Angela Russell, PhD candidate at La Trobe University

When I was applying for a PhD position, the men in my family had several helpful suggestions for topics. Barramundi populations in the Northern Territory, Coral Bleaching on the Barrier Reef, Dugong health in Moreton Bay. The fact that all the ideas they came up with revolved around boats was not lost on me. I had several willing volunteers if the research involved mucking around in boats in warm climates. 

So my interest in looking at Marsupial Gut Microbiomes (sometimes referred to as gut flora) and how they can influence the fitness of hand-reared and released animals, was not warmly received by the menfolk. No boats required, and worse, the main topic of conversation for the next three and a half years would inevitably revolve around faeces. So my PhD became known as a Poo-h-D. Fortunately, I am not alone in my faecal fetish.

Any wildlife carer you meet will talk at great length about the nitty gritty of what comes out of their charges cloacas. It is a vital part of monitoring the health of their animals, and often the first indicator of illness.

If you are not closely attentive to the colour, consistency and smell of your animals poop’, you may miss the early warning signs and valuable time in starting treatment. 

So when I was looking for volunteers to collect poop from wild and captive marsupial species over a wide geographical area ranging from Queensland to Tasmania, it was mainly wildlife carers who answered the call. Particularly carers who specialise in possums, who, I was told, felt they were the forgotten group when compared to the marquee species like koalas and kangaroos. 

So I enlisted a core group of around 20 people along the east coast of our continent who, every season, dutifully went out in all weathers, armed with their forceps and ziplock bags, to select fresh pellets from their in care residents or wild animals that passed through, filled in the paperwork, carefully labelled the bags and then stored them in their freezers until they could be posted in special temperature controlled packaging to the university for genetic analysis. This would establish a baseline of what the microbiome should look like in different animals in different areas at different times of the year, enabling recognition of an imbalance in captive animals that can be addressed and prevented by changing management techniques.

To aid my communication with these wonderful people, I started a Facebook group page which became known as the Marsupial Microbiome Poop Troop 

Not impressed by the troop’s efforts is the university stores’ supervisor who receives the parcels. He must have sensitive olfactory senses as he routinely sends me emails announcing the arrival of more ‘animal excrement’. The last one was described as a ‘malodourous package’ to be collected urgently.

While it all sounds like fun and games, the research behind the collected poop has serious potential to save many lives, with a particular focus on young orphaned joeys. Whether their mothers were hit by cars or attacked by dogs, they arrive at the wildlife shelters stressed, often injured, generally cold and hungry. Because marsupials are born so undeveloped, they require an extended period of time in care when orphaned. The gut microbiome of these joeys, which are equivalent in development to premature infants, is still being established at this critical time, via the mother’s milk, environmental conditions in the pouch, cleaning and grooming. The sudden loss of this parental care, coupled with the stress of being in captivity and a complete change of diet, can do a great deal of harm to the gut microbiota, leaving the joey open to infections, diarrhoea and dehydration, which can be rapidly fatal. If it were possible to fix this imbalance, the success rate of rearing orphaned marsupials would rise, and their improved general health should mean greater numbers of animals successfully reintroduced to the wild.

While the animals involved in this study are considered ‘common’ (IUCN status least concern), the same principles may be applied to endangered species held in captive breeding programmes once it has been shown to work on the more prolific species.

Without the help of these volunteers it would have been impossible to sample so widely and consistently. The remaining poop will be kept frozen and made available to future researchers, so these poop people have, through their dedication and persistence, made a real contribution to marsupial microbiome research that will continue to help wildlife in the future. Mission accomplished Poop Troop!

Angela Russell is a recipient of a 2023 Holsworth Wildlife Endowment Grant.

Images:

Top – Dianne Lane posted the nocturnal output of one of her larger in care joeys. Impressive!

Bottom – Tracey Dodd posted this photo of a proud donor