Colour ornamentation in animals is exceptionally diverse, but some colours may provide better signals of individual quality or more efficient visual stimuli and, thus, be more often used as sexual signals. This may depend on physiological costs, which depend on the mechanism of colour production (e.g. exogenously acquired colouration in passerine birds appears to be most sexually dichromatic). ...

Understanding of ecosystem structure and functioning requires detailed knowledge about plant–animal interactions, especially when keystone species are involved. The recent consideration parrots as legitimate seed dispersers has widened the range mechanisms influencing life cycle many plant species. We examined interactions between burrowing parrot Cyanoliseus patagonus two dominant algarrobo tr...

The effects of providing ultraviolet (uv) radiation (285 to 315 nm, ultraviolet B) on calcium metabolism in two groups of 20 healthy grey parrots (Psittacus e erithacus) fed either a seed or pellet-based diet were investigated. There was a significant increase in the concentration of ionised calcium in the plasma of both groups, independent of the calcium and vitamin D(3) content of the diets f...

Background and Research Aims: Habitat amount plays an important role in determining the presence abundance of bird species modified landscapes, whereas habitat fragmentation has shown little effects. Toucans (Ramphastidae) parrots (Psittacidae) are large-bodied primary consumers among most representative birds Neotropical forests. They highly sensitive to loss; nevertheless, their response been...

Fleming, T.H.. Williams. C.E. Bonaccorso, F.J. & Herbst, L.H. 1985. Phenology, seed dispersal, and colonization in Muntingia calabura, a neotropical pioneer tree. Am. J. Bot. 72: 383-391. Forshaw. J.M. 1989. Parrots of the World, 3rd (revised) ed. Willoughby: Lansdowne Editions. Galetti, M. 1993. Diet of the Scaly-headed Parrot (Pionus marimiliani) in a semideciduous forest in southeastern Braz...

A total of 130 faecal samples were collected from various breeds of parrots. Eighty eight samples were found positive for single or mixed infection of Heterakis gallinae and Ascardia galli. Faecal samples were examined for counting of egg/gram of faeces using McMaster egg counting technique having overall prevalence of 67.70 % with individual relative percentage as 73.86 and 26.14 respectively....