Breeding biology of Crimson Finches (Neochmia phaeton) in the eastern Kimberley, Western Australia

Many species show pronounced differences in life-history traits, from the individual level to divergences between distinct populations. Understanding the variation in these traits provides not only an insight into individual fitness but also essential information for the management of wild populations. Despite their popularity in aviculture and importance for captive research, our knowledge of many Estrildid finches in the wild is limited. Here we detail the breeding behaviour of 12 discrete colonies of Crimson Finch (Neochmia phaeton) in the east Kimberley region of Western Australia over two breeding seasons, and contrast our findings with studies on populations occupying different habitats. We found that many aspects of Crimson Finch breeding biology were consistent across site and studies. However, in our populations, adult survival was lower and group sizes were larger than has been reported elsewhere. We also examined age and sex differences in nestling care and found weak support for age or sex differences in feeding rates. We briefly discuss these findings in relation to theories of colony formation. These findings may help explain the evolution of colonial breeding in this species, as well as having implications for long-term ecosystem management.