1 6 MIGRATION DATA ON CITY HALL TOWER. 



been picked up, the number on any one night varying from one to one 

 hundred and fifty-four birds, thirty-two species being found in one 

 night's slaughter. A Red-tailed Hawk for a time made his home in the 

 tower and has carried away a number of birds. There were also no 

 doubt many birds lost among the numerous projections and lodging 

 places on the tower and roof below, while others were picked up by 

 strangers, cats, dogs, etc., in the streets and court. 



My purpose in keeping these notes was not with any hope of discov- 

 ering something new, but light-house or rather high-tower collecting 

 was a novelty to me, and I was ready to record anything startling or 

 interesting. Incidentally I have found it a most convenient, as well as 

 fairly accurate, way of observing the fall migration without losing any 

 time in the field, and believe the results have not been unprofitable. 

 The electrician of the tower would merely push the button and the 

 lights would do the rest. The weather data was taken from the news- 

 papers, adding special notes as on the severity of the weather, sudden 

 changes of temperature, moonlight, etc, etc., which struck me at the 

 time as affecting the flights and number of victims. 



In 1897, during the fall observations, nearly the whole month of Sep- 

 tember was clear and few birds were led astray into the light, and only 

 thirty struck between August 23rd and November 8th. In the spring 

 of 1898 Penn's collection only amounted to six birds. In the fall, the 

 first two weeks of September were so warm that there was practically no 

 migration until the 15th, when it was sudden and soon over, netting 

 thirty-one victims. 



This present year (1899) the great clock, with an illuminated face 

 over twenty-five feet in diameter, made its appearance, but luckily for 

 the birds, the lights around the tower were turned off from May 2 to 16, 

 and all the birds escaped but ten. 



This fall, however, the great parade and the Industrial Exhibition 

 were special occasions for illumination, when four festoons of lamps 

 were swung from the rim of Penn's hat to the balcony, and the gleanings 

 from August 23rd to October 31st amounted to four hundred and fifty- 

 two birds. If, like the light-houses, there was a cylinder of glass 

 around the outside of the light this slaughter would have been enor- 

 mous. As it is, many of the birds approach the tower without striking, 

 and I have watched them fly between the lights, circle the tower and 

 then disappear into the darkness without in the least endangering their 

 lives. 



The theory that the old birds pass south earlier than the young does 

 not seem to compare favorably with the line of specimens obtained from 



