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Spatial distribution, prevalence and diversity of haemosporidians in the rufous-collared sparrow, Zonotrichia capensis
(2019)
Abstract
Background
Parasite prevalence and diversity are determined by the distribution of hosts and vectors and by the interplay among a suite of environmental factors. ...
Differences in circulating corticosterone levels associated with elevation of breeding sites in Rufous-collared Sparrows Zonotrichia capensis
(2020)
To facilitate breeding and any energetically costly activity, individuals of the same species can substantially vary their circulating corticosterone (CORT) levels to cope with local environmental conditions at different ...
Feeding and digestive responses to fatty acid intake in two South American passerines with different food habits
(Springer, 2014)
Specific fatty acids (FA) such as unsaturated
(UFA) and saturated (SFA) fatty acids contained in foods are
key factors in the nutritional ecology of birds. By means of a
field and experimental approach, we evaluated the ...
Geographic variation in the response to thermal acclimation in rufous-collared sparrows: are physiological flexibility and environmental heterogeneity correlated?
(BLACKWELL, 2008-06)
1. It has been proposed that habitats with low productivity, and hence low resource availability, may favour individuals with lower rates of resource use and energy expenditure. In birds, some studies have shown that basal ...
Temporal stability and change in a microgeographical pattern of song variation in the rufous-collared sparrow
(Academic Press Ltd - Elsevier Science Ltd, 2004-09)
We studied the pattern of song variation in the rufous-collared sparrow, Zonotrichia capensis, in the 1987 and 2000 breeding seasons in a 7-km 2 area covering open and closed habitats. We measured 14 quantitative song ...
Metabolic enzymes in seasonally acclimatized and cold acclimated rufous-collared sparrow inhabiting a Chilean Mediterranean environment
(Chinese Academy of Sciences, 2014)
Due to the higher energy requirements of birds during winter, it is predicted that the activities of metabolic enzymes (e.g., citrate synthase, CS and cytochrome C oxidase, COX) should increase in tandem with increases in ...
Intraspecific basal metabolic rate varies with trophic level in rufous-collared sparrows
(2009)
One of the most controversial hypotheses that associate basal metabolic rate (BMR) with food habits and habitat productivity is the food habit hypothesis (FHH). Here we examined the relationship between BMR, diet, and ...
Osmoregulatory and metabolic costs of salt excretion in the Rufous-collared sparrow Zonotrichia capensis
(Elsevier, 2013)
Recent experiments on shorebirds have demonstrated that maintaining an active osmoregulatory machinery
is energetically expensive. This may, in part, explain diet and habitat selection in birds with salt glands.
However ...