ML19344D891
| ML19344D891 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse  |
| Issue date: | 11/15/1979 |
| From: | Jackson W, Temme M BOWLING GREEN STATE UNIV., BOWLING GREEN, OH |
| To: | |
| Shared Package | |
| ML19344D889 | List: |
| References | |
| TAC-42152, NUDOCS 8008260271 | |
| Download: ML19344D891 (22) | |
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COOLING TOWERS AS OBSTACLES IN BIRD MIGRATIONS I
i MANFRED TEMME AND WILLIAM B. JACKSON I ENVIRONMENTAL STUDIES CENTER BOWLING GREEN STATE UNIVERSITY BOWLING GREEN, OHIO 43403 I
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I C00LIflG TOWERS AS OBSTACLES IN BIRD MIGRATIONS O
Suma ry Observations of b'ird strike incidents at the Davis-Besse site, initiated in 1972, have been continued each spring and fall migra-tion period. During these observations daily mortalities always have been less than 100. The maximum recorded (September 25,1976) was 84, although some were floating in basin and may have come from the previous day. The highest number certainly recorded for a single day was 59 (May 17,1974). The most birds recovered in a year was 515 (1974). In 1979 the total was 60. Almost 80'.' of the strikes occurred at the cooling tower.
Songbird species that are nocturnal migrants made up almost all of the bird strikes. Only occasionally were herons, grebes, coots, gallinules, gulls, and terns involved; and the many raptors, ducks, geese, and swans that abound in or migrate through the area j have never been found. Although systematic observations during non-migratory periods have not been carried out, through scattered obs-ervations and circumstantial evidence, we believe that few summer i and winter resident birds become strike victims.
I Mortalities were more frequent with adverse weather, warm i fronts and precipitation in the spring and passage of cold fronts
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Lighting that reduced direct glare on the cooling tower and l
other structures but provided diffuse site illumination appeared l
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l correlated with reduced bird strikes. The present sodium vapor lights seem to provide the best overall effect yet observed.
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Af ter seven years of observations, the cooling tower and other site structures are considered to have had no significant adverse effect on bird populations, either local or migratory.
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I Introduction
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Tall, man-made structures, such as radio and television towers, monuments, smoke stacks, light houses and other buildings, are known to be lethal obstructions to migrating birds. Not only the tower itself, but the associated guy and electrical wires may cause injury or death to birds, especially the nocturnal migrants. A vast number of mortality reports have already emerged across the country, indi-cating the seriousness and extent of this problem.
Tall TV towers seem to be the most hazardous to avian migrants, causing losses up to 2000 birds in several nights during fall migra-tion in Florida (Stevensen 1956,1958). During an entire fall sea-son 4900 birds were collected at a TV tcwer in Ontario (Hoskin 1975).
Numbers occasionally reach as high as 30,000 birds, as reported from the TV tower at Eau Claire, Wisconsin for two nights in September 1963 (Kemper 1964). An extensive annotated bibliography on this sub-I ject has been compiled by Avery et al. (1978).
Information on mortalities at nuclear power plant structures are rel'atively scanty; monitoring programs have been initiated at only a few sites. Such observations have been undertaken at the Davis-Besse Nuclear Power Plant, where the number of bird kills I was lower than reported for many TV towers. Obsersations also were begun at the four 370-foot cooling towers at Three Mile Island -
Nuclear Station on the Susquehanna River. During their preoperational I
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reporting period (1973 - 1974) mortalities were very low (37 speci- ,
mens). Also during the 1974 - 1975 operational period, only 29 mor-talities were reported (Pentecost and Muraka 1976; Mudge and Firth 1975). fio detailed reports are known to be available from the Tro-Jan fluclear Power Plant situated near Portland, Oregon in the Col-umbia River Valley, which has a natural draft tower identical to that at the Davis-Besse Plant. Mortalities were reported by Dr.
Stanley C. Katkansky, their ecologist, to be of little significance.
Only occasional incidents at the tall stacks at Detroit Edison's I Monroe, Michigan plant and the cooling tower at the nearby Fermi site have been reported (Jackson et al. 1977).
