( 350 ) 



ON THE POSITIONS ASSUMED BY BIRDS 

 IN FLIGHT. 



BY 



BENTLEY BEETHAM, F.Z.S. 



III. ALIGHTING. 



The act of alighting appears to be not the least difficult 

 part in the performance of flight ; indeed, whether it be 

 regarded from man's standpoint or from the bird's, it 

 may well be accounted with the most difficult. 



On a boisterous day when a bird Avishes to alight at 

 some particular point, its powers are often taxed to the 

 utmost. The obvious signs of this being so are the abrupt 

 and spasmodic turns, and the flapping of the Avings, and 

 the jerkj'^, erratic course immediately preceding the 

 alighting ; while not infrequently the clumsy and hurried 

 actions on touching the ground, plainh' show how com- 

 paratively little the flight had been under control the 

 moment before alighting. 



That this is a real difficulty of which the birds are fully 

 conscious is, I think, shown by their preparing for alighting 

 long before they actually do so. Their first care is. 

 apparently to reduce their speed as much as possible, sO' 

 as still to leave them sufficient " way " to ensure some 

 stability in the air, and some power of guidance. They 

 soar round and round or approach slowly on a long,, 

 wavering course, trailing their feet as brakes, or advance 

 in a vertical!}^ zig-zag course, finding much resistance 

 in short but steep ascents. But even after these and 

 many other preliminary devices have been tried, birds 

 often get sadly knocked about on really boisterous days 

 when alighting on the cliffs. The difficulty lies not sa 

 much in the mere act of alighting, as in the setthng at 

 some particular spot. A bird must slow up, or the impact 

 would be too great for its leg muscles to cope A\dth ; and 

 the difficulty is that when slowing up and almost at a 

 standstill in the air, so to speak, it is greath' at the mercj'- 



