Mountain Short-horned Lizard

Phrynosoma hernandesi

Species at Risk: At Risk

Alberta only has one lizard species, but it certainly is an interesting character. The short horned lizard is a small, stout animal with a short neck, legs and tail. This physique, gave it the nickname “horny-toad”, of which after closer inspection, it shares no resemblance to. Short horned lizards are covered in scales, most of them pointed, breaking up it’s outline amongst the rocky soil and making it a hard prey item to swallow. A small crown of horn-like scales borders the back of the head and along the sides, from armpit to groin, is a single row of fringe scales. Overall colouraton is a mottling of light sandy brown, with greys and darker brown patches. The belly is a uniform cream white. The short horned lizard has a snout to vent length of 4-7cm. Males are smaller than females, and also have a clear hemi-penile bulge and enlarged femoral pores. Eight to thirteen live young are born in late July or August and they eat a mix of invertebrates with a large portion being ants. When winter comes, they dig themselves a shallow retreat underground at the base of the coulee. Snow collects here and may be essential insulation to protect the lizard from extreme cold.

Dry coulees, south facing hills, sagebrush and juniper plants adjacent to short-grass prairie are the habitat you’ll find these lizards in. You might ask why our “Mountain” short horned lizard is confined to Alberta’s flat, and arid southeastern corner. This is because in our province this species is at the northern limit of it’s range. These lizards are very cold-weather adapted, and as such, further south where it is even hotter and drier, they inhabit the cooler high elevations, to about 3400m above sea level.

The mountain short horned lizard in Alberta has a limited range, with low population densities. It is a very cryptic animal and hard to find, but once stable populations may be declining or disappearing. Their very specific habitat preferences make them susceptible to habitat destruction. The oil and gas industry may have negative effects as they explore and uncover new reserves. Global warming is seeing less snow cover, which may affect their ability to hibernate without freezing.

The Amphibians and Reptiles of Alberta by Anthony P. Russell and Aaron M. Bauer