At the Davis-Besse fluclear Power Plant on the SE shore of Lake Erie near Port Clinton, the shell of a large, natural-draft cooling tower (495 ft high, and 410 ft wide at the base) was constructed I during 1972 and the spring of 1973. Regular observations and moni-toring studies were carried out each subsequent spring and fall migration season. Results during the initial observation periods (fall 1972, spring and fall 1973) were summarized by Rybak et al.(1973).
The goals of this study were:
I 1. To study the bird-strike incidents during the pre-cperational and operational periods.
- 2. To identify numbers of species and individuals affected at the different structures and buildings.
- 3. To determine through necropsy the extent of injury.
- 4. To evaluate the relationships between mortalities and weather patterns.
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- 5. To determine the effects of site lighting on ,
the number of mortalities.
Methods At the Davis-Besse site, bird mortality has been monitored for the seventh consecutive spring and eighth fall migration seasons.
The surveys consisted of almost daily, early-morning site visits in spring between mid-April and mid-June and in fall between the first of September and late October. The procedure included examination of the roof areas and the grounds around the reactor-turbine build-ing complex and the base of the cooling tower.
Areas under major guy wires, transmission lines, a meteorologi-cal tower, a microwave tower, as well as around the cooling tower were inspected. All surveys included the recording of current envir-onmental conditions, numbers and species of birds, and their locations.
All birds collected were frozen for later necropsy.
Beginning in fall 1976, test runs involving the cooling tower operation occurred. The subsequent slashing water in the tower base prevented determination of the locations of sorre mortalities, and an unknown number of birds drifted away through the water outlets.
lI l Many birds, however, were secoped up with a long-handle dip-net.
Of ten some could f.e retrieved only after they had been drifting for several days ant' were badly decomposed, making detailed examin-ations difficu'it. However, with the help of a reference collection, it was possible to ideatify most of these carcasses.
Results and Discussions During the mortality monitoring periods between fall 1972 and fall 1979, a total of 15-11 bird carcasses were collected at the I
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I Davis-Besse site. Of that total 1229 birds (78.7%) had collided with the cooling tower, 222 (14.2%) with the Unit I structures
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l (turbine and reactor building), and 110 (7.0%) at the guy wires or the weather tower on the site (Table 1). flotable is that the majority of birds that collided with the tower were small songbirds (Passeri-formes) (Table 2). Most were nocturnal migrating species, especially warblers (family Parulidae), vireos (Vironidae), and kinglets (Sylviidae).
Larger birds, such as the many waterfowl species that abound the adjacent marshes and pnnds, virtually were not involved.
During the spring migrations,483 carcasses (30.9%) were found, consisting mostly of warblers (55.7%), fringillids (10.4%), and "others", which included rails, thrushes, blackbirds, vireos, brown creepers, woodpeckers, and pigeons. Golden-crowned kinglets and ruby-crowned kinglets rarely were found in spring at the Davis-Besse structures (Fig. 1). Similar observations also were made at the Leon County, Florida TV-tower (Stoddard 1962 and Crawford 1973).
Differential spring and fall migration patterns of these kinglets may be responsib!c for this phenomenon.
The most comon warblers killed during the spring period 1972 through 1979 were the magnolia warbler (Dendroica magnolia) and yellowthroat (Geothlypis' trichas), followed by ?!ashville warbler (Vermivora ruficapilla) (Table 3). Other warbler e 3ecies were found -
l in still smaller numbers over the years. In contrast, the Leon County, Florida TV-tower spring kills of the first two species were either small or almost nonexistent in contrast to greater kills in fall. At that tower, only one specimen of the Nashville warbler was found in October (Stoddard and florris 1967).
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The overall results of spring mortalities at the Davis-Besse -
plant reflect typical migration patterns and are, in contrast to fall patterns, spread more narrowly over only a few weeks. This is especially apparent with the magnolia warbler and the bay-I breasted warbler (Dendroica castanea) (Fig. 2). Kills of red-eyed vireos (Vireo olivaceus) in spring were found to be almost as high as in fall (Fig. 2). A similar ratio was found at the Lecn County, Florida TV-tower (Stoddard and Norris 1967).
