Kingfishers in paradise: the breeding biology of Tanysiptera sylvia at the Iron Range National Park, Cape York

Abstract

We describe the breeding biology and site fidelity of the buff-breasted paradise kingfisher (Tanysiptera sylvia), which migrates each year from New Guinea to breed in north-east Australia. In a three-year study at the Iron Range National Park in Cape York, Australia, we collected data from 91 breeding attempts (49 territories), and banded 77 adults and 101 nestlings (47 broods) to determine site fidelity. Paradise kingfishers arrived at Iron Range when the first major rains fell after the dry season. They nested exclusively in terrestrial termitaria, avoiding mounds that were too small, too close to a neighbouring territory, or mounds where the termites were absent. They were single-brooded, but laid a second clutch if their first attempt failed early. Clutch size was usually three, incubation lasted 25 days, nestlings hatched asynchronously and fledged after 27 days. Of 114 nestlings, 48.2% were male. Each breeding territory produced an average of 1.5 fledglings per year. The main factors influencing nesting success were predation, which ended 33% of all attempts, and brood reduction, which affected 24% of nests. Hatch failure was rare (3.2%). Birds were sexually mature at one year. Nearly half of the breeding adults banded in the first year of the study were still alive two years later, making them at least four years old. The return rates of banded adults varied among years (56–84%), but were similar for the two sexes. Returning birds almost always settled on the same territory with the same partner as the previous year, thus they formed long-term pair-bonds. In all, 7% of breeding pairs were assisted at the nest by an additional male, who was probably not their offspring.