594 Oluf Winge. 



Prof. Lütken having applied to Government for the 

 purpose of obtaining for identification at the Zoological 

 Museum the birds killed at lighthouses and light-vessels, 

 and of utilizing in other ways the observingopportunities 

 of hght-keepers, a preliminary inquiry was made by the 

 naval authorities (Capt. C. Normann^, R. Dan. N. 

 in Charge) as to the number of birds killed at the various 

 lights. The returns by the keepers were then placed at 

 the disposal of Prof. Lütken. They contain not a little 

 Information as to the general phenomena of birds, appearing 

 at the lights, entirely in accordance with what is already 

 known on the subject from the Reports of the British 

 Association Committee. It is often mentioned that many 

 more birds Struck a light during the earlier years of its 

 existence than later on, and it is given as the general opi- 

 nion, that the birds learn to avoid the danger. The pheno- 

 menon is really too general to allow of an explanation not 

 tending in this direction; it should here be remembered that 

 many more birds than those killed appear round the lights, 

 or even strike without becoming disabled. The reports 

 plainly show the well-known fact that lights in small lonely 

 islands, or on exposed points of land, or in light-vessels 

 at some distance from shore, generally attract most birds; 

 that the most powerful lights are included in this class, 

 should be borne in mind. At some stations of this de- 

 scription large numbers of birds are killed; at many lights 

 in the inner waters, in more or less land-locked situations, 

 nearly no birds strike. The height of lantern, within the 

 limits given here, would seem not to affect the numbers 

 very strongly; some of the most frequented lights are of the 

 highest ; Hammershus is 290 feet, Hanstholm 2 1 2, Stevns 2o3 ; 

 Hjelm is 160, Skagen 140, Anholt i 3o, the lanterns of light- 

 vessels 3o. 



The numbers given below of birds killed at the lights are 

 alvi'ays, unless otherwise stated, to denote the general number 

 of a year, roughly guessed by the keepers. Thrushes, 

 starlings, larks, redbreasts, and »unknown small birds« 

 are most often mientioned, larger birds now and then. 



