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Location of breeding warrens as indicators of habitat use by maras (Dolichotis patagonum) in Península Valdés, Argentina

Authors:
  • Instituto Patagónico para el Estudio de los Ecosistemas Continentales (IPEEC-CONICET)
  • Instituto Patagonico para el Estudio de los Ecosistemas Continentales (IPEEC-CONICET)

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We characterized the habitat use by maras (Dolichotis patagonum) on a microhabitat scale in the area surrounding the warren, assessing the conditioning effect of the warren over space use and exploitation of other resources. We evaluated the relationships between the probability and intensity of use, habitat configuration and distance to the warren, counting feces along transects departing from each warren. Our results showed that the location of breeding warrens was positively associated with the habitat use by maras on a microhabitat scale. The core area of the annual activity of maras was concentrated around the warren and there was no evidence of alternative areas of activity. According to the fitted models, maras used microhabitats with a high proportion of bare soil and close to infrastructure elements. The spatial autocorrelation components indicated that intensively used patches are small and disperse. The patterns of habitat use observed in this study suggest that maras use multipurpose areas including the breeding site and resources needed throughout the year. These patterns suggest that warrens are good all year-round indicators of mara habitat use and spatial ecology.
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... Within each macroplot we searched for mara warrens following the protocol described in Alonso Rold an et al. (2015). We used warrens as indicators of the habitat selected by maras because there is evidence that they remain within an 800 m radius home range all year long (Alonso Rold an and Baldi, 2016;Taber and MacDonald, 1992b). Thus, the areas within-macroplot used by maras were defined by an 800 m buffer around warrens. ...
... The patterns of habitat use at the broader landscape scale are consistent with the patterns observed at microhabitat or fine scale where the intensity of use was related to the proportion of bare soil and the proximity to human infrastructure (Alonso Rold an and Baldi, 2016). In general, these results on habitat utilization and their role in predator avoidance agree with previous studies conducted at microhabitat scale (Kufner and Chambouleyron, 1991;Rodríguez, 2009;Taber and MacDonald, 1992b). ...
... Whilst in Peninsula de Valdés precipitations are concentrated between May and September corresponding to the months of cold temperatures. From August to December the ambient temperature increases, being this period the season for breeding (Soriano and Sala 1984;Alonso Roldán and Baldi 2016). Food availability directly affects reproduction in numerous taxa (Hamilton and Bronson 1985;Gittleman 1988;Cumming and Bernard 1997;Schlund et al. 2002;Persson 2005). ...
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