Tortoise Tales #37 (2025)

All the latest news on the tortoises’ biology, including a recent study on incubation methods. Tortoise Tales 37 2025

All the latest news on the tortoises’ biology, including a recent study on incubation methods. Tortoise Tales 37 2025
Tortoise Tales 36 2024 – Celebrating 20 years of advocacy and education!

Learning about the WST with the Year 5 students. Cathy Levett took questions from the children and grouped them according to topic, then answered them as follows.
Q: How fast do they move? How fast are they in the water / on land?
Not very fast on land but when they get to the water they can quickly swim into the plants and disappear.
Western Swamp Tortoises are reptiles so they are ectothermic (cold blooded). This means that they need to bask in the sun and warm up so they can move a bit faster.
Q: How big do they grow?
A newly hatched WST is 2.4 – 2.9cm and 3.2 – 6.6g
WST are unusual because the adult males grow to be bigger and heavier than the female.
Males – up to 15.5 cm and 550g
Females – up to 13.5 cm and 410g
Q: Can you explain how their shell gets bigger?
The shell of the WST is part of the skeleton and so it grows as the skeleton grows. The scutes on the shell peel away to make way for larger scutes.
The parts of the shell are called:
CARAPACE – the hard upper shell
PLASTRON – flat lower part of the shell
Q: What do they eat?
Information on Gooseberry Hill Research page by the children
Diet (what they eat and drink)
Carnivores that eat small invertebrates; tadpoles, mosquito lavae, frogs, dragonfly nymphs, ostracods, beetle larvae, damselfly larvae, worms.
Q: Why do they live in one place? Why don’t they stay in the water for long?
WST have special needs for where they live. They live in and near ephemeral swamps which are wet in winter and dry in summer. They have clay or sand over clay soils. When the swamp dries out the tortoises move away from the swamp area and go underground until the swamps fill with water and food again. They do this so that they can survive without food through all of the dry months.
Q: Aestivation: How does it feel when they are aestivating? How do they live underground? How will they breathe when they aestivate?
While they are aestivating, it is like they are in a very deep sleep and their breathing slows down. Although they are underground, they get air from the spaces between the soil particles.


Community Engagement & Education – Cathy Levett
With the encouragement of educator Cathy Levett (Vice-chair of the Friends group), Year 5 student Jennifer Wilcox recently sent us the activity book she created, which we will be sharing via the website and Facebook.
We’ve previously featured All Because I Crossed the Road by student Rachael Wu. Another student, Neeve Blackham-Jennings, also wrote and illustrated the award-winning Wally’s Way Home, which is available to buy through our website and also the WA Naturalists’ Club. Cathy is very pleased to be able to mentor these young authors.


The latest news from the Friends group is now available here

In addition to losing much of their habitat on the Swan Coastal Plain, our tortoises face the additional threat of climate change, as the seasonal swamps they inhabit will hold water for increasingly shorter periods of time. Recovery of the western swamp tortoise depends on securing and drought-proofing high-quality habitat in their indigenous range (in particular in and around Ellen Brook NR) and exploring new conservation options that account for future climate change.
One of these options is assisted colonisation – the intentional translocation of species outside their indigenous range to mitigate a threat – and has been explored as an option for the swamp tortoise by a team at the University of Western Australia (UWA) for over a decade. Assisted colonisation trials to wetlands near the south coast began in 2016, with juveniles bred at The Perth Zoo. These southern wetlands have longer hydroperiods than those near Perth, but are also cooler, and are expected to offer ideal microclimates for western swamp tortoises in about 20 years. Juveniles fared particularly well in a small trial wetland near the township of East Augusta, and grew comparable amounts to those released at Moore River National Park in the same year. See the full story here
Protecting habitat in City of Swan

The Friends of the Western Swamp Tortoise became aware of an Amendment (132) to be presented to the City of Swan late last year concerning Ellen Brook and Twin Swamps Nature Reserves.
Our Chairperson, Jan Bant, addressed the Councillors at an Agenda meeting on 10 November 2021, speaking on the impact likely if the buffer zones were changed. The situation became critical after 5th February 2021, when 90% of the Ellen Brook NR, habitat of the last truly self-sustaining population of the tortoises, was burned. Most areas were totally burnt out, including our restorative revegetation plantings, and only black ash remained.
Any potential development in the buffer zones (the Amendment proposed modifying the minimum lot size from 8ha to 2ha) would have had a detrimental impact on the area.
See how things turned out here