Venomous animals in Wisconsin
The ones that need the most respect: timber rattlesnake. A bite from any of them is a medical emergency.
- 1 dangerous
- 2 medically significant
Where they turn up in Wisconsin
- None recorded
- 1 species
- 2
- 3 to 4
- 5 or more
Venomous snakes in Wisconsin
Timber rattlesnakeDangerous126 records, 7 counties
Eastern massasaugaMedically significant87 records, 7 counties
Venomous snakes in Wisconsin: map, photos and look-alikes
Venomous spiders in Wisconsin
Venomous spiders in Wisconsin: map, photos and look-alikes
When they are out
- Venomous snakes
- Venomous spiders
Recorded, but not living here
- Rare records Western diamondback rattlesnake 3 open records
- Rare records Copperhead 1 open record, latest 1954
- Rare records Brown recluse 1 open record
A rare record means someone found or reported the animal once or a few times, but there is no known population. Many are strays, pets or hitchhikers in cargo.
Quick answers for Wisconsin
- Lives here Rattlesnakes
- Rare records Copperheads
- Not here Cottonmouths
- Rare records Brown recluses
- Lives here Black widows
Questions
How many venomous snakes live in Wisconsin?
2 species: Timber rattlesnake and Eastern massasauga.
Are there brown recluse spiders in Wisconsin?
Only as rare records. GBIF holds 1 open record of the brown recluse from Wisconsin, but there is no known population.
Are there scorpions in Wisconsin?
No. There are no open records of native scorpions from the state.
When are venomous animals most active in Wisconsin?
Most open records from Wisconsin fall in May, September. Records follow when people are outdoors too, so treat this as a guide, not a rule.
What should I do after a bite or sting?
Call 911 for any venomous snakebite or a severe reaction. For spider bites and scorpion stings, call Poison Control at 1-800-222-1222, free and open 24/7.