Description
Until recently this species and the Pygmy Short-horned
Lizard were considered to be different subspecies of the
Short-horned Lizard. Recently it has been discovered that the two
groups are separate species. The Short-horned Lizard is gray,
yellowish, or reddish-brown. Males average 50 mm in body length
and females 70 mm.
Confusing Species
A small lizard with a fringe of tiny horns around its
sides, the Short-horned Lizard is not easily confused with any
other species in Alberta or Saskatchewan.
Distribution
The Short-horned Lizard is only found in southeastern
Alberta and southwestern Saskatchewan. It is also found across
much of the American southwest and part of Mexico.
Habitat
This lizard is associated with the mixed grass
prairie. It is frequently found at the edge of habitat types,
particularly coulee and canyon rims. South-facing slopes are
favoured, likely to extend the short active season.
Reproduction
Unlike most lizards, the Short-horned Lizard gives
birth to its young, rather than laying eggs. Because of this,
the mother can provide greater control over the temperature of
the embryos. This likely allows this lizard to exist so far
north. A female can give birth to up 13 young, each less than 25
mm long (about the size of a quarter) and weighing less than a
gram.
Natural history
The Short-horned Lizard eats mainly ants and other
insects. Females are considerably larger than males, likely to
allow room for their developing young. Males likely reach
maturity after their first hibernation. Females likely require
another year. Females can live for five years, or perhaps even
longer.
Conservation Concerns
Habitat destruction and conflicting land-use are the
main threats to the Short-horned Lizard. Grazing by cattle close
to canyon rims appears to eliminate this lizard. Development by
the oil and gas industry may be the greatest threat because of the
changes made to the landscape. Because Short-horned Lizards are at
their northern limit, their habitat requirements are exacting and
they are patchily distributed. Destruction of a key area may cause
the eliminatin of an entire population. This species is considered
Vulnerable in Canada.
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