Common name: Little Bustard
Scientific name: Tetrax tetrax
Taxonomy: Order Gruiformes, Family Otididae;
Phenology: Resident species
Threat status:
National Vulnerable (Red Book of the Vertebrates of Portugal)
Global Near Threatened (IUCN)
Abundance:
National 20.000 individuals
Global 240.000 individuals (excluding the population of Kazakhstan)
Characteristics:Medium sized bird with a length between 40 and 45 cm and a wingspan between 105 and 115 cm. It weight between 700 and 950 grammes, being that the females are slightly smaller than the males.They present sexual dimorphism.The males have a greyish head, a black and white collar on the neck and a very white belly. When flying it produces a very characteristic whistle caused by the wind as it passes through the primary feathers. The females are more brownish along the dorsal part, have a thin neck and the belly is of a mottled white.The juveniles are similar to the females.
Feeding:Leafs, flowers, stalks, seeds and invertebrates.
Social behaviour:They occur in flocks during the year and disperse in the spring.
Breeding:The males defend territories in determinate locations – Leks, where they perform the courtship.The courtship involves a calling and a leap with a sibilant wing-flash.The females visit these areas and select a male to mate.The nesting occurs in fallow lands or crops, where the female lays 3 to 4 eggs on the ground, among the vegetation. After a 20 days incubation period the hatchlings appear and immediately leave the nest.During their first two weeks of life their feeding consists exclusively of insects.
Threats:The main threats to the species are agriculture intensification and the increase of human pressure.Factors like the disappearance of fallow lands, the increase of cattle density, afforestation of farming areas, increase of irrigated crops and proliferation of roads and power lines lead to the destruction and fragmentation of their habitat. Farm mechanization and the use of pesticides cause an increase of egg, hatchling and juvenile mortality.