24 



BIRDS OF A MARYLAND FARM. 



ness that Tvould have been creditable in a flycatcher. Swifts and a 

 variety of swallows, including the tree swallow, the bank swallow, the 

 rough-winged swallow, the barn swallow, and the purple martin, 

 appeared to feed on May -flies exclusively. WheneA'er a kingbird 

 dashed into a tree these birds would fl}" b}^ the dozen to the spot and 

 seize the fluttering, helpless insects that had been dislodged. When, 

 however, a gust of wind drove the May-flies before it, the swallows 

 were seen to best advantage as they circled gracefulh^ after them. 



Field observations and the examination of stomachs proved that 40 

 species had eaten May-flies, but this number probably represents onh' 

 about half the truth. Not many birds were collected at the height of 

 the insects' abundance, because even casual observation showed that 

 practically all the birds of the farm, not only the highly insectivorous 

 species, but also the species chiefly f rugivorous or granivorous, turned 

 to them for food. The following is the list obtained: 



List of birds known to have fed on May-flies. 



Green heron. 



Woodcock, 



Spotted sandpiper. 



Yellow-billed cuckoo. 



Black-billed cuckoo. 



Downy woodpecker. 



Chimney swift. 



Kingbird. 



Great crested flycatcher. 



Phoebe. 



Wood pewee. 



Blue jay. 



Common crow. 



Bobolink. 



Red-winged blackbird. 

 Orchard oriole. 

 Crow blackird. 

 English sparrow. 

 Field sparrow. 

 Cardinal. 

 Purple martin. 

 Barn swallow. 

 White-bellied swallow. 

 Bank swallow. 

 Eough-winged swallow, 

 Cedar bird. 

 Red-eyed vireo. 

 Parula warbler. 



Yellow warbler. 

 Black-poll warbler. 

 Water-thrush. 

 Maryland yellow-throat. 

 Yellow-breasted chat. 

 Wilson warbler. 

 Redstart. 

 Catbird. 

 House wren. 

 Carolina chickadee. 

 Blue-gray gnatcatcher. 

 Grav-cheeked thrush. 



Though May -flies furnish valuable food for fish and do no harm to 

 crops, they are of course a plague when they become so numerous. 

 Broadly considered, however, their consumption by birds is a misfor- 

 tune, for it suspends or prevents the destruction of really injurious 

 insects. At no other time do all birds eat so large a proportion of 

 insect food, for at no other time do they find such a scarcity of other 

 suitable food, and if their attention were not diverted b}- this easy and 

 palatable pre}^ they might be expected to do the best of their work 

 against insect pests. This unfavorable condition is, however, strictly 

 local, lasts only a few da3^s, and would not occur on areas remote from 

 large bodies of fresh water where the May -fly breeds. 



INFESTED CROPS. 



At each visit the crops were inspected for pests, and whenever any 

 crop had sufiered appreciably it was regularly watched to see whether 

 birds came to its relief. Stomachs were collected also around the 

 infested fields. 