In fall seasons after nesting, kills (1071 specimens [68.9%])
were more frequent because of larger numbers of birds migrating.
Again warblers were the most affected (56.5%). Both species of kinglets (23.0%) were well represented (in contrast to the spring seasons), while numbers of mimids and finches were lower (Tables 1, 2, and 3). Late in the season both species of kinglets, magnolia warbler, yellowthroat, and the red-eyed vireo were found in rela-tively large numbers (Figs.1, 2, and 3).
In the spring most birds (54%) were recovered in the NE sector of the cooling tower. This suggests that the birds striking the southern exposure of the tower may have drif ted, while falling, with the southwesterly wind and/or other currents around the tower to the NE sector (Fig. 4A). The picture was reversed during the fall sea-son, when most carcasses (52%) were found in the SE sector (Fig. 48).
Birds striking the tower from the north or northeast may have drif ted with prevailaing northwesterly winds around the tower to the more southeastern locations.
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In general, mortality patterns and composition of species .
agreed with the results found by many other observers, who report-ed that warblers most frequently were killed at towers. Others also reported numerous kills of kinglets and often thrushes.
I Necropsy Examination Necropsy examination included determinations of the extent of hematoma under the skull, presence or absence of bone fracturcs (humerus, ulna, radius, tibiotarsus, and tarsometatarsus), bill damage, and " broken" neck and skulls. Each bird collected was aged by determining the degree of skull ossification. These data are summarized for the period from 1972 - 1979. Most frequent injuries were to the head and bill, indicating the occurrence of frontal impact (Table 4). Red-eyed vireos, however, suffered significantly less bill injuries than warblers and kinglets (paired t-test, P <0.001).
Weather Patterns and Mortalities Spring:
Past observations and analyses by W. A. Peterman have shown that bird mortalities tend to be related to low pressure systems, with migration occurring on the trailing edge of highs in advance of an oncoming cold front, with southerly wind flow. This synoptic weath-er pattern is of ten accompanied with warm front-type of precipitation, haze, low cloud ceiling, ana poor visibility.
Fall:
In fall, migration mortalities tend to be associated with the occurrence of high pressure. Increased migration of insectivorous birds usually follows a cold front passage, associated with northerly flow of air. Also in the fall, mortality occurs in association with adverse weather conditions.
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J Illumination Patterns at the Structures No accurate or precise data apparently exist that define light-ing patterns during the early cor.struction period at the Davis-Besse structures. During favorable weather, construction continued at night, and worki'ng areas were illuminated with incandescent and mercury vapor lights. It was during this phase that considerable numbers of bird strikes occurred.
In 1976 formal revisions of the site lighting system were re-corded, but these occurred only around the Unit I buildings. Appar-ently no changes were made at the cooling tower, which generally utilized red navigation lights at night and white strobe lights during the day.
In 1977 mercury lights were installed around the Unit I build-ings, but no changes were made in the cooling tower area. In the spring of 1978 light intensity readings were taken at ground level.
The average of 105 readings was 1.7 foot candles.
By the spring of 1979 a conversion to high-pressure scdium-vapor lights had been completed for all areas, including the road and switchyard areas adjacent to the cooling tower. Light intensity readings, supposedly comparable to those taken in 1977, resulted
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in an avercge of 4.6 foot candles. This is nearly three times the
, light intensity recorded under the mercury lights.
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several elevations of the tower are not available for any period of l its history. Consequently, only speculation is possible relative to lignting patterns and bird strikes. At the current time light readings along the adjacent road are 1.0 foot candles or less.
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Along the tower base adjacent to the road, light readings were 0.15 ,
to 0.25 foot candles. On the opposite towee side, no readings were obtainable. (Floodlamps mounted adjacent to the tower base are not ncrmally used ).
