Factors affecting distribution and abundance of Rufous hornero (Furnarius rufus) in the Pampas Region, Argentina.

SARASOLA JOSE HERNÁN; BEATRIZ MARTÍNEZ MIRANZO; SEOANE, JAVIER

Tandil

Congreso; XVIII Reunión Argentina de Ornitología; 2019

Universidad Nacional del Centro de Buenos Aires

Species Distribution Models (SDM) have been used during the last two decades for deeping into the factors may influence in the presence of the species in a certain place. Normally, this aprroach use only presence data for modelling the distribution. In this paper, we evaluate the enviromental factors that restricte the distribution and abundance of Rufous hornero (Furnarius rufus) in the Pampa Region of Argentina. Between December and Febraury for three consecutives years (2002, 2003 and 2004) we conducted 920 points count during 15 min in 115 squares (30 x 30 km in the Universal Transverse Mercator (UTM) grid). Surveyed squares were selected with a stratified random sampling from the total of 455000 Km2 in the study area. For each point count we characterized habitat use and structure, soil texture and permeability using Geographic Information System. Also, we calculated absolute abundance with package Distance in R software. For statistical analysis, we build Zero Inflated Models with Gamma error distribution. The Rufous hornero distribution are determinated for habitat complexity structure. This structure may infuence in the optimal nesting areas (sustrato de nidificación). Low soil permeability related with puddly areas has a negative relation with the species distribution. The ausence of suiteable material for build the oven nest seens to be a reason for this relation. The Rufous hornero is more abundance in forest areas than others habitats, like crops or grassland. Nevertheles, factor related with soil characteristics may not a limited factor in the species abundance at this Regional scale.