What is Ontario Doing?
To prevent this unwanted invader from coming into the province, Ontario has regulated all 28 species of snakehead, including Northern Snakehead, as prohibited under the Invasive Species Act, 2015.
For more information on the Invasive Species Act and Regulations, visit www.ontario.ca/invasionON.
The Northern Snakehead is a predatory fish native to southern and eastern Asia that is now found in several American states. This invasive fish was likely introduced to the United States by people who bought live snakehead from fish markets or pet shops and later released them into lakes, rivers, or ponds. The Northern Snakehead is a voracious predator that lives in lakes, ponds, rivers, and streams in water temperatures ranging from 0° to 30°C. It has been reported to travel on land for short distances by wiggling its body forward. Additionally, it possesses a lung-like organ, which enables it to absorb oxygen by gulping air while out of water or near the surface of the water. This trait allows it to thrive in water that has low dissolved oxygen levels and to even survive out of water in moist conditions for up to four days. The Northern Snakehead has been dubbed the ‘franken-fish,’ because of its reptile-like behaviour, aggressive eating habits, and its mouth full of long, sharp teeth.
Outside of its native range, Northern Snakeheads have established breeding populations in the states of Virginia, Maryland, Pennsylvania, and New York. Small numbers of fish have been found in several other states.
Impacts of Northern Snakehead
The Northern Snakehead could spread throughout the Great Lakes watershed and seriously threaten native fish and invertebrate populations in Ontario, if it is given a chance to establish.
- The Northern Snakehead has no natural enemies in North America, although Ontario’s predatory fish (e.g. Muskellunge, Northern Pike, Largemouth Bass, etc.) would predate on juvenile Northern Snakehead, it would quickly outgrow their mouth size.
- Northern Snakehead eats native zooplankton, fish and fish larvae, amphibians, invertebrates, insects, small reptiles, and even small birds and mammals.
- The Northern Snakehead’s ability to eat a wide range of foods and live in varied conditions, allows it to compete with many native fish for food and habitat.
- Because the Northern Snakehead is highly adaptable, it is likely to thrive in Ontario’s waters.
How to Identify Northern Snakehead
The Northern Snakehead can grow up to 85 cm long and weigh as much as 7 kg. With a narrow, torpedo-shaped body, and a long dorsal (back) fin, Northern Snakehead look similar to Ontario’s native Bowfin (Amia calva), and Burbot (Lota lota). Check the chart below to know if you have a Snakehead, a Bowfin, or Burbot.
- Enlarged scales on head
- Single long dorsal fin
- No bony plates on underside of head
- Pelvic fins closer to head compared to bowfin
- Anal fin almost as long as dorsal fin
- No eyespot on caudal peduncle (tail)
- Single long dorsal fin
- Bony plate (gular plate) present on underside of head
- Pelvic fins at mid-body
- Short anal fin
- Eyespot on caudal peduncle (tail)
What You Can Do
- Learn how to identify Northern Snakehead and how to prevent the introduction or spread of this unwanted species.
- Never buy or keep live snakeheads. It is against the law to keep a Northern Snakehead or any member of the snakehead family as a pet, use it as bait, or have a live snakehead in your possession.
- Do not release any live fish into Ontario lakes or rivers. If you are fishing and incidentally catch a Northern Snakehead, you must destroy it. Do not return it to the water.
- If you have any information about the illegal importation, distribution, or sale of live snakehead, report it immediately to the MNRF at 1-877-847-7667, toll-free anytime. You can also call Crime Stoppers anonymously at 1-800-222-TIPS (8477).
- If you’ve seen a Northern Snakehead or another invasive species in the wild, please contact the toll-free Invading Species Hotline at 1-800-563-7711, visit EDDMapS Ontario, or search for the ‘Invasive Species in Ontario’ project on iNaturalist.org to report a sighting.
OFAH/OMNRF Invading Species Awareness Program. (2021). Northern Snakehead. Retrieved from: www.invadingspecies.com.
This factsheet may be reproduced for non-commercial purposes.
Header photo & Northern Snakehead illustration © Joe Tomelleri
Bowfin & Burbot illustrations by New York State Department of Environmental Conservation
Think you have seen an invasive species?
Invading Species Hotline