Interrelationships of Ruffed Grouse 199 



The foxes probably warrant the title of "number one grouse 

 enemy" over most of the Northeast. In the northernmost range they 

 may sometimes be displaced by the goshawk, and in occasional 

 localities by the great horned owl. Their leading position derives 

 from their adeptness at taking grouse in all stages from the egg to 

 the adult. As a nest predator they are by far the most destructive, 

 and as an enemy of adult grouse they are outranked only by the 

 homed owl and, in the northern range, by the goshawk. They are 

 unimportant as destroyers of young grouse in summer, although 

 they do take some. 



Our experience indicates that a fox is not only a connoisseur of 

 grouse eggs but is also quite skillful in finding them. On one occa- 

 sion an observer had been placed in a house built in a tree at some 

 distance from an incubating grouse to make a twenty-four-hour 

 record of her activities. Near dawn on one morning a red fox was 

 observed at some distance coming through the woods. It disappeared 

 from sight and returned to view several times as it coursed the cover 

 back and forth a-hunting. Gradually it approached closer to the 

 observer and likewise closer and closer to the setting grouse. In 

 time it came to within a few feet of the hen, and she flushed with 

 the usual whir of leaves. The fox sprang after her but missed and 

 ran swiftly in the direction the bird had disappeared. Presently it 

 returned to approximately the place of action and with deliberate 

 efficiency sniffed the base of every tree and stump in the vicinity 

 until it found the nest of eggs. 



That fox knew what it was doing. It obviously had flushed grouse 

 before, had eaten grouse eggs before, and knew the relation be- 

 tween them. We had evidence that a single fox broke up seven 

 grouse nests in a woodland of about two hundred acres in one spring. 

 Whether or not this particular evidence may be taken as the full 

 truth, it is certain that the fox as a species is a rather efficient nest 

 hunter and that some individuals become particularly adept. On 

 the other hand, I recall a grouse that successfully brought off a 

 clutch of eggs vdthin fifty feet of a red fox den in active use. The 

 fox kits had played within twenty feet of the setting hen as evi- 

 denced by bones and skin of kills that they had dropped there. 

 That did not seem to indicate predatory efficiency. 



Foxes consistently destroy more grouse nests than do any other 

 predators in New York. The proportion of all grouse nests taken by 



