Massasauga |

Massasauga

Sistrurus catenatus catenatus; Eastern massasauga rattlesnakes can reach up to 30 inches in length. The snakes have irregular dark saddles alternating against a lighter background. Their tails end in the namesake “rattle,” a collection of modified scales. Eastern massasaugas rarely use their rattle, however, opting instead to stay motionless in response to intruders. The rattlesnake primarily feeds on small mammals, such as mice, shrews and voles. The species detects prey via vibrations in the ground, their strong sense of smell and heat-sensing pits on the side of the face. Using its fangs, the massasauga injects prey with venom before swallowing its meal whole. While massasauga venom is toxic, the species is generally not regarded as a threat to humans. The venom of rattlesnakes contains specialized digestive enzymes that disrupt blood flow and prevent blood clotting. Severe internal bleeding causes the death of the small animals that this snake eats. After envenomation, the rattlesnake is able to withdraw from the dangers of sharp toothed prey animals until they are subdued and even partially digested by the action of the venom.

Exposure: 1/15 sec; f/5.0; ISO 400; 70mm; Pentax K5 with Sigma 70mm f2.8 DG Macro.

Shooting these snakes at the Phoenix Zoo is always a challenge. For starters, the viewing area is an unlit tunnel, with the only light source being the lights in the animals’ enclosures. The glass is always dirty from hundreds of zoo visitors, and the snakes themselves, being well fed and with no threats from predators, rarely move. I tried setting the camera up on a tripod, but the distance between the lens and the glass really makes dirt and reflections on the glass stand out. I also forgot to bring my homemade pop up flash extender/diffuser, made from a Pringles can and tracing paper, so shutter speeds were very slow, and as the camera was handheld, actually getting any part of the little guy into focus was something of a minor miracle. I could have raised the ISO, but I really wanted to keep the noise levels as low as possible. Anyway, I love the coloration of this species, and even though they are supposedly one of the more shy types of snake, this one always seems to be out where I can at least see him.