Noon-Day Feeding of the Pacific Nighthawk
Noon-day Feeding of the Pacific Nighthawk
At midday, June 2, 1934, I was hunting along Indian Creek, some two miles southeast of Riddle, Owyhee County, Idaho. The sky was clear. The full rays of the summer sun had caused a subsidence in the activities of the birds, save for two Pacific Nighthawks (Chordeiles minor hesperia). They were actively zig-zagging over the creek, evidently in pursuit of insects. To me they seemed out of place. One male, now number 619 in my private collection, came within range of my gun and I collected it. I was curious to see what the bird, had been feeding on at that time of day; so the stomach, well gorged with insects, was preserved.
Upon my return here, Dr. Edwin C. Van Dyke, Professor of Entomology at the University of California, kindly identified the insects with the following results:
Predaceous water beetles: Colymbites sp., numerous; Agabus sp. one or two.
Water scavenger beetles: many Tropisternus lateralis; many Enochrus sp. and other small species; many Sphaeridum scurabaeoides, a manure feeding species.
Burying beetles: Silpha bituberosa, a single specimen.
Dung beetles: one Aphodius fimetarius and two Aphodiue vittatus.
Rove beetles: one Creophilus maxillosus villosus.
Grasshoppers: one hind leg of Melanoplua sp.
To sum up, the food of this nighthawk, at the time it was shot, consisted of aquatic and scavenger beetles and one grasshopper.
William B. Davis
Museum of Vertebrate Zoology, Berkeley, California, February 8, 1935