Heterodon nasicus kennerlyi - Mexican Hog-nosed Snake

Description

The Western Hognose Snake is a light sandy brown in color, with darker brown or gray blotching, their coloration is not nearly as variable as the Eastern Hognose, Heterodon platirhinos, but they often have an ink-black and white or yellow checker patterned belly, sometimes accented with orange.

They are very stout for their size (a full grown 24-inch female is as bulky as a five-foot corn snake) and can grow from 15 to 33 inches in length, with females generally being larger than males. The characteristic of all hognose snakes is their upturned snout, which aids in digging in the soil. Hognose Snakes are considered to be rear-fanged colubrids, and do not pose any danger to humans and will generally only bite as a feeding response, rarely in defense. The defensive bite response is usually due to the temporary blindness experienced while shedding. Because the snake cannot see while shedding, it becomes skittish and more prone to bite in defense. A defensive bite may also occur in gravid (egg carrying) females. Commonly misnamed as venomous, they contain no venom or venom glads[citation needed] . The saliva they excrete is considered toxic to prey (frogs and toads) but not dangerous to humans. There has been some debate whether or not hognose are venomous, but there is no evidence to support that. Their saliva has some toxicity to smaller prey items, such as toads and frogs. The fangs have been referred to as just "enlarged teeth", but they are genuine fangs that are used for prey restraint. Despite the common belief, there is no evidence to support the fangs being used for "toad popping". Under this belief, the toads inflate their lungs to make swallowing difficult, but the fangs would penetrate the lungs and deflate them. However, whole toads with intact lungs are commonly regurgitated by recently captured wild hognoses.

Common names

blow snake, bluffer, (western) hog-nosed snake, faux viper, prairie hog-nosed snake, puff(ing) adder, spoonbill snake, spreadhead snake, Texas hog-nosed snake, Texas rooter, western hog-nosed snake, plains hognose snake.

Geographic range

Found from southeastern Alberta and southwestern Manitoba in Canada, south to southeastern Arizona and Texas in the United States and into northern Mexico. Disjunct populations in Minnesota, Iowa, Illinois, Missouri, Montana, and Arkansas.

Conservation status

This species is classified as Least Concern (LC) on the IUCN Red List of Threatened Species (v3.1, 2001). Species are listed as such due to their wide distribution, presumed large population, or because it is unlikely to be declining fast enough to qualify for listing in a more threatened category. The population trend is stable. Year assessed: 2007.

However, it is listed as endangered in the state of Iowa, and threatened in Illinois and South Dakota. It is more common in the southern end of its range, where holds no particular conservation status.

Behavior

The Western Hognose Snake is primarily diurnal, and makes use of a variety of habitats, including shortgrass prairies, grasslands, and rocky, semi-arid regions. It is typically a docile snake (though known to be highly aggressive in some individuals). If threatened (or perceives a threat), may flatten their necks (much like a cobra), hiss and make mock strikes if harassed, occasionally they even play dead if stressed enough. They feed on amphibians, lizards, and rodents. They breed in the spring, laying 4 to 23 eggs in the mid summer, which take approximately 60 days to hatch.

Reproduction

Western Hognose Snakes have been observed in copulation as early as February and March. They are oviparous, with females laying 4-23 elongate, thin-shelled eggs in June–August. Hatchlings are 5–9 cm in length and reach sexual maturity after approximately two years (this is predominantly based on size, not so much age).

Captivity

This species is more commonly kept and bred in captivity than any other member of its genus. It is small and hardy with a docile nature. Commercially available rodents are readily consumed and not much space or specialized care is required. It is also bred commercially with many color variations available.