About the Research

From the electric blue flash of a Splendid Fairywren chasing an intruder across the mallee to the musical twittering of Red-backed Fairywrens making their way through a garden, fairywrens are an unmistakable Australian icon. In addition to displaying a range of brilliant colors, this diverse family of birds can be highly gregarious or extremely territorial and inhabits a variety of environments across the country.

As scientists, we are quickly drawn towards these highly visible differences between species of  fairywrens. Upon seeing two different species, we immediately wonder — what drives this variation, and can we explain it? And, of course as birders, fairywrens are fun to study! Whether it’s in your backyard, or the arid interior, we all enjoy watching the drama of these beautiful birds as they flit through the underbrush chasing insects and potential mates.

Moult, sexual selection, and ecology

When it comes to mating, fairywrens are well-known across the world for being one of the most promiscuous and unfaithful groups of birds. All species for which genetic studies have been performed, engage in extra-pair matings outside of their pair bond. Both males and females will often venture outside their territory seeking potential extra-pair partners. This high extra-pair mating rate means that males have the potential to monopolize mating opportunities because females are not limited to mating with the male they’re paired with. Instead, a female can choose to mate with the male she finds most attractive. If the traits that lead to one male obtaining more matings than another are heritable, we can predict that these attractive males will produce attractive sons, and the process will repeat itself. This phenomenon is a component of the evolutionary process known as sexual selection. Given enough time, sexual selection can help shape the evolution of a species.  

When it comes to female fairywrens choosing a male to mate with, moulting into bright breeding plumage has consistently been shown to improve a male’s ability to attract females. DNA analyses have shown that in species like Red-backed Fairywrens, which breed in either dull female-like plumage or bright plumage, bright males consistently have higher mating success than dull males. In Superb and Red-winged Fairy-wrens where all or nearly all males produce the bright nuptial plumage for the breeding season, males who moult into bright plumage earliest in the winter (non-breeding season) obtain the highest mating success in the following breeding season. In addition to differences between males, we also know that for some species, differences in environmental conditions, especially rainfall, can impact the timing of moult. This means changes in the environment can impact mate choice through the onset of moult.

Studying different species across different environments can give us insight into how these species have evolved to be what they are today and how they might change as their environments change around them.

Our questions

The questions we’re currently tackling through the Fairywren Project are:

1. How do environmental conditions influence timing of molt into nuptial plumage for each fairywren species?

2. How do environmental conditions influence the size and composition of cooperative groups for each fairywren species?

3. How do the relationships we observe between environment, timing of molt, size of groups, and composition of groups within each species help us explain previously-reported variation in extra-pair paternity, helping, and dispersal across the fairywren species?

We hypothesize that environmental conditions such as rainfall, vegetation density, and insect abundance influence when males obtain bright plumage and therefore the number of males in bright plumages, which may further impact the social behavior of the birds. 

How we will answer our questions

WE NEED YOU to help us observe fairywrens! We’re looking for citizen scientist partners to help us collect observations of fairywrens and their plumages. Having your eyes on the ground will help us obtain year round data from across all of Australia. A serious twitcher or just enjoy watching birds in your garden? If you see fairywrens you can help! Visit our participate page to learn more about this fun process.

We will combine your observations with observations of environmental conditions such as rainfall and vegetation which are available from the Australian government and other monitoring organizations. This will allow us to illuminate patterns of variation in breeding plumage, timing of moult, and social group organization across Australia’s variable environment.

We hope to continue this study for a number of years to maximize our power in comparing how different environmental conditions in the same locations lead to year-to-year differences.

Go here to participate.

How we will share our results

We plan to share our results through scientific papers, and popular press articles, including periodical newsletters we’ll post on our Project News page and send out to our followers. To sign up to receive email updates from the Fairywren Project, click here.

 

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