Energy and Nutrient Use during Moult by White-Crowned Sparrows Zonotrichia leucophrys gambelii

Abstract

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Leukocyte profiles indicate nutritional, but not moulting stress in a migratory shorebird, the Common Snipe (Gallinago gallinago)

“…Third, corticosterone increases protein mobilization (i.e. breakdown), which may interfere with elevated protein requirements during moult (Murphy and King 1992;Romero et al 1998). This is in agreement with the results of our study, indicating no significant variation in H/L ratios between successive stages of moult, as well as between moulting and nonmoulting Common Snipe.…”

Body building and concurrent mass loss: flight adaptations in tree sparrows

“…Yet, an important conclusion is that slow moult most probably does not increase predation risk due to impaired predator evasion. However, moult is an energetically costly period (Murphy & King 1992;Lindstro« m et al 1993), and if moulting birds' foraging rates increase to comply with enlarged physiological demands, they may face an increased risk of predation due to increased exposure (cf. Witter & Cuthill 1993).…”

Molt–breeding overlap alters molt dynamics and behavior in zebra finches,Taeniopygia guttata castanotis

“…Even if the metabolic costs of producing a feather were relatively low (Ankney, 1984;Murphy and King, 1986;Buttemer et al, 2003;Hoye and Buttemer, 2011), the total amount of energy required during the molting period is expected to be increased because of a combination of protein requirements for feather synthesis and increased costs of flying (Murphy and King, 1992;Lindström et al, 1993;Murphy and Taruscio, 1995;Schieltz and Murphy, 1995;Murphy, 1996;Swaddle and Witter, 1997;Fox et al, 2008;Strochlic and Romero, 2008). Indeed, even though zebra finches in our study reduced feather growth rate quite dramatically and slightly reduced aspects of molt intensity during the overlap, they also increased their feeding rate by as much as 80% and lowered preening by approximately 70% compared with individuals that only molted.…”