NOKTHERlsr RED-SHOULDERED HAWK 185 



Day once found a nest a foot out from the trunk of a pine in a 

 cluster of twigs and small branches, a very unusual and insecure 

 location ; but the same nest was used again 10 years later ! This same 

 pair once built in a red cedar. 



The nest of the red-shouldered hawk is usually well and firmly built 

 and securely placed on a solid foundation, so that it lasts for a num- 

 ber of years. I believe the hawks prefer to build a new nest each 

 year, as they usually do so ; occasionally we have found them using 

 the same nest for two, or even three, years in succession; oftener 

 they return to the old nest after a lapse of two or more years. 

 Whether the nest is robbed makes very little difference; I have 

 known a pair to raise a brood successfully for three years in suc- 

 cession in the same nest and then abandon it the next year for no 

 apparent cause. On the other hand, I have known a pair to use 

 the same nest three years in succession, including a second set one 

 season, although the eggs were taken each year. Occasionally red- 

 shouldered hawks use nests built by other species; I have never 

 found them using an old crow's nest, but they sometimes alternate 

 with barred owls; we have three times found them using old nests 

 of Cooper's hawks, and they often build over old squirrels' nests; 

 in four cases we have seen a gray squirrel run out from the lower 

 portion of an occupied hawk's nest. Probably the hawks seldom 

 molest these large squirrels ; once we found the hawk's eggs broken, 

 for which the squirrels may have been to blame. 



About the first week in March, in a normal season, our red-shoul- 

 dered hawks begin repairing their old nests, or building new ones, 

 about a month or more before the first eggs are laid. If an old nest 

 is to be used it is plainly marked thus early in the season with a 

 fresh sprig of pine, hemlock, or cedar, as a sign that the owner has 

 claimed possession. Nest building is a deliberate process, lasting 

 four or five weeks, and sometimes nests are built that are never used. 

 One pair, or possibly an unmated bird, has for several years built a 

 nest that was not used ; one year they built two nests, using material 

 from the first, which was a fine large nest, to build the second, a 

 quite inferior nest ; although I flushed the bird off this second nest, 

 no eggs were ever laid in it. 



The nest of the red-shouldered hawk is usually recognizable as 

 a substantial, well-built structure, filling the crotch to a considerable 

 depth and rather flat on top. It is usually smaller than a redtail's 

 nest, which it resembles otherwise, but it differs from the nests of the 

 Accipiters in containing much more soft material, and it is larger 

 than the carelessly built nest of the broadwing. It is usually well 

 decorated with bits of white down, which increases as incubation 

 progresses; more or less down is also scattered about in the woods 



83561—37-^13 



