probable collision hazards. Potential impacts of support facilities
(two transmission line routes to an existing Bonneville Power Administration
230-kV line) are evaluated
356. *Purrington, R.D. 1969. Fall migration: central southern region.
Audubon Field Notes 23(1):65-70.
At the WSM tower in Nashville, Tennessee, 5,408 birds (4,857 warblers)
died the night of 25 September 1968. This figure is more than half of the
total mortality from Nashville towers and ceilometers in the past 20 years.
361. Riegel, M. and W. Winkel. 1971. On death causes of white storks
(C. ciconia) according to ringing recovery reports. Vogelwarte 26(1):128-135.
(In German; English summary.)
In Germany, of 294 storks for which the cause of death was known, 226
(77 percent) died from collisions with telegraph wires. Inexperienced birds
were more prone to collide with wires than were older birds.
375. San Francisco Chronicle. 1984. Many eagles electrocuted, study
by utility finds. San Francisco Chronicle, Friday, April 27.
The basis of this article seems to be the Electric Power Research Institute
(EPRI) report on preventing golden eagle electrocutions. In the three-year
study of eagle habitats in six western states -- Oregon, Idaho, Wyoming,
Utah, Nevada, and New Mexico -- the carcasses of 343 electrocuted eagles
were examined. The article cites a U.S. Fish and Wildlife Service study
where electrocutions were responsible for 23 percent of 597 golden eagle
deaths analyzed between 1963 and 1982; shootings accounted for 18 percent
of those deaths.
383. Scott, P. and The Wildfowl Trust. 1972. The swans. Houghton Mifflin
Company, Boston. 242 pp.
Overhead wire collision has undoubtedly been a major factor in limiting
populations of swans in some areas. Some birds are killed by impact with
power lines and other by electrocution. "Those which survive the collision
are often stunned and fall heavily to the ground. In the absence of serious
injury, they eventually recover and fly off, but for awhile they are vulnerable
to foxes and other predators." Sixty-five percent of swans recovered died
from collision; fifteen percent of those deaths were due to overhead wires.
Swans have slow flight, low maneuverability, and poor forward vision, making
them especially susceptible to collision with wires.
Note: bustards are even heavier than swans, and Spain is their last
stronghold in W.Europe. The windfarm boom in that country will add
to the casualties from regular power lines.
Mark Duchamp
384. Scott, R.E., L.J. Roberts, and C.J. Cadbury. 1972. Bird deaths
from power lines at Dungeness. British Birds 65(7):273-286.
Bird mortality was monitored from January 1964 to November 1970 along
a section of power line in an area heavily used by migrants. Of the 1,285
dead birds (74 species) collected, starlings (489) and gulls (138) suffered
the heaviest losses, followed by various nocturnal migrants (rails, turtle
doves, thrushes, warblers). Few diurnal migrants were found. Because many
carcasses were lost to scavengers, the kill may actually have exceeded
6,000. Attempts to make the wires more visible with luminous orange tape
were inconclusive. A list of the casualties and the results of experiments
to test scavenger removal of dead birds are given. The siting of power
lines is a critical factor in the amount of mortality at a given location,
and other factors such as height of migration flights and flock configuration
are important in determining which species are killed.
395. Smith, W.E. and M.W. Nelson. 1976. Constructing electric distribution
lines for raptor protection. Proceedings of the American Power Conference
38:1294-1303.
National Audubon Society members and associates working in the field
reported over 300 eagle electrocution incidents throughout the United States
in 1975. Ninety-eight percent of the birds killed were young, just learning
how to fly. The authors outline several construction strategies that can
help eliminate the risk of avian electrocution. Beneficial aspects of power
lines for raptors are also discussed
433. Ultrasystems, Inc. 1985. Potential effects of the proposed Fayette
Manufacturing Corporation Bald Mountain wind energy project on the California
condor: preliminary draft report. Submitted by Ultrasystems Inc., Environmental
Systems Division, Irvine, California. Submitted to Fayette Manufacturing
Corporation, Tracy, California. 37 pp.
Wind turbine collision is a principal issue concerning the California
condor. "The loss of a single individual is considered significant by persons
associated with the recovery effort" because of the bird's critical status.
A table of persons contacted regarding wind farm development effects on
raptors and other biota is given
Note: I am glad to see that some ornithologists do think the way I do about
wind turbines and endangered bird species.
Mark Duchamp
444. *Weir, R.D. 1974. Bird kills at the Lennox generating plant, spring and autumn 1974. Blue Bill 21(4):61-62.
Floodlights illuminating the 650-foot chimneys of the Ontario, Canada,
power plant were dimmed from 15 April to 8 June and from 9 August to 2
October 1974, but birds were still killed, with 92 casualties in the spring
and 1,188 in the fall (35 species overall). Since the first chimney was
built in fall 1972, 5,288 birds were killed. In 1974, 98 percent of the
casualties were warblers and vireos, with magnolia warblers (33 percent)
and red-eyed vireos (11 percent) the most common casualties. Large kills
occurred on the clear nights of 13-14 September (501 killed) and 14-15
September (508 killed). On both nights, winds were strong and flight call
counts indicated that birds were flying lower than usual. Migrants were
easily seen in the glow of city lights. In anotherincident on the weekend
of 15 September, 1,524 birds were killed at a new 1,200-foot tower in Barrie,
Ontario. Lists of casualties by date of collection and a summary of flight
call counts and weather conditions are given.
