Waterbird Populations in the Brisbane Region, 1972-83, and Correlates with Rainfall and Water Heights

Abstract

Mean numbers and annual variation of 52 species of waterbirds (families Podicipedidae; Pelicanidae; Anhiigidae; Phalacrocoracidae; Ardeidae; Ciconiidae; Plataleidae; Anatidae; Rallidae; Jacanidae) from the Queensland Ornithological Society's records of the Brisbane region during 1972-83 are presented. Changes in the numbers of many species showed significant negative correlations with changes in the Moreton winter rainfall (3 months before the count). Changes in numbers of hardheads, grey teal and Eurasian coot also had significant negative correlations with changes of inland rainfall, and many other species showed similar trends. Changes in numbers of darter and pied cormorant were positively correlated with changes in Moreton and Warrego rainfall respectively. Most species had non-significant correlations with Moreton dam levels, but for chestnut teal, white-faced heron and dusky moorhen these approached statistical significance (P<0.1). Numbers of whitefaced heron, black swan, comb-crested jacana and darter decreased, and those of Australian pelican and plumed and wandering whistling-ducks increased during the survey period. The coastal and inland distribution of some species is also presented.