Murray River Crayfish (Euastacus armatus)
Description
- The Murray River Crayfish is the second largest freshwater crayfish in the world.
- It's also known as the Murray Crayfish, Murray Lobster, or Murunung (Ngunnawal names provided by the Winnagay Ngunnawal Language Group).
- They grow up to 50 cm long and weigh up to 2.7 kg.
- They can live for over 30 years. Mature females mate in May.
- They can carry up to 1,500 eggs under their tails during winter.
- They release their babies in late spring or early summer.
- These crayfish tend to live in larger rivers and large streams and sometimes in lakes.
- They burrow between boulders and cobble and use tree 'snags' for protection.
- They feed on woody debris, biofilms, leaf litter, fish, and animal carcasses.
- They shred woody and leafy debris to help the aquatic nutrient cycle.
Find out more about the Murray River Crayfish on Canberra NatureMapr.
Where to find them
The species lives in the southern Murray–Darling Basin below about 700 m above sea level.
In the ACT and surrounds, it can be found in the:
- Enlarged Cotter Reservoir and lower Cotter River
- Tumut River
- Goobragandra River
- lower Goodradigbee River.
They are no longer found in the Molonglo, Queanbeyan and Yass rivers.
Conservation threats
Freshwater crayfish across the world are under threat. Their major threats are:
- habitat destruction
- over extraction of water
- river changes
- overfishing
- introduced species
- disease
- barriers across rivers
- climate change.
Conservation status
- Australian Capital Territory – Vulnerable (Nature Conservation Act 2014).
Conservation actions
Conservation actions aim to:
- replant trees along the Murrumbidgee River as part of the Million Trees program
- improve the water quality and habitat waters in the Murrumbidgee River through the Upper Murrumbidgee Demonstration Reach initiative
- Improve passage and habitat through the Murrumbidgee River, for example past Tharwa, by installing rock groynes and log jams.