Dr Prykes Ponderings!

Fiery redheads rule the roost!!

Many people have shown an interest in the scientific research we are doing on the Gouldian finch. We hope that by keeping you informed we can repay some of the much appreciated support. In this first scientific newsletter, I will explore some of our recent research on the behavioural, physiological and genetic differences between the three head colour varieties (morphs) with regards to dominance. Not only does understanding how individuals compete for access to limited nest sites and food help us to understand the dynamics in wild populations, as you will see, understanding dominance is also crucial for effectively housing and breeding Gouldian finches in aviaries.

by Dr Sarah R. Pryke

 What does this mean for breeders?

These findings have a number of important implications, which will hopefully be useful for owners and breeders of Gouldian finches. 

First, to maintain healthy, stress-free populations (i.e. multiple birds in a single cage), red-heads should be kept at lower densities than either black-heads or yellow-heads. It is important to note that variation in ‘stress’ is not an easily measurable index (without specific blood and hormone assays), but ultimately, stressed birds are more susceptible to pathogens, parasites and disease, and therefore are more likely to get sick. When breeding birds in large populations it is particularly important to keep red-heads at lower densities, because breeding increases the normal stress load placed on all birds – and this effect is exaggerated in red-heads.

             Second, for breeders keeping mixed populations of Gouldian finches, it is important to get the balance between red-heads and black-heads right. We know that red-heads and black-heads respond very differently to aggressive environments: red-heads are very sensitive and become highly stressed at high densities, whereas black-heads are more passive and appear to be buffered against these social
stressors. As a guide, mixed populations should contain no more than 30% red-heads. In fact, this is the frequency of red-head birds observed in wild populations (with black-heads making up 70% and the rare yellow-heads less than 1%) and is by the far the most successful breeding frequency across our large population-based studies……………..

Gouldian finches (and probably a number of other birds) characteristically attack from above and will not aggressively displace their opponents from a vertically lower position. As a consequence, dominant males typically occupy and defend the highest perch, nest box or position in an aviary. This means by simply looking at which bird spends most of their time on the top perch or breeds in the highest nest box, you will be able to identify the dominant birds. There are ways to aid birds in establishing a stable dominance rank by helping them to quickly and effectively establish a dominance hierarchy – contrary to expectations; this will actually reduce (rather than increase) aggression within a population. For example, individuals who can simply signal their relative dominance status by where they perch or nest within a cage will substantially reduce the number of aggressive conflicts and fights needed to establish their dominance status……….
 

Future research plans:
This newsletter outlines some of our findings regarding dominance, and in the next few issues we will report on other behavioural research, such as mate choice, imprinting and parental care, as well as aspects of nutrition and diet. Our work on the wild populations in the Kimberley is also continuing (with great success) and over the next year we will report on the threats and current management plans for these endangered populations. We also have big plans for the next few years (in some new and very exciting areas) and they will no doubt be of interest to all Gouldian finch supporters and breeders – we will continue to keep you up to date with our research on this amazing little finch.

Dr. Sarah R. Pryke is a Research Fellow in the Centre for the Integrative Study of Animal Behaviour (CISAB) at Macquarie University

 
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