The Canberra grassland earless dragon is a rare sight, with estimates suggesting that only around 100 individuals remain in their natural habitat. Protecting this unique species is imperative for its survival.
Ryan Colley, a PhD student at the University of Canberra, has been researching the genetics of these dragons since 2020. He noted that spotting them outside of their burrows is quite challenging. “You might see one darting about occasionally, but it’s quite infrequent,” he explained.
To enhance the chances of survival for these small reptiles, researchers have created artificial burrows using clay.
According to Ben Croak, the dragon recovery coordinator for ACT Parks and Conservation, the grassland environment poses significant threats to such a diminutive creature, particularly due to extreme heat. “In the summer months, the grasslands can be extremely hot,” Dr. Croak remarked. “We’ve recorded surface temperatures soaring to 70 degrees Celsius, which is lethal for a small dragon.”
The natural nesting sites for the dragons are typically spider burrows. The new terracotta tubes are designed to replicate these burrows, as they are positioned approximately 20 centimeters below the surface. “The ground offers insulation, and being buried around 20 centimeters creates a thermal gradient that allows the dragons to move up and down to find their preferred temperature,” Dr. Croak noted.
While PVC tubes have been previously employed for monitoring purposes, Dr. Croak pointed out that they are not suitable for egg-laying. The moisture-retaining properties of clay are expected to mitigate the effects of climate extremes and assist in egg incubation.
A video showcasing an earless dragon burrow has been released, highlighting these efforts. Dr. Croak mentioned that the trial aims to assess the effectiveness of the new burrow designs before the upcoming hot season. “Like many creatures, they will take advantage of suitable habitats when available,” he added.
In total, 100 custom-made dragon dens have been established at two locations in Canberra, providing the reptiles with a variety of burrowing options. “They have quickly taken to the new burrows, which was somewhat unexpected,” Mr. Colley shared. “It was encouraging to see them prefer these natural-looking burrows over the PVC alternatives.”
Using an endoscope, Mr. Colley has been actively monitoring the usage of the new burrows. “When we observe them inside, they are typically coiled up at the bottom,” he reported.
Creating these burrows presented its own challenges. Dr. Croak recounted the difficulty in finding someone to produce a bulk order of 100 tubes, each 20 centimeters long and designed to be thin yet structurally sound. “The artistic constraints involved in making simple clay tubes did not appeal to everyone,” he explained. However, Strathnairn Arts in North Canberra embraced the project and efficiently produced the required tubes. “We greatly appreciated their willingness to take on this task,” he added.
Tom, an artist from the workshop, has joined the team to witness the installation of his creations in the field.
While providing adequate shelter and nesting sites is vital for the conservation of this critically endangered species, it is not the only hurdle. The populations of dragons in the Australian Capital Territory (ACT) are small and fragmented. Mr. Colley, who also works with the Office of Nature Conservation, highlighted this concern. “These populations are becoming increasingly genetically isolated from one another, even though they exist within relatively close proximity,” he stated. He emphasized that the initial step toward addressing this issue involves translocating individuals between different sites to enhance genetic diversity.
