Yellow Bellied Racer

Coluber constrictor

Species at Risk: Sensitive


Yellow-bellied Racers are extremely rare in Alberta. For many years, there was great debate as to whether they were even a native species. As the name would suggest, this is a slender, fast-moving snake with smooth scales. Adults are plain-colored above (grey, brown, olive or slightly blueish) with white to yellow bellies, while the young are pale tan to cream with brown blotches. Adult racers range from 50 cm – 1.5 m in length. They are active, diurnal hunters, with large eyes and excellent vision. In spite of the “constrictor” in their scientific name, they do not constrict their prey to kill it, but instead depend on the strength of their jaws to crush it. Young racers primarily eat invertebrates (grasshoppers, crickets