224 U.S. NATIONAL MUSEUM BULLETIN 237 part i 



If tree buds may be considered springtime treats for the grosbeaks, 

 nature has other delicacies in store for them as well. Of their fondness 

 for wild maple syrup Thornton W. Burgess (1947) writes: "Opposite 

 the window of my room is a maple tree. Squirrels have been eating 

 the buds and when the sun warms things up in the morning the sap 

 drips from the twigs where the buds have been nipped off. The other 

 morning the sun striking through these drops of sap filled the tree with 

 glittering jewels. A male Evening Grosbeak climbed about parrot 

 fashion from jewel to jewel drinking them." Mrs. Downs writes me: 

 "our front sugar maple tree has been gashed in many places by some 

 creature. Today I saw the sap flowing from it and the EG's drinking 

 the sap! Sometimes they even had to 'tread air' to get the sap because 

 there was no branch handy on which to perch." 



As the breeding season approaches, the grosbeaks begin to seek out 

 insect food, of which the spruce budworm is an important item. G. H. 

 and H. C. Parks (1963a, 1963b) describe graphically their studies of a 

 concentration of evening grosbeaks nesting where a heavy infastation 

 of spruce budworm was damaging the forest in the Patapedia River 

 watershed of Quebec. In June 1 962 using only two 3-cell Potter traps 

 they captured 747 grosbeaks in 11 days. On the last day of their stay 

 airplanes from the Quebec Department of Forestry sprayed the area 

 with DDT. Mr. and Mrs. Parks returned the following June and, 

 using the same traps in the same manner during the corresponding 11 

 days caught only five grosbeafe. During their visit to the same area 

 in July 1964 they could not find a single evening grosbeak. Parks 

 and Parks (1965) conclude: 



To explain the dense concentration of Evening Grosbeaks which we had origi- 

 nally found at 39-Mile Camp let us call attention to the fact that repeated spray- 

 ings during several years had been employed in an attempt to gain mastery over a 

 spruce budworm outbreak which involved forests in New York, Maine, Ontario, 

 and New Brunswick, as well as in Quebec. Since the birds no longer found an 

 adequate supply of the budworm for food in the sprayed areas they moved on to 

 unsprayed tracts where the insect still persisted. 



Examination of the maps on which the sprayed regions had been plotted shows 

 that the effort to control a particularly obstinate budworm infestation near Que- 

 bec's Gasp6 had approached, but had never quite reached, the Patapedia River 

 prior to 1962. So, as this "island" of budworm-infested forest (with 39-Mile 

 Camp situated very close to its center) became smaller and smaller the concentra- 

 tion of Evening Grosbeaks which was attracted to its abundance of edible larvae 

 became heavier and heavier. Then 1962 witnessed the spraying of even this area 

 and the resultant successful elimination of the pests which had been damaging the 

 trees. Come the spring of 1963, the almost completely eradicated budworm popu- 

 lation was no longer adequate to attract and hold more than a very few of the 

 Evening Grosbeaks which might be returning to, or migrating through, this area. 



Maurice Broun, of Hawk Mountain Sanctuary, wrote Mr. Bent in 

 1952: "Last May, from the 10th to the 15th, from 20 to 40 evening 



