Western Hognose Snake {Heterodon nasiciis) 



Description: The Western Hognose Snake is a mid-sized, heavy-bodied snake reaching 32" The 

 dorsal ground color is yellowish- to grayish-brown, with 3 rows of darker brown to black 

 blotches running down the back The belly is dark gray to black, sometimes checkered. Its 

 nose has a keel on the top and is upturned. 



Eggs and Young. Clutches have 7-15 eggs which are white and elliptical, with thin, papery 

 shells; length averages 32.5 mm (26-38 mm) and width 18 mm (14-23 mm). Young are 139- 

 197 mm at hatching and are similar in color and pattern to aduhs (Piatt 1969). 



Similar Species: No other Montana snake has a keeled nose. Coloration is similar to both the 

 Gopher Snake, Western Rattlesnake and juvenile Racer. 



Habits and Habitat: The Western Hognose Snake is found on the plains of eastern Montana. It 

 seems to prefer arid areas, farmlands and floodplains, and particulariy areas of gravelly or 

 sandy, loose soil. The keeled or shovel-like nose is thought to help it to dig down to its food, 

 which it finds by smell. Apparently toads are its preferred food, though frogs, insects, and 

 other small animals are also eaten (Piatt 1969). It is active primarily during the daylight hours. 

 Little is known of reproduction in Montana. It is likely that a female will only breed every 

 other year in Montana. Road-killed adults were encountered on 25 and 28 June in 1998. 



The Hognose is famous for its behavior in the face of a threat. At first it will puff up its 

 neck, as does a cobra, and hiss and strike at its enemy. However, this is all a bluflf; very rarely 

 will it actually bite. If this threatening strategy does not work, it will pretend to die. It 

 appears to go into convulsions, writhing on the ground, sticking its mouth in the dirt, and 

 eventually rolling on its back and going into a trance that makes it appear to be dead. If 

 turned right-side-up, it will roll back over and continue its deception. If left alone for a few 

 minutes, it will right itself and continue on its way. The initial aggressive display and basic 

 rattlesnake-like coloration cause many to be killed needlessly by people who mistakenly 

 believe it to be venomous. 



Surveying: They may be surveyed for by slowly walking through appropriate habitat and 

 carefijUy watching for them, conducting surveys on warm, sunny days enhances sampling 

 success. However, as with many lizards and snakes, they may easily be missed. Carefijlly 

 documented incidental observations may provide the best clues to their distribution. They 

 may be also taken in pitfall or funnel traps with drift fences. Mark-recapture methods offer 

 the best opportunity for determining population status. 



Status: Western Hognose Snakes are widespread in eastern Montana, but apparently not very 

 abundant. There are relatively few reports of this species from Montana, even though they 

 have been documented in the state since the passage of Lewis and Clark in 1805 (Burroughs 

 1995). There are only 5 records in the MTNHP database from within the boundary of the 

 Miles City District, BLM since 1995. The species was encountered twice in 1998, from 

 Custer and Garfield counties (Appendix 4). Hognose snakes are collected for the pet trade, 

 and populations may be vulnerable to commercial collectors. Additionally, since toads are its 

 preferred food, any decline in toad populations would be expected to negatively impact 

 Western Hognose Snakes. Of particular interest would be documentation of any denning sites 

 located. All encounters with this species should be documented. 



Montana Natural Heritage Program rank: G5 S3?. Species of Special Concern. 



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