Cause of Death of a Flammulated Owl
Cause of Death of a Flammulated Owl.--0n September 8, 1946, Walton Brown and I found a dead Flammulated Owl (Otus flammeolus) on a slope forested with lodgepole pine (Pinus murrayalza) at an altitude of 9,500 feet near Jackson Lake in the Sierra Nevada of northeastern Fresno County, California. A bulky lump, which was evident in the throat of the owl, on autopsy proved to be a large long-horned grasshopper (family Tettigoniidae) . Apparently the owl had attempted to swallow this insect head first. However, one of the long jumping legs had become twisted in such a manner as to lodge across the thorax of the insect. This increased its bulk to such an extent that it was unable to pass between the two arms of the wish bone. The owl might still have survived by disgorging its recalcitrant meal. However, the grasshopper’s other legs with the abdomen formed a tangled mass which prevented this alternative and death resulted. Aside from the complications that arose, it would appear that this insect was rather large for the owl to swallow whole. It measured 3.3 cm, long by 1 cm. in diameter dried and not including the legs. However, it appears that grasshoppers and crickets are routine items in the diet of the Flammulated Owl (Jewett, Condor, 30, 1928:164; Marshall, Condor, 41, 1939:77; 44, 1942:66).
In addition to, the long-homed grasshopper the stomach contents, which were saved and later analyzed, consisted of 4 crane flies (Tipulidae), 1 caddis fly (Trichoptera), 7 moths (Lepidoptera), 1 serpent fly (Raphidae), and 11 harvestmen spiders (Phalangida).
The owl was prepared as a study skin. Since it had apparently been dead for several da.ys, minor decomposition prevented the determination of its sex.--KARL W. KENYON, Mills College, Oakland, California, December 17,1946.