Avifaunal community structure associated to El Conchalito mangrove, BCS, Mexico under different tide conditions

Abstract

The importance in the study of avian community structure relates to their relevant role in theecosystem. Specially, when they are exposed to collateral damage by anthropogenic activities. The goal of thisresearch was to determine the variation of avian community structure in the mangrove forest El Conchalito, BCSthrough the use of ecological indices such as diversity (H’), dominance (D), and the biological value index (IVB)in April-June of 2016 during the seasonal transition from Spring-Summer. To describe the environmental frame,measurements of temperature, noise level, and chlorophyll a were made, and other climatological data were used.A total of 15 species of aquatic, marine or shore birds were recorded (5 orders, 7 families and 9 genera), and 3species of terrestrial birds (2 orders, 2 families and 3 genera). Maximum bird abundances were observed duringthe first sampling. Diversity values varied between H´= 1.1 and H´= 1.8, with maxima at the beginning and atthe end of the study period. This was related with the low tides and the increase of species richness, respectively.Noise level and chlorophyll a concentration, were not associated directly with the changes observed in the community structure. Species richness was associated directly with temperature increase. The most important birdspecies were: Egretta thula (96.9%), Zenaida asiatica (88.7%), Numenius phaeopus (86.8%), and Egretta rufescens (83.8); less important was Ceryle alcyon (28.2). Three species protected under NOM-059-SEMARNAT-2010were identified.