Santa Catalina Island Rattlesnake
Crotalus catalinensis
A critically endangered island endemic notable for lacking a functional rattle segment, making it unusually silent among rattlesnakes.
- Venomous?
- Venomous
- Adult length
- 0.5-0.8 m (1.6-2.6 ft)
- Range
- Santa Catalina Island, Gulf of California, Mexico
Found a snake like this?
Identify any snake from a photo, free.
Overview
The Santa Catalina Island Rattlesnake is found only on Isla Santa Catalina in the Gulf of California, off the coast of Baja California Sur, Mexico. It is famous among herpetologists for its unusual, largely non-functional rattle.
Due to its extremely restricted range and threats from introduced predators, it is considered critically endangered and is a focus of conservation concern.
How to identify it
- Slender body with grayish or tan background color
- Dark, diamond or blotch-shaped dorsal markings
- Rattle segments fail to interlock properly, so the tail typically makes little to no sound when vibrated
- Broad triangular head, elliptical pupils, heat-sensing pits
- Distinguished from mainland rattlesnakes by its non-rattling tail and restricted island range
Habitat & range
Endemic to the rocky, arid terrain of Isla Santa Catalina, a small island in the Gulf of California. Inhabits desert scrub, rocky slopes, and cactus-dominated habitat found on the island.
Behavior, diet & reproduction
Thought to be more arboreal than many rattlesnakes, sometimes climbing into shrubs and cacti while foraging. Feeds primarily on lizards and birds, given the absence of native rodents on the island. Reproduces via live birth. Its silent rattle may be an adaptation to avoid alerting prey.
Frequently asked questions
Why doesn't this rattlesnake rattle?
Its rattle segments do not interlock properly, so shaking the tail typically produces little to no sound, an adaptation unique to this island species.
Where is it found?
Only on Isla Santa Catalina, a small island in the Gulf of California off Baja California Sur, Mexico.
Is it endangered?
Yes, it is considered critically endangered due to its extremely limited range and threats from introduced predators.
What does it eat?
Mainly lizards and birds, since the island lacks native rodent populations.
Santa Catalina Island Rattlesnake guides
In-depth guides for identifying and understanding Santa Catalina Island Rattlesnake.
