Venomous snakes and spiders in Pennsylvania
Pennsylvania has three venomous snake species among the 20 snake species listed there: timber rattlesnake, eastern copperhead and eastern massasauga. The timber rattlesnake accounts for the most records (479), and venomous species make up 9% of all 8,487 licensed snake records in the state. On the spider side, two species are medically significant: northern black widow and southern black widow.
Venomous snakes of Pennsylvania
Pennsylvania's venomous snakes are two rattlesnake species and one copperhead or cottonmouth species. Together they account for 795 licensed records; the timber rattlesnake alone has 60% of them, and the least recorded, the eastern massasauga, has 55.
Dangerous spiders of Pennsylvania
Two widow species (Northern black widow: 9 records, Southern black widow: on record, no openly licensed records to count) are on the Pennsylvania list. There is no recluse spider on the Pennsylvania list: no recluse species reaches 10 records in the state. Widow bites cause muscle pain and cramps; recluse bites can cause a slow-healing wound. Both are rare and seldom fatal.
Other snakes recorded most in Pennsylvania
These eight account for 71% of all licensed snake records in Pennsylvania; the most recorded, the common garter snake, alone for 20%.
All 20 snakes of Pennsylvania →
Other spiders recorded most in Pennsylvania
These eight account for 26% of all licensed spider records in Pennsylvania; the most recorded, the orchard orbweaver, alone for 6%.
All 164 spiders of Pennsylvania →
When venomous snakes are out in Pennsylvania
Observation records of venomous snakes in Pennsylvania run mostly May through August, peaking in July with 32% of them. December through February together hold under 2% of the records, so venomous snakes in Pennsylvania are rarely recorded in winter.
When spiders are most active in Pennsylvania
Observation records of spiders in Pennsylvania run mostly April through October, peaking in June with 17% of them. Winter (December to February) holds 2% of the records.
Counties with the most venomous snake records
Wyoming County has the most records of venomous snakes in Pennsylvania, 166, most of them of the timber rattlesnake. Allegheny County and Westmoreland County follow.
| # | County | Records | Most recorded there |
|---|---|---|---|
| 1 | Wyoming County | 166 | Timber rattlesnake |
| 2 | Allegheny County | 65 | Eastern copperhead |
| 3 | Westmoreland County | 64 | Eastern copperhead |
| 4 | Centre County | 45 | Timber rattlesnake |
| 5 | Butler County | 37 | Eastern massasauga |
| 6 | Montgomery County | 32 | Eastern copperhead |
| 7 | Susquehanna County | 26 | Timber rattlesnake |
| 8 | Cumberland County | 22 | Timber rattlesnake |
| 9 | Clinton County | 20 | Timber rattlesnake |
| 10 | Lycoming County | 19 | Timber rattlesnake |
Where in Pennsylvania are snakes recorded most?
Allegheny County leads with 864 records (10%), followed by Warren County and Westmoreland County; the top five counties hold 31% of the total. 67 of Pennsylvania's 67 counties have at least one licensed snake record.
| # | County | Records | Share |
|---|---|---|---|
| 1 | Allegheny County | 864 | 10.2% |
| 2 | Warren County | 695 | 8.2% |
| 3 | Westmoreland County | 509 | 6.0% |
| 4 | Erie County | 316 | 3.7% |
| 5 | Potter County | 278 | 3.3% |
| 6 | Wyoming County | 275 | 3.2% |
| 7 | Centre County | 239 | 2.8% |
| 8 | Montgomery County | 239 | 2.8% |
| 9 | Venango County | 205 | 2.4% |
| 10 | Forest County | 204 | 2.4% |
| 11 | Butler County | 197 | 2.3% |
| 12 | Crawford County | 193 | 2.3% |
Pennsylvania counties with their own page: Allegheny County, Bucks County, Centre County, Dauphin County, Erie County, Lebanon County, Montgomery County, Philadelphia County, Warren County and Westmoreland County.
Are there poisonous snakes in Pennsylvania?
Yes. Pennsylvania has three venomous snake species on its list, the kind people usually call poisonous: timber rattlesnake, eastern copperhead and eastern massasauga. Strictly, snakes are venomous (they inject venom), not poisonous (harmful to eat or touch).
Are there rattlesnakes in Pennsylvania?
Yes. Two species are on the Pennsylvania list: the timber rattlesnake and the eastern massasauga, with 534 licensed records between them. Most licensed records of the timber rattlesnake come from Wyoming County, Centre County and Susquehanna County.
Are there copperheads in Pennsylvania?
Yes. One species is on the Pennsylvania list: the eastern copperhead, with 261 licensed records. Most licensed records of the eastern copperhead come from Allegheny County, Westmoreland County and Montgomery County.
Are there cottonmouths (water moccasins) in Pennsylvania?
No. GBIF holds no cottonmouth record for Pennsylvania under any license.
