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bioRxiv · 10.1101/2020.09.21.306027

Perch selection of three species of kingfishers at the Pantanal wetland, Brazil

Contreras Peinado, L.·Ortega, Z.
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Abstract

Animal movement and behavior depend on the distribution of resources on the habitat. Therefore, individual animals are constantly making decisions on resource selection based on different attributes of the resource or its associated environmental variables. For fish-eating birds as kingfishers, selecting a suitable perch can report many benefits, as improving fishing success or reducing predation risk. Nowadays, not only natural structures, as branches, are available for birds to perch but also artificial ones, as electric lines. Thus, we aimed to understand which variables drive kingfishers perch selection, including the potential effect of its anthropic origin. We studied perch selection of three species of kingfishers inhabiting the Pantanal of Miranda of Brazil: Megaceryle torquata, Chloroceryle amazona and Chloroceryle americana. They feed in temporary ponds that are rich in trophic resources, where they have both natural and artificial potential perches. We hypothesized that artificial perches could be strongly selected, as they are more stable than natural ones and go through the ponds, providing a long surface to select optimal conditions. We assessed how kingfishers are selecting perches based on four ecologically relevant traits: (1) being artificial or natural, perch height, (3) distance to the water, and (4) plant cover. We used a resource selection function (RSF) approach to quantify the effect of these variables in the probability of presence of kingfishers. The artificial origin of a perch was independent of the probability of selection for the three species. Furthermore, birds acted randomly to the other studied variables, except for individuals of C. amazona, which select higher perches, above 3.20 m. We discuss the implications of these results for understanding the behavioral ecology and use of space of neotropical kingfishers, and how this affects their vulnerability to human habitat alterations. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=194 HEIGHT=200 SRC="FIGDIR/small/306027v1_ufig1.gif" ALT="Figure 1"> View larger version (58K): org.highwire.dtl.DTLVardef@6bc8d1org.highwire.dtl.DTLVardef@4d4d0dorg.highwire.dtl.DTLVardef@fdb9aborg.highwire.dtl.DTLVardef@1a88b15_HPS_FORMAT_FIGEXP M_FIG C_FIG

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Contreras Peinado, L., Ortega, Z.. 2020-09-22. Perch selection of three species of kingfishers at the Pantanal wetland, Brazil. https://doi.org/10.1101/2020.09.21.306027

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