Feather Forensics: tracing Australian parrot trade with stable isotopes and citizen science

Native Australian parrots are highly desired as pets in global and domestic pet trade, due to their wide range of colours and sizes, ability to mimic human speech and songs, and high intelligence. To get a new pet parrot to add to the family, buyers would generally purchase a bird through an aviary, where the bird was most likely captive-bred. However, in some cases, the bird may have been taken from the wild (wild-harvesting). This practice is legal and sustainable for some species, provided the birds are harvested responsibly, and the seller has the correct permits and documents.

However, wild-harvesting of many native Australian species is illegal, unsustainable, and may contribute to the decline of wild populations. Some species are notoriously difficult to breed in captivity, so a seller may illegaly wild-harvest a bird, but sell it as “captive-bred”.  While there are laws in place to prevent this practice, there are currently no tools available to quickly and reliably identify if a bird has been illegally wild-harvested. This puts our vulnerable native species at risk, while buyers looking for a new parrot member of their family may be fined forunknowingly purchasing an illegaly harvested bird. 

Tracing origins with stable isotopes and citizen science

Stable isotopes are a case of you are what you eat: the stable isotopes in an animal’s tissue reflects its diet and environment. We hypothesised that captive and wild birds of the same species would have distinctly different diets, which would reflect in the stable isotopes of their feathers.

For this project, we used feathers collected by citizen scientists through the Feather Forensics. We focussed on the species which had the most feathers collected: Eolophus (galahs), and Cacatua (cockatoos). 

Final results

This work is currently in peer review, and will be available to read soon. In the meantime, this work formed a part of Dr Katherine Hill’s PhD thesis, which is available online.