Are there coral snakes in Pennsylvania?
No. GBIF holds no coral snake record for Pennsylvania under any license.
Timber rattlesnake (Crotalus horridus)
Pennsylvania has 479 licensed records of the timber rattlesnake, which ranks the state 1st of the 30 states where it reaches our threshold. Its observation records in Pennsylvania run mostly May through August, peaking in July; most licensed records come from Wyoming County, Centre County and Susquehanna County. Range in other states and photos: Timber rattlesnake profile.
Eastern copperhead (Agkistrodon contortrix)
Pennsylvania has 261 licensed records of the eastern copperhead, which ranks the state 6th of the 27 states where it reaches our threshold. Most of its licensed records in Pennsylvania come from Allegheny County, Westmoreland County and Montgomery County. Range in other states and photos: Eastern copperhead profile.
Eastern massasauga (Sistrurus catenatus)
Pennsylvania has 55 licensed records of the eastern massasauga, which ranks the state 3rd of the 8 states where it reaches our threshold. Most of its licensed records in Pennsylvania come from Butler County, Venango County and Crawford County. Range in other states and photos: Eastern massasauga profile.
Harmless lookalikes in Pennsylvania
Many snakes and spiders taken for venomous ones are harmless species with a similar look. These are the usual confusions, with each species' licensed records in Pennsylvania.
What looks like a copperhead in Pennsylvania
Copperheads: 261 licensed records in Pennsylvania. Harmless species often taken for them are also on the state list: northern water snake (859), eastern milksnake (520), eastern rat snake (358) and eastern hog-nosed snake (99). Together they have 1,836 licensed records, and the lookalikes are recorded 7 times as often.
What looks like a cottonmouth in Pennsylvania
No cottonmouths reach the Pennsylvania list, and GBIF holds no cottonmouth record for Pennsylvania under any license, so a snake taken for one here is most likely a harmless lookalike. Those recorded in the state: northern water snake (859).
What looks like a rattlesnake in Pennsylvania
Rattlesnakes: 534 licensed records in Pennsylvania. Harmless species often taken for them are also on the state list: eastern hog-nosed snake (99). It has 99 licensed records, and here the venomous species are the more recorded side, 5.4 to 1.
What looks like a coral snake in Pennsylvania
No coral snakes reach the Pennsylvania list, and GBIF holds no coral snake record for Pennsylvania under any license, so a snake taken for one here is most likely a harmless lookalike. Those recorded in the state: eastern milksnake (520).
What looks like a widow spider in Pennsylvania
Widow spiders: 9 licensed records in Pennsylvania. Harmless species often taken for them are also on the state list: triangulate bud spider (107), common house spider (19), twospotted cobweb spider (13) and boreal combfoot (11). Together they have 150 licensed records, and the lookalikes are recorded 17 times as often.
What looks like a recluse spider in Pennsylvania
No recluse spiders reach the Pennsylvania list, and GBIF holds no recluse spider record for Pennsylvania under any license, so a spider taken for one here is most likely a harmless lookalike. Those recorded in the state: longbodied cellar spider (34), spitting spider (8) and dark-legged grass spider (1).
How Pennsylvania compares
By count of venomous snake species, Pennsylvania ranks 20th of 50 states, level with 8 other states. Nationally, Arizona leads with 14 species; five list none.
Pennsylvania lists as many venomous snake species as New York and Ohio, and more than any other state it borders (Pennsylvania: 3 species; New York 3, Ohio 3, Maryland 2, New Jersey 2, West Virginia 2, Delaware 1).
Every venomous snake listed in a neighboring state is also on the Pennsylvania list. The most widely shared is the eastern copperhead, listed in all six bordering states.
Are there poisonous spiders in Pennsylvania?
Does Pennsylvania have black widows?
Yes. Two widow species are on the Pennsylvania list: the northern black widow (9 records) and the southern black widow (on record, no openly licensed records to count).
Does Pennsylvania have brown recluse spiders?
No. GBIF holds no brown recluse record for Pennsylvania under any license.
Northern black widow (Latrodectus variolus)
Pennsylvania has 9 licensed records of the northern black widow, which ranks the state 14th of the 30 states where it reaches our threshold. Range in other states and photos: Northern black widow profile.
Southern black widow (Latrodectus mactans)
The southern black widow is on the Pennsylvania list from records under other licenses, with no openly licensed records to count, so the state is not ranked for it. Range in other states and photos: Southern black widow profile.
Are there scorpions in Pennsylvania?
No. GBIF holds no scorpion record for Pennsylvania under any license. Every scorpion has venom; only the Arizona bark scorpion's sting is medically significant, and it is not on the Pennsylvania list.
More for Pennsylvania
GBIF records read 2026-09-29. Listed: any license. Counted: CC0/CC BY only. How we count.