Anniella pulchra

How can a critter that looks so much like a snake be a lizard? If you looked very closely at the California Legless Lizard (Anniella pulchra) you might see that unlike snakes, they have moveable eyelids.  Also unlike most snakes, many lizards, this one included, they have the ability to purposely detach their tails to trick predators. About the length and size of a pencil, this unusual lizard burrows easily through the sand while feasting on sowbugs, ants, insects and insect larvae. As far as we can tell, legless lizards breed once a year and have been observed giving birth to as many as three offspring while in captivity. Because they thrive in the very same dunes that we humans love to frequent, these small reptiles have seen their habitats greatly impacted and are currently designated a California Species of Special Concern. They are found only in California and northern Baja.

Microhabitat utilization and home range of the fossorial California legless lizard (Anniella pulchra) were studied in four hectares of sand dune in central California (Kuhnz et. al 2005). Methods were developed using Passive Integrated Transponders (PIT-tags) and underground biotelemetry to track movements within microhabitats, in response to disturbance, and to determine home range and dispersal ability (Kuhnz 2000a, Kuhnz 2000b).  This is the most abundant population of Anniella pulchra known (n = 3,582; 0.228/m^2).  Abundance was greater in quality habitat (e.g. near lupine bushes) and with greater soil moisture, but lower in disturbed soils. They were routinely found at temperatures below 20 degrees C, and were active day and night. The average home range was 71 m^2 (std. dev. = 87.2). In the laboratory, Anniella moved underground through a system of persistent burrows and vertically migrated to a depth of 46 cm. PIT-tags were a viable method for tracking legless lizards and could be used with other small fossorial animals.

This project continues today. In 2010, we found lizards that were pit-tagged and released 12 years ago. We look forward to seeing just how long these lizards, which were probably at least 4-5 years old when tagged, will live.