Although the majority of these sodium-vapor, orange-colored lights were installed around the Unit I structures and the adjacent switchyard, diffuse lignt indirectly illuminates the tower, espe-cially the S, SE, ard E sections. flight observations during a time with low cloud ceiling and light drizzle revealed that it is possible I to see the tcwer easily and even recognize the concrete seams from top to the bottom. Under such conditions birds should have been able to see the tcwer early enough to avoid a collisien, even if the tcwer had tacen approached from the f1E. The north and west ' aces of the tower are darker, but are still recognizable 3s a silhouette be-I cause of sufficient ambient lighting.
Various lighting designs or warning devices have been considered to ameliorote the biru stikes at towers. Preliminary Canadian work indicated that red flashing lights worked cest to catch the atten-tion of birds, but it has not yet been determined whether these find-ings can be adapted to induce aversion (Belton 1976, Solman 1976).
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At the Davis-Besse plant, when using the white strobe lights on top of the cooling tower during two migration periods (spring, fall 1975),
no deviation from previously experienced mortality patterns was indi-lm cated. flormally only the red navigation lights are used at night.
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In both cases, birds may not have been aware of the large structure 1
l beneath the lights, since they, especially in adverse weather, do l not illuminate the tower wall itself.
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Gunn (1972) suggested that diffuse lighting, rather than glar-I ing lights should be used end that the obstacle be lighted by red,
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orange, or blue light (Gunn 1972). With low-level diffuse light, birds would not be attracted and become disoriented or blinded and unable to find their way out of the dangerous zones. Observations at the lighthouse on the German Island of Felgioland illustrate this relationship. Before Werid War I mortalities of migrating birds were extremely high, and occasionally thousands of birds were killed in a single night. The birds were blinded by the strong light source and did not see the dark, unlit walls around or beneath the lamps. After several additior.al low-wattage lamps, which illu-minated the concrr.te structures of the building, were installed, mortalities were drastically reduced.
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In recent times additional street lamps are also contributing to the visibility of the concrete lighthouse tower at night (F. Goethe in,litt.)
The International Peace Monument on South Bass Island (Lake Erie), a few miles away from the Davis-Besse plant, now 1. t lighted during migration periods and hos negligible kills. This is in con-i trast to the past when the tower had been flood-lighted.
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The declining mortalities, recently observed at the Davis-Besse Nuclear Power Plant, seem to agree with these observation pctterns.
l Most mortalities occurred at the cooling tower, especially after the construction lights were removed. Af ter that time the tower was relatively dark. After the completion of the Unit I structures and the installations of many safety lights around these buildings in fal? 1978, mortalities dropped considerably. ,A further reduction in fall mortality (1979) may be associated with the recent change to the more powerful high-pressure sodium-vapor lights.
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References
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Avery, M.L., P.F. Springer, and il.S. Dailey. 1978.
Avian mortality at man-made structures: an annotated bibliography.
I U.S. Fish and Wildl. Serv. FWS/0BS-78/58:108pp.
Belton, P. 1976.
I Effects of interrupted light on birds.
National Research Council of Canada, Field Note 73:12pp.
Crawford, R.L. 1974.
Is Bird casualties at a Leon County, Florida TV tower:
September 1973.
October 1966-Bull. Tall Timbers Res. Sta. 18:27pp.
Gunn, W.W.H. 1972.
An examination of the bird impact problem at the Nanticoke plant I of the Ontario Hydro Electric System, phase II.
Environmental Research Associates, Toronto. 15pp.
Autumq 1972.
I Hoskin, J. 1975.
Casualties at the CKVR TV tower, Barrie Nat. Can. 4(2):39-40.
Jackson, W.B., M. Temme, and W.A. Peterman. 1977.
Semi-annual report, Davis-Besse bird hazard monitoring contract.
Bowling Green State University, Bowling Green, Ohio 43403. 21pp.
Kemper, C.A. 1964.
A tower for TV, 30,000 dead birds.
Audubon Mag. 66(2):86-90.
Mudge, J.E. and R.W. Firth, Jr. 1975.
Evaluation of cooling tower ecological effects - an approach and
,I case history.
American Nuclear Society, 21st Annual Meeting, June 12, New Orleans.
! Pentecost, E.D. and I.P. Muraka. 1976.
An evaluation of environmental data relating to selected nuclear power plant sites - the Three Mile Island nuclear station site.
