Burger 



Chapter 16 



Inland Habitat Associations in British Columbia 



After 7 days 



After 14 days 



Survival of nests (N = 10 per transect 



15 100 250 400 



Distance from forest edge (m) 



550 



Survival of eggs (N = 30 per transect) 



15 100 250 400 



Distance from forest edge (m) 



550 



Figure 5 Survival of artificial nests, each containing three quail eggs, placed at 

 eye level in trees in transects laid out at various distances from the forest edge in 

 montane western hemlock-mountain hemlock forest in central Vancouver Island, 

 1992 (data from Bryant 1994). Nest "survival" meant the nest was in good 

 condition with at least one undamaged egg, egg survival was the count of 

 undamaged eggs. 



Use of Detection Frequency to Delineate Marbled 

 Murrelet Habitat 



Standardized pre-dawn surveys provide indications of 

 relative nesting density (Ralph and others 1994). although 

 the relationship between the number of detections per survey 

 and the density of nesting pairs has not been established and 

 is likely to vary among sites and through the season (Rodway 

 and others 1993a,b). As a first approach I have compared the 

 frequency of detections among a wide range of survey stations 

 from three sources: (1) the Queen Charlotte Islands (158 

 surveys at 50 sites in 1990; Rodway and others 1991, 1993a) 



(2) a large sample of watersheds throughout most of 

 Vancouver Island (471 surveys at 151 sites in 1991; Savard 

 and Lemon in press); and (3) intensive surveys made over 

 four years (1990-1993) at 12 sites in Carmanah Valley, two 

 in the Walbran Valley and one at Nitinat Lake (Burger 

 1994). At each site (in some of the Queen Charlotte Islands 

 surveys, a site included several stations), the mean frequency 

 of detections per morning survey was calculated for the 

 period 1 May through 31 July. Occupied detections (Ralph 

 and others 1994) could not be analyzed separately since 

 these were not given in all reports. 



USDA Forest Service Gen. Tech. Rep. PSW-152. 1995. 



159 



