Pennsylvania is home for at least 21 species of snakes. Of those, only three species are venomous: the timber rattlesnake, the Northern copperhead and a very rare, small rattlesnake, the Eastern massasauga.

I have seen rattlesnakes and copperheads in the wild, and both in the Times News region. I’ll probably never see the massasauga because of its scarcity and the fact that it is only found in parts of five far western counties of Pennsylvania bordering Ohio.

All three of these snakes are venomous, and they are the only three snakes in Pennsylvania that have a pit.

Between the nostrils, found on the very front of a snake’s head and the eyes, is a noticeable opening called a pit. This pit is highly sensitive to changes in temperature. It allows a rattlesnake or copperhead to locate their prey, even in total darkness.

The pit vipers don’t actively pursue their prey, like a weasel or mink might, but they lay near a known travel corridor, usually among a rocky hillside area, waiting for a mouse, shrew or chipmunk to come close enough to them. After striking its prey, the small animal may travel a few yards before becoming helpless. Again, the pit helps direct the viper to the still-warm animal.

All snakes also have a very good sense of smell, but they do not use their nostrils for that sense. A snake often looks sinister when you see it stick out its rather long forked tongue. The tongue contains sensory structures that pick up microscopic chemical particles and deliver them to the Jacobson’s organ in the roof of the snake’s mouth.

That chamber is lined with special sensory cells that detect those compounds. The forked tongue gives it more surface area to collect these.

The tongue helps any snake to detect prey in the darkness, recognize human presence, and very importantly, to be able to detect pheromones needed to find mates. The snake constantly puts out the tongue and then dips the forked end into the Jacobson’s organ.

Timber rattlesnakes are generally found diagonally across Pennsylvania along the higher, rockier ridges that cross our state. None are in the southeastern counties.

Copperheads are found from mid-central Pennsylvania all the way into our southern counties. Copperheads prefer rocky hillsides, often closer to water.

Both species can be found best in spring when the temperature rises above 60 degrees and they seek rocks or open areas near cover to sit in the sun to warm them so they can have all body functions working properly. Both species’ young are born about now through late September.

Note: In rattlesnake habitat, I wear higher shoes, long pants and often long sleeves to keep my body heat in.

Last Week’s Trivia Answer: Bullfrog tadpoles need one year to complete metamorphosis.

Test Your Outdoor Knowledge: True/False questions below; answers in next week’s column.

1. Rattlesnakes can be aged by counting the number of their rattles.

2. A timber rattlesnake could reach 4 feet in length.

3. Copperheads and rattlesnakes both lay four to 15 eggs.

4. Pit viper young are not venomous the first four to six weeks of their lives.

5. A pit viper can lunge at a predator/threat at least 1 foot longer than their length.

6. A timber rattlesnake can live 30 years or longer.

7. A Northern copperhead is a close relative of the cottonmouth/water moccasin found in our Southern states.

8. A rattlesnake always rattles a warning before striking.

9. The two hollow fangs of pit vipers are replaced every three or four weeks.

10. A pit viper, with its well adapted heat-sensitive pits, can also smell and see extremely well.

11. The venom of a pit viper is a hemotoxin (affects the circulatory system) not a neurotoxin.

12. A snake’s tail is at least half the length of its body.

Email Barry Reed at breed71@gmail.com