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Bright Lights Destroy Migrating Birds 
By PAvuL H. LoBIk 
EVERYONE KNOWS THAT moths and other insects have a weakness for 
flying into bright lights, often to their doom. But it was not realized until 
recently that migrating birds have the same tendency, and that the results 
can be just as disastrous. For this reason, the fixed beacon of the Empire 
State Building has been turned off during the fall migration. 
The plan of a number of women’s clubs to raise a great illuminated 
cross, 500 feet high, on top of the highest hills in Southern Illinois, is 
viewed with concern by many bird-lovers. If the illumination on this 
monument is great enough to attract and blind passing birds, then it may 
well become a symbol of destruction rather than devotion. 
Mass mortalities of birds around bright lights were first reported in 
September, 1948 (Wilson Bulletin, No. 61, pp. 86-90). It was soon dis- 
covered that ceilometers at airports were the worst offenders. A ceilometer 
is an intensely bright, narrow light, about 25 million candlepower, which 
is directed vertically near the edge of an airport at the cloud ceiling so 
that its altitude may be measured. On overcast nights, a mushroom of 
light is formed at 50 to 200 or more feet and this bright spot lures many 
birds dangerously low. During fall migrations especially, when many birds 
are riding southward on a cold front, conditions are perfect for bringing 
the migrants down into the bright cone of light, where they become con- 
fused, collide with buildings or each other, and are killed. 
Articles in the Wilson Bulletin (Vol. 66., pp. 207-215, Sept. 1954) and 
The Migrant, journal of the Tennessee Ornithological Society (Vol. 25, 
No. 4, December, 1954) summarize the reports of mortality around 
numerous air fields in the South during the past five years. In some cases, 
3 to 100 birds were killed; but at Maxwell Air Force Base, 18,000 to 
20,000 dead birds were estimated, and at Savannah, Ga., the count ex- 
ceeded 25,000. Altogether, 69 different species have been found dead, 
ranging from Grebes and Bitterns through the sparrow family; those most 
commonly killed were Red-eyed Vireos, Oven-birds, and Tennessee Warblers. 
Mr. James Tanner, editor of The Migrant, in a letter on October 18, 
1955 to Miss Florence Cummings of the I.A.S., wrote that: ‘‘Airports at 
Knoxville and Nashville, Tenn. are experimenting with special hoods for 
their ceilometers to see if these can be used to protect migrating birds. 
It is too early to know of any results.” The U. S. Weather Bureau has 
now notified all airports that ceilometers could be turned off if birds started 
concentrating in the light. This has been done a number of times at 
southern airports, and observers report that the birds, instead of fluttering 
wildly in the light beam, quickly regain their sense of direction and go on 
southward. This has resulted in marked reductions in bird mortality. 
When the ceilometers are turned on again, half an hour will elapse before 
dangerous concentrations of birds appear. 
The experiences of our southern neighbors might indicate some steps 
that we can take to reduce bird destruction around airfields and brightly 
illuminated structures. 4835 Wabansia Ave., Chicago 39 
