136 CUl EK CHARACTERISTICS AND SHELTER REQUIREMENTS 



that nests are safer in sparse undergrowth in second-prowth hardwoods (type E). The same 

 appears likely in the open undergrowth beneath mature hardwoods and conifers (FH). But 

 the inference is not strong and is further weakened when the companion types (EH and F), 

 upon examination, are found to show this tcn(lenc\ in reverse. 



Thicket versus Open Cover as NesI Locations 



As has been seen, grouse prefer to locate their nests where the undergrowth is neither par- 

 ticularly dense nor open. Referred to above, however, is the character of the undergrowth in 

 the general vicinity of the nest rather than that actuall) at the nest site. Table 132* was 

 accordingly prepared to answer the occasionally raised question, "Is a grouse nest, without 

 benefit of immediately surrounding cover vegetation, more likely to be broken up than one 

 located in a thicket?" 



The answer seems to be that it is not. Of 630 nests with but little sheltering cover, 362 

 (57.5 per cent) hatched, whereas of 208 thicket nests, 110 (52.9 per cent) were not disturbed. 

 Since most of the nests destroyed are broken up by predators it is evident that the concealing 

 coloration of the bird and its habit of sitting close at the apjiroach of danger are much more 

 eflective shields against danger than the thickness of the cover inmiediateK surrounding the 

 nest. This is further borne out in the previous table. 



The Effect of Distance jroni an Opening:: on Nesting Success 



Investigation field men, early noticing a tendency of some predators. |)arti(iiiarly fox. to 

 follow along the edge of openings and woods' roads, considered the possibility that nests lo- 

 cated close thereto might be more subject to predation than were those located at greater 

 distances. 



Table 133^ illustrates the results of this study. The percentage of nests hatching within 

 ten feet of an opening was 53.6 per cent in comparison with 60.8 ])er cent for those located 

 over 200 feet distant. Though both totals are based on a substantial number of nests, the dif- 

 ference is not large enough to represent with certainty a valid trend though, in this situation, 

 such a one would seem logical. 



In further subdividing the number of nests hatched at various distances into the cover 

 types in which they were located, the numbers became too small to permit trends to be eval- 

 uated except by combining similar types. This done, there still seems to be no substantial 

 indication that nest mortalitv. at various distances from openings, varies markedly with the 

 type of cover. 



Since nearly half of all nests are located along woods' roads or trails, a special study of 

 such situations was made to determine whether or not nests are more likely to be broken 

 uj) when located along such trails thati in the vicinity of other types of openings. As in- 

 dicated in table 134^ of 359 nests along a woods" road or trail. 210 (58.5 per cent) were 

 not molested while of 572 near all olhci t\pcs nf (ipcnings .'^13 (51.7 per cnii I haliluil. 



• See A)il>fni)ix, [•. 797. 

 A See A|ii>fn<lix. p. 798. 

 t Scr Apprnilix. p. 800. 



AN OLD WOOn.S ROAD IS ATTRACTIVE AI.IKK TO 

 TIIK M\\ IN SKARCH OF RELAX.VTIO.N A.\D TO 

 Till-: (.liolSE SEEKING NESTING SITES NEARBY 



