Nelson and Hamer 



Chapters 



Nesting Biology and Behavior 



Table 6 Mean time of first morning feeding visits in relation to official sunrise at Marbled 

 Murrelet nests by state 1 



1 Data from Hamer and Cummins 1991 ; Kerns, pers. comm.; Nelson and Peck, in press; S.W. 

 Singer, pers. comm. 



2 No tree nests with chicks were observed in Alaska; data from 2 ground nests in Alaska not 

 available. 



3 Data from British Columbia were not available. 



4 Does not include one late observation (104 min), assumed to be a second feeding. 



Table 7 Mean time of last evening feeding visits in relation to official sunset at Marbled 

 Murrelet nests by state 1 



1 Data from Hamer and Cummins 1991; Kerns, pers. comm.; Nelson and Peck, in press; S.W. 

 Singer, pers. comm. 



2 No tree nests with chicks were observed in Alaska; data from 2 ground nests in Alaska not 

 available. 



3 Data from British Columbia were not available. 



and Peck, in press; S.W. Singer, pers. comm.). At a nest in 

 Washington, adults rested on the nest platform an average of 

 2.2 minutes before approaching the chick with food. 



In Oregon and Washington, the chick sometimes gave 

 begging calls just prior to the adults landing on the nest 

 platform (x = 1.2 minutes before adults arrived, n = 8 

 observations at f nest) and throughout the feeding visit (see 

 vocalizations section) (Hamer and Cummins 1991; Nelson 

 and Peck, in press). At a nest in Washington, the chick spent 

 an average of 10.8 minutes begging during each feeding visit. 



After approaching the chick, the adult stands motionless 

 as the chick energetically strokes or nudges the throat and 

 beak of the adult with its beak (Hamer and Cummins 1991; 



Naslund 1993a; Nelson and Peck, in press). Adults at a nest 

 in Washington held the fish over the chick for an average of 

 9.7 minutes (s.e. = 1.4, n = 16 observations) before the food 

 transfer took place. The adults occasionally give soft whistle 

 or grunt-like vocalizations until the nestling takes the fish 

 (Hamer and Cummins 1991; Nelson and Peck, in press). The 

 time adults spent at nests during feedings ranged from 13 

 seconds to 80 minutes (x = 12.6 min, s.e. = 0.7, n = 16) 

 (Hamer and Cummins 1991; Hirsch and others 1981; P. 

 Jones, pers. comm.; Kerns, pers. comm.; Naslund 1993a; 

 Nelson and Peck, in press; Simons 1980) (table 8). Fifty 

 percent of feedings lasted > 1 1 (median) minutes. Chicks 

 held the fish 5 seconds to 2 minutes before swallowing it 



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



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