Behind the paper: taxonomy and conservation of grassland earless dragons

I’ve used some of these photos in previous posts (here and here), but now I need to post an update. This little dragon is now known as the Monaro grassland earless dragon.

I’m excited to be a co-author on the paper, published last week in Royal Society Open Science (open access), that describes this species. This research combines several methods (phylogeography, phylogenomics, external morphology, micro X-ray CT scans) to review the grassland earless dragons of south-eastern Australia. It also shows how historic museum specimens can be important to understanding current biodiversity.

Previously considered a single species, Tympanocryptis pinguicolla, which was listed as Endangered, four species are now recognised:

  • the Canberra grassland earless dragon, Tympanocryptis lineata Peters, 1863 (the name lineata has been re-assigned – a surprise to many – reflecting the rules of taxonomic nomenclature and the uncertain origins of the specimen previously chosen as lectotype)
  • the Victorian grassland earless dragon, Tympanocryptis pinguicolla Mitchell, 1948
  • the Monaro grassland earless dragon, Tympanocryptis osbornei sp. nov.
  • the Bathurst grassland earless dragon, Tympanocryptis mccartneyi sp. nov.

For me, the most important part of this work relates to the implications for earless dragon conservation. All four species are habitat specialists with limited distributions. They rely on native grasslands, which are a threatened ecosystem. A huge proportion of Australia’s native grasslands have now been lost to agriculture or human habitation, and remaining grasslands are still threatened. So habitat loss / degradation / fragmentation are real threats to grassland earless dragons. The dragons are also at risk from climate change, because they are sensitive to drought and extreme temperatures.

Previously, we classed the grassland earless dragon as an endangered species, and there was a plan in place to manage its conservation. Now that we recognise the grassland earless dragons as four distinct species, we need to develop appropriate conservation management plans for each of these. This means that we need to understand the current status of each species, and the threats that each faces.

We know very little at all about the Bathurst species, and there are very few records from this area. Before we can effectively conserve this species, we need to understand the distribution and ecology of the Bathurst dragons, so that we can better protect them and their habitat.

We do know that the other three grassland earless dragon species have all experienced recent declines. All known populations of the Canberra species are found within a few kilometres of Canberra airport, just outside the city centre. Their grassland patches are surrounded by roads, suburbs and other urban infrastructure. The Monaro dragons are the most widespread species, but only one known location occurs within a protected reserve. Even worse, the last high quality sighting of the Victorian species was in 1969, and many of the places where this species was historically recorded are now within the the city of Melbourne.

This means that the Victorian grassland earless dragon may now be extinct, but we can’t be sure. If so, this would be the first (recorded) extinction of a reptile species on the Australian mainland since European colonisation. However, these lizards are very small and tend to hide in spider burrows, in grass tussocks, or under rocks, which makes them difficult for people to detect. In Canberra, conservation dogs have even been trained to help researchers to find them. There’s now an urgent need for a comprehensive hunt for the Victorian grassland earless dragon, as some of the potential dragon habitat around Melbourne has not been recently surveyed. So perhaps we can hope that a population has survived…

I’d like to remain optimistic for all of the grassland earless dragons: previous work on the Canberra and Monaro species shows that captive  breeding is a possibility, and if we as a society can find the motivation, we really should be able to protect remaining grassland habitats.

For those who are interested, here are links to some of the previous research on the grassland earless dragons:

* Note, the photos above show lizards being handled by a colleague. This was done during field surveys, while the animals were being weighed, measured etc., with animal ethics approval. I like to use these photos as they demonstrate the small size of the earless dragons, and make the point that their future really is in our hands. But I want to emphasise that it is usually irresponsible to catch, handle, or otherwise disturb wild animals – especially endangered species – without a really good reason and the necessary permits!

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s