,3 Div. of Environ. Impact. Stud., Argonne Natl. Lab, Argonne, 111.
l5 Rep. No. ANL/EIS-4:8pp.
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' g' Rybak, E.J., W.B. Jackson, and S.H. Vessey. 1973.
- 5 Impact of cooling towers on bird migration.
Proc. Sixth Bird Control Seminar, Bowling Green State University: 187-194.
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Solman, V.E.F. 1976.
Aircraft and birds.
Proc. Seventh Bowling Green Bird Control Seminar, Bowling Green State University:83-88.
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I Stevenson, H.M.
Fall r.ligration: Florida region.
Audubon Field flotes 10(:):19-22.
1956.
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Stevenson, H.M. 1958.
Fall migration: Florida region.
Audubon Field t'otes 12(1):21-26.
Stoddard, H.L., Sr. 1962.
Bird casualties at a Leen County Florida TV tower, 1955-1961.
Bull. Tall Timbers Res. Stat. 1:94pp.
Stoddard, H.L. Sr., and R.A. florris. 1967.
Bird casualties at a Leon, County, Florida TV tower: an eleven-year I study.
Bull, of Tall Timbers Research Sta. 8:104pp.
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Table 1. flumber of birds recovered at Davis-Besse Nuclear Power I Station site during the spring and fall seasons from 1972 - 1979.
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1972 4 5 1 10 l 1973 34 4 6 44 1973 56 47 -
103 1974 117 11 48 176 1974 279 52 8 339 1975 24 16 17 57 1975 125 15 15 155 1976 43 8 11 62 1976 183 22 2 207 1977 40 6 E 48 1977 131 20 -
151 1978 70 8 -
78 1973 65 6 -
71 1979 16 2 -
18 1979 35 - -
35 I Total 344 55 84 483 Total 670 167 26 1071
% 71.2 11.4 17.4 100.0 % 82.0 15.6 2.4 100.0 I
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CT = Cooling tower i
ST = Unit I structures MT = Meteorological tower l
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I TABLE 2 Families represented in birds recovered at Davis-Besse Nuclear Power
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plant site during the spring and fall migration periods from 1972-1979.
SPRING SPECIES 1973 1974 1975 1976 1977 1978 1979 TOTALS %
Kinglets 1 0 9 5 3 1 1 20 4.1 Warblers 20 122 20 34 15 53 5 269 55.7 Finches 11 14 9 7 5 2 2 50 10.4 Mimids 6 6 0 4 1 1 1 19 3.9 Others 6 32 18 12 13 20 9 110 22.8 I Unidentified 0 2 1 0 11 1 0 15 3.1 TOTALS 44 176 57 62 48 78 18 483 100.0 FALL SPECIES 1972 1973 1974 1975 1976 1977 1978 1979 TOTALS %
Kinglets 1 40 91 33 53 17 7 4 246 23.0 l Warblers 7 38 178 98 119 98 43 25 606 56.5 U Finches 0 2 9 8 6 8 3 0 36 3.4 Mimids 0 1 0 0 0 1 0 0 2 0.2 Others 2 6 48 16 27 14 8 5 126 11.8 Unidentified 0 16 13 0 2 13 10 1 55 5.1 TOTALS 10 103 339 155 207 151 71 35 1071 100.0 lI I
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I TABLE 3
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Comparison of birds killed at the Davis Besse Nuclear Po"inr Plant
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between spring (1973 1979) and fall (1972 - 1970) sencons. Only ~
bird specics with at least seven mortalities in citber season are summarized.
