Catching and Monitoring Timber Rattlesnakes in Pennsylvania
Pennsylvania Fish and Boat Commission biologists hunt and capture Timber Rattlesnakes to perform basic assessments. They look for injuries, measure the snakes, determine their sex and tag them to monitor them in the future.
We get excited when we hear that. There are different theories on why rattles evolved. So large ungulates — deer, bison, elk — wouldn’t tramp on them. It’s also affiliated with a nasty bite. Animals that have experienced the bite hear that and they get freaked out. They’re going to move away.
- Chris Urban, chief of the PFBC’s Natural Diversity Section
Managing Timber Rattlesnakes
The buzz of a rattlesnake rattle is an unmistakable and often fear-provoking sound. But not for Pennsylvania Fish and Boat Commission (PFBC) biologists.
Subcaudal scales are large, flat scales located on the underside of a Timber Rattlesnake between the vent (anal scale) and the base of the tail rattle. If a snake has 21 or more subcaudal scales, it’s a male. Females have shorter, stubbier (PIC) tails with fewer subcaudal scales.
One of the first things we do is see if he already has a tag in him. He’s never been tagged or caught by us, so we’re going to prepare a PIT tag.
- Chris Urban said while scanning a captured snake with a Passive Integrated Transponder (PIT) tag reader.
PIT tags are 12-millimeter transponders that use barcode technology.
It gets implanted in the snake. It’ll stay in for the rest of the life of the animal. That’s that snake’s unique identifier for the rest of its life. It’ll attach itself to the wall of the snake and heal up pretty quick. They’re a great tool."
- Chris Urban
Once the assessment is finished and the snake is tagged, the biologists return it to where they found it. Then they’re on the hunt to find more snakes until they’ve cleared the monitoring site. Not all snakes are captured, but it’s common for biologists to find, catch and assess more than 20 snakes at one site during a spring survey.
As the agency with jurisdiction over reptiles and amphibians in Pennsylvania, the PFBC sets regulations to manage native species. Timber Rattlesnakes have a short hunting season that runs from June 10 to July 31 each year. Hunters need a fishing license and venomous snake permit and are allowed to keep one snake per year, given it’s at least 42 inches in length and has 21 or more subcaudal scales.
The Timber Rattlesnake is one of three venomous snakes native to Pennsylvania, along with the Eastern Copperhead and Eastern Massasauga. All three are considered Species of Greatest Conservation Need, a designation assigned to vulnerable animals the Commonwealth has a responsibility to protect.
[Timber Rattlesnakes] were a candidate to potentially be listed as threatened or endangered for a long time. We did an analysis and found that their numbers are pretty good, so we took them off our candidate list.
- Chris Urban
It’s probably our most managed non-game species we have. Timber Rattlesnakes are part of Pennsylvania’s natural heritage, so we’re trying to keep them here. We’re trying to monitor them through management to keep them here long-term, well beyond our lifetimes. That’s the goal: keep them part of Pennsylvania’s natural heritage.
- Chris Urban
Your Fishing License Dollars at Work
Funds from fishing license sales help the Pennsylvania Fish and Boat Commission protect and improve water quality and protect and manage reptiles, amphibians and other aquatic life like mussels. The agency works to ensure aquatic resources remain protected and water quality supports aquatic life; tracks endangered, threatened and rare animals under the PFBC’s jurisdiction; and manages species restoration efforts and habitat protections and improvement.