EASTERN EVENING GROSBEAK 225 



grosbeaks, remnants of large flocks that visited us during the winter, 

 were observed in voracious day-long feedings on cankerworms in the 

 tops of large oaks in front of the Sanctuary headquarters. The gros- 

 beaks spent more time helping to clean up cankerworms than they did 

 at the feeders, where the sunflower seeds became a minor attraction," 

 From analyses of stomach contents of Canadian evening grosbeaks, J. 

 McGugan (MS.) states: "The animal matter of the bird's diet con- 

 sisted of individuals of Coleoptera, Araneida, and perhaps others. The 

 average amount of this material consumed was low but whole meals 

 were enjoyed when the supply was plentiful." 



Salted sand and gravel are sought both summer and winter. The 

 birds are seen often in summer eating cinders on railroad beds tasting 

 the salt-impregnated dirt on gravel roads that have been spread with 

 calcium chloride to allay summer's dust, or to melt ice in the winter. 

 Many casualties from cars result from their craving for salt. 



An important summer food is the wild cherry, which is fed to the 

 young before they leave the nest. To the cherry groves they are 

 taken as soon as they can fly. The cherries are eaten even before they 

 are ripe, and cherry pits are sought for on the tree and later on the 

 ground until the supply is exhausted. Evening grosbeaks do not 

 swaUow berries whole, as do robins and cedar waxwings, but always 

 break them, and their massive beaks accomplish this feat with ease. 

 A flock may be traced to a wild cherry grove by the sound of the 

 mandibles crushing the cherry stones. They always discard the 

 fleshy part of the fruit, but swaUow a certain amount of crushed shell 

 with the kernel, which probably helps them digest their food. 



Behavior. — Evening grosbeaks appear affable and harmonious when 

 not overcrowded or short of food. When the conditions are reversed, 

 they are not so attractive. Mr. Bent comments: "Although evening 

 grosbeaks are ordinarily gregarious and sociable, feeding harmoniously 

 when scattered openly on the ground, their behavior is quite different 

 when crowded on the feeding trays. There they are often selfish, hostile, 

 and belligerent, pushing their way in, sparring with open beaks, and 

 threatening to attack or drive out a new arrival. They are bosses 

 of the tray and are intolerant of other species, driving away even the 

 starlings; only the blue jay seems able to cope with them. Even the 

 females of their own species are not immune to attack by the males. 

 But, so eager are they for their food, that the tray remains crowded 

 full of birds as long as there is standing room. Towards human 

 beings they are usually tame and fearless; we can almost walk among 

 them when they are feeding on the ground; with good treatment they 

 might learn to feed from our hands, or aUow us to pick them up by 

 hand from the feeding tray. When taken from traps, they should 



