Critical protection for threatened spiny crayfish!

In early September 2023, fifteen spiny crayfish species were listed as threatened under Australia’s federal law for the environment (Environment Protection and Biodiversity Conservation Act (EPBC Act) 1999); NGT’s Maiko Lutz and Nick Whiterod (now with the Goyder Institute’s CLLMM Research Centre) coordinated the conservation assessment of more than half of the newly listed spiny crayfish species (see ‘National Threatened Species Day: Better protecting our precious native plants and animals’ for the official press release). This is a major milestone for the conservation of spiny crayfish as a listing under the EPBC Act guarantees greater protection and opens up additional funding opportunities for threatened species management. Read our previous article on our comprehensive genetic study here.

The fifteen spiny crayfish added to Australia’s list of at risk fauna are part of the genus Euastacus, which is endemic to eastern Australia, and is considered one of the most threatened genera of freshwater crayfish globally. Prior to the current listings, only three spiny crayfish species were listed under the EPBC Act. Now, almost 35% of Australia’s spiny crayfish are considered threatened with extinction under the EPBC Act. The newly added species include seven Critically Endangered species — species that are facing an extremely high risk of extinction in the wild— and eight Endangered species— species that are facing a very high risk of extinction in the wild. The threat status of another 17 spiny crayfish is currently being evaluated; if all are found to be in need of protection, the number of spiny crayfish considered at risk of extinction could almost double within the next couple of years.

The eight spiny crayfish conservation assessments coordinated by Maiko and Nick are:
• Mud gully crayfish (Euastacus dalagarbe): Critically Endangered.
• Blue-black crayfish (Euastacus jagabar): Critically Endangered.
• Morgan’s crayfish (Euastacus morgani): Critically Endangered.
• Gamilaroi crayfish (Euastacus gamilaroi): Endangered.
• Smooth crayfish (Euastacus girurmulayn): Endangered.
• Blood crayfish (Euastacus gumar): Endangered.
• Riek’s crayfish (Euastacus rieki): Endangered.
• Sutton’s crayfish (Euastacus suttoni): Endangered.

Most of these species have highly restricted distributions and are reliant on specific habitat features. For example, Morgan’s crayfish, listed as Critically Endangered, is only known from two streams that are 200 m apart within the highland rainforest of Bindarri National Park in New South Wales. The Endangered Riek’s crayfish on the other hand is restricted to the Australian Capital Territory and southern New South Wales, where it is most commonly found in streams > 1000 m above sea level that are fringed by snow gums, tussock grasses and heath.

The main processes that are threatening the survival of spiny crayfish include habitat destruction, pollution, invasive species and human exploitation. Many species have already experience drastic declines in the quality and extent of their habitat, and conditions are projected to deteriorate further under the myriad of potential impacts of climate change, such as more frequent and intense bushfires.

Almost all spiny crayfish recently listed as threatened were heavily impacted by the 2019-20 megafires that burnt more than 10.3 million hectares across southern and eastern Australia (see Whiterod et al. 2022 for an Action Plan for bushfire-impacted spiny crayfish). Up to 70% of the range of the Endangered smooth crayfish was burnt during the 2019-20 bushfires and populations might decline by as much as 50% over the next 10 years due to the impacts of climate change. The recent recognition of the threat status of spiny crayfish is therefore vital in ensuring the long-term persistence of the species and will help guide the allocation of conservation funding to where it is needed most urgently.

You can read more about our exciting conservation with other species of spiny crayfish, including returning Murray crayfish to South Australia after 40 years, and monitoring populations of threatened Glenelg spiny crayfish.

This project is supported by the Australian Government’s Bushfire Recovery for Wildlife and Habitat Program

Maiko Lutz