Synanthropic characteristics of the cattle egret Bubulcus ibis (Linnaeus, 1758) in the Brazilian semiarid

Abstract

Cattle egret Bubulcus ibis is a highly synanthropic species, which has been benefited by the increase of livestock in recent decades. The species originates from the Old World and spread to all the continents, with the exception of Antarctica. Three current concerns of this expansion and population growth are: competition for resources or predation of endemic species, transmission of diseases to the human population and the livestock and collision with aircrafts. This study investigated a cattle egret breeding colony established at the margin of the BR-304 in the municipality of Assu, RN, Brazil. Data samplings were conducted in four tours in April and May of 2012. The authors performed censuses to estimate the total number of birds present in the breeding colony between 04:40 and 06:00 PM. They used a graduated stick of 6 meters with a mirror fixed at one end to measure the height of trees and nests and to verify the presence of eggs in the nests.