Native to Europe and Asia, the Chinese weatherfish was introduced into Australia as an ornamental fish. Also known as Japanese weatherloach, oriental weatherloach or weatherfish, they are found in natural waterways due to being released from aquariums or escaping from ornamental ponds.
Chinese weatherfish is a restricted noxious fish under the Biosecurity Act 2014.
- Japanese weatherloach
- oriental weatherloach or weatherfish
- Small, elongated and cylindrical.
- Small eyes.
- Usually mottled yellow-brown with black spots and a pale underside.
- Easily seen black spot at the base of the tail fin.
- Covered in mucus, making them very slippery to handle.
- 10 barbels (whisker-like organs) around their mouth.
- Spine concealed in their skin.
- Grows to about 25cm.
- Unusual ability to absorb oxygen through their gut/intestine and exhale through their anus.
- Freshwater fish.
- Cold-water, benthic (bottom-dwelling) fish commonly found in slow flowing or still water.
- Prefers to live on sand, mud or detritus substrates (debris layers) into which they can burrow.
- Sedentary (inactive) and nocturnal (active at night).
- Often found in highly-vegetated areas as they prefer soft light.
- Tolerates low oxygen and uses atmospheric oxygen in extreme conditions.
- Can also survive in very dry conditions.
- Originates from China.
- Occurs naturally in parts of Siberia, Korea and Japan.
- Previously a popular aquarium fish but importing was banned in 1986.
- Feral (wild) populations exist throughout New South Wales, Australian Capital Territory and Victoria.
- Sexually mature at around 10cm.
- Lays eggs on aquatic vegetation or mud during the summer.
- Not egg guarders.
- Multiple spawners and can lay over 4,000 eggs per spawn.
- Worms, small crustaceans, insects, insect larvae and small aquatic organisms.
- Competes with native fish for food and space.
- Introduces disease and degrades habitats.
- Can survive where native species find it too degraded.
- Good invader e.g. high reproducer, flexible diet, tolerate broad environments and low vulnerability to predators due to burrowing.
- Continues to spread in south-eastern Australia due to irrigation and illegal use as bait fish, as well as without aid.
Monitoring and action
- If you catch Chinese weatherfish in the wild, humanely kill them and do not return them to the water. Report all invasive fish captures through our online reporting form. Take photos, if possible, to show your catch.
- Follow the ethical euthanasia code in Euthanasia of animals used for scientific purposes (PDF, 1.8MB), the 2001 Australian & New Zealand Council for the Care of Animals in Research and Teaching publication. The most appropriate way may be to stun the fish with a sharp blow to the back of the head, just above the eyes. When done correctly, this causes brain destruction—the fish's gill covers should stop moving and eyes should remain still.
- Intensive fishing may reduce pest fish numbers in small enclosed waterbodies, but this practice alone is very unlikely to be effective for long-term control.
- Poisons can completely remove pest fish in ponds and small dams but are not practical for rivers and streams, as these poisons also kill native fish.
- Chinese weatherfish is a restricted noxious fish under the Biosecurity Act 2014.
- You must not keep, feed, give away, sell, or release them into the environment without a permit.
- If you catch these species, you must immediately humanely kill and dispose of them responsibly away from the waterbody.
- By law, you have a general biosecurity obligation (GBO) to take reasonable and practical steps to minimise the risks associated with restricted noxious fish under your control.
- Contact our Customer Service Centre
- Pest fish information
- Report a pest fish
- FishBase—a global information system on fishes
- Last reviewed: 14 Dec 2018
- Last updated: 14 Dec 2018