566 ANIMAL LIFE IN TEE YOSEMITE 



adult insects which take shelter in the furrows in the bark. Probably the 

 smaller sized nuthatches and creepers obtain, on the average, 'bugs' of 

 smaller caliber than are sought out by the woodpeckers. The bill of the 

 creeper is a more delicate instrument than that of the nuthatches. Its 

 slender curved form makes possible to the bird a farther reach, into the 

 narrowest of crevices where small insects lurk. 



A creeper moves only upward on the trees, whereas the nuthatches run 

 about without reference to direction, and go up, down, or crosswise seem- 

 ingly with equal facility. The short tail of a nuthatch is always carried 

 in line with its back and gives the bird no support such as the creeper 

 obtains from its longer and stiff-pointed tail. The nuthatches have long 

 toes provided with stout, well-curved and sharp-pointed claws, and these, 

 catching in small irregularities in the bark, enable the birds to cling 

 readily, whatever their position with reference to the pull of gravity. The 

 bill is straight, rather strong, and sharply pointed, and serves equally 

 well in pulling insects out of crevices, hacking open nuts or seeds, and in 

 excavating or enlarging nesting holes in rotten wood. 



Nuthatches usually keep rather closely to their distinctive mode of 

 foraging; yet on one occasion, at Chinquapin, May 20, 1919, a Slender- 

 billed Nuthatch was observed capturing flying insects. The bird was 

 clinging 25 feet above the ground on the trunk of a tree, facing downward 

 but with its head turned outward almost at right angles with the trunk. 

 Upon sighting a passing insect the nuthatch would dart out, with undulat- 

 ing flight resembling that of a small woodpecker. Its tail was spread so 

 that the marginal white spots showed plainly. With this short but broad 

 'rudder' the bird seemed to be able to change direction easily while pur- 

 suing its winged prey. Upon making a capture the nuthatch would alight 

 upon some nearby tree, run along until an appropriate place was found 

 and then, turning head downward, would pound the insect until it was 

 in condition to swallow. Four or five perches within a 50-foot radius 

 were occupied thus during the few minutes that this bird was under 

 observation. 



On the same date and at the same place another Slender-billed Nut- 

 hatch was watched as it foraged about the bases of the fir trees and on 

 the ground. It seemed rather incongruous for this bark searcher to 

 descend and cross the needle strewn earth between adjacent trees. The 

 bird visited fifteen or so trees and fallen logs during as many minutes 

 but seemed to have no fixed forage beat as these were not visited in any 

 regular sequence. Rarely did the bird go far above the ground; its 

 highest excursion was not over 15 feet. On the fallen logs it worked just 

 as on standing trunks and if it disappeared from sight its travels soon 

 carried it back into view again. 