Species no. of birds no. of birds ctatistically in r.orinn in fall significant 9 difference, E I
Brown Creeper 2 6 I Catbirds Golden-cror.ied Kinqlet Ruby-crowned KineTlet 13 19 1 92 154
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Philadelphia Virca 6 12 **,
Red-eyed Virca 35 38 Black- and -white iarbler 17 10 Tennessee ?larbler 19 14
'lW Mashville 'llarbler 27 37 Yellow .crbler 12 3 ***
i Magnolin ?larbler 40 105 +++
Black-throcted Blue 'larbler 4 14 ,+,
Yellow rumped larbl.cr 13 14 I 81ac! -throated Grenn 71arbler Chestnut-sided wrbler 11 3 7C 13
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Dav-breasted forbitr 7 EC *++
Glackocll .larblcr 2 38 e + .,
"inc '!nrbler 2 7 Ovenbird 16 74 Yellowthroat 40 106 e+e Canada 'larbler 1 7
- ililson 's larbler 0 0 .v + +
Annrican Rndstart 20 PC Swamp Snorrow 7 17
- Song Sparron 9 7
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sinnific,nt di fforrnce {P< C.05)
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W M M M M M M M M M M M M M M M M m m TABLE 4. Sunrnary of necropsy examinations of Davis-Besse site avian mortalities fall 1972 - fall 1979 Site or type of injury FAMILY HEMATOMA Ort HEAD HEMATOMA CRUSHED FRACTURES BILL FLECK fl0 N0. BIRDS
- light heavy on breast skull tibio- tarso-wing injury broken signs examined tarsus meta-tarsus Ardeidae 1 1 Rallidae 7 1 1 1 2 2 1 8 Scolopacidae 1 1 Laridae 1 1 1 Columbidae 3 3 1 1 6 Picidae 4 1 1 1 5 Tyrannidae 7 1 1 1 2 11 Hirundinidae l 1 Corvidae 1 1 Sittidae 1 2 1 3 Certhiidae 1 5 1 6 Troglodytidae 4 5 1 1 10 Mimidae 6 2 1 1 1 9 Turdidae 8 5 1 1 1 13 Regulidae 114 86 2 14 12 50 1 15 215 Sturnidae 1 1 1 Vireonidae 41 34 2 4 8 3 3 3 4 79 Paru1'idae 389 166 1 30 47 5 32 113 8 26 581 Icteridae 5 1 1 2 3 11 Thraupidae 1 1 Fringillidae 32 17 3 6 6 3 1 1 50 Ploceidae 1 1 2 Total s 626 327 10 40 81 5 60 177 17 53 1016
- a single bird may be cited in one or more columns
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- l 30 Ruby-crowned Kingle t l n = 19 n = 154 I
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1 APR 10 20 30 10 M AY 20 30 9 JUN SEP 7 17 27 OCT 7 17 27 i
l 30-Q Golden-crowned King le t I n=1 n = 92 20-I 10
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g \g i i 1 10 20 30 10 20 30 9 28 7 17 27 7 17 27 APR MAY JUN SEP OCT Fig. 1. Distribut;on of mortalities of (A) Ruby-crowned Kinglets, (B) Golden-crowned Kinglets, in the spring (1973 - 1979) and fall (1972 - 1979) migration seasons at the Davis-Besse Nuclear Power Plant.
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I A Bay-b reas ted Warbler l 10 n= 7 n= 58
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I B Nashville Warbler
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s 28 7 17 27 7 17 27 20- C Red-eyed Vireo n= 35 n=3B i i i i
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l 1 APR 10 20 30 MAY 10 20 30 9 JUN 28 7 SEP 17 27 OCT 7 17 27
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Fig. 2. Distribution of mortalities of ( A) Bay-breasted Warblers, (3) Nashville Warblers, (C) Red-eyed Vireos in the spring l (1973 - 1979) and fall (1972 '379) migration seasons at the Davis-Besse Nuclear Power Plant.
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,l M agnolia Warbier -
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n = 40 n = 105 I
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'l APR M AY JUN SEP OCT I B g Yellow thro a t 30 n=40 n =106
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10 20 30 10 20 30 9 19 28 7 17 27 7 17 27 APR MAY JUN SEP OCT g
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13*/ 54 % 4% 0%
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I Fig. 4. ( A) Mean frequency of bird mortalities by quadrants at Davis-Besse cooling tower for the spring periods 1974 - 1978.
(B) Mean frequency of bird mortalities by quadrants at Davis-Besse cooling tower for the fall periods 1973 - 1978.
The fall 1977 is excluded, since the most birds were found floating in the tower base.
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