445. *Weir, R.D. 1976. Annotated bibliography of bird kills at man-made
obstacles: a review of the state of the art and solutions. Canadian Wildlife
Services, Ontario Region, Ottawa. 85 pp.
A 28-page introduction to this bibliography summarizes what is known
about bird migration and the effects of weather on migration and mortality.
It also includes a literature review on bird losses at lighthouses, ceilometers,
floodlit obstacles, towers, tall buildings, and telephone and power lines.
A list of TV towers of various heights throughout the United States is
included. "Nocturnal bird kills are virtually certain wherever an obstacle
extends into the air space where birds are flying in migration. The time
of year, siting, height, lighting and cross-sectional area of the obstacle
and weather conditions will determine the magnitude of the kill." Four
hundred seventy-one references, most with brief descriptions, are included.
446. *Weir, R.D. 1977. Bird kills at the Lennox generating station, spring and autumn 1977. Blue Bill 24(4):40-42.
For the sixth straight year, kills were reported at the chimneys of
the Ontario Hydro plant at Bath, Ontario, Canada. The total of 2,699 (61
species) casualties, of which 2,575 were fall migrants, was the largest
since the first chimney was constructed in 1972. Due to a change in floodlighting
procedures, the lights were inadvertently left on during nights of heavy
migration and several large kills resulted. On 23 August, 908 birds were
killed under overcast skies before the lights were extinguished at 0117.
Similarly, 1,172 birds died on the night of 19 September, during a driving
rain. The lights were not turned off until 0500. The sky was clear on the
night of 12 September and the floodlights were not used, partly in response
to the public reaction to the kills that were reported in the Toronto Globe
and Mail. The system of turning off floodlights during the spring and fall
migration periods was in force prior to 1977 and will be resumed beginning
spring 1978. A complete list of casualties is provided, and the 11,230
casualties recorded since fall 1972 are totalled by season
460. Wilmore, S.B. 1974. Swans of the world. Taplinger Publishing, New
York.
The cause of death was diagnosed for 1,051 of 2,156 mute swans recovered
in Britain between 1960 and 1965, and "the greatest danger to their mortality
was reported to be collision with overhead wires." During two months in
1963, a quarter-mile stretch of power line in Kent killed 21 swans, 30
percent of the total flock. Swans' weak frontal vision was noted as a contributing
factor.
Note: The bustard in Spain has the same problem. Mark Duchamp
462. Winkelman, J.E. 1992a. The impact of the Sep wind park near Oosterbierum
(Fr.), the Netherlands, on birds, 1: collision victims. DLO-Instituut voor
Bos- en Natuuronderzoek. RIN-rapport 92/2. 4 volumes. (In Dutch; English
summary.)
An experimental wind park consisting of 18 wind turbines (300-kW, three-bladed,
35 m tower height, 30 m rotor diameter), seven meteorological towers, and
three control buildings, was studied between 1984 and 1991. A series of
reports was published on avian mortality in the park (entries #462-465).
In this study on collisions, avian collision rates increased with an increase
in the number of operating turbines. Carcasses were found distributed over
most of the park with a slightly lower concentration of carcasses in the
middle section, suggesting that cluster formations of turbines may reduce
collision risk compared to straight line or single row formation. Most
collision victims were found in autumn and spring and after nights with
poor flight and visibility conditions.
463. Winkelman, J.E. 1992b. The impact of the Sep wind park near Oosterbierum
(Fr.), the Netherlands, on birds, 2: nocturnal collision risks. DLO-Instituut
voor Bos- en Natuuronderzoek. RIN-rapport 92/3. 4 volumes. (In Dutch; English
summary.)
In this portion of the study (see also entries #462-465), researchers
observed a collision rate of 68 birds per week at night. The difference
in the number of mortalities observed at the moving turbines compared to
those calculated indicated that a proportion of birds may have disappeared
through predation or were missed due to insufficient searching. Mortality
rates may have been even higher due to uncounted birds that may have collided
with a turbine, flown away and died later. Illumination of the turbines
was not recommended: in conditions of "poor visibility...the illumination
may even attract birds, which may increase the risk of collision."
465. Winkelman, J.E. 1992d. The impact of the Sep wind park near Oosterbierum
(Fr.), the Netherlands, on birds, 4: disturbance. DLO-Instituut voor Bos-
en Natuuronderzoek. RIN-rapport 92/5. 4 volumes. (In Dutch; English summary.)
In this portion of the 1984-1991 experimental wind park study (see
also entries #462-464), disturbance effects of the wind park on avian breeding,
feeding, resting, and migration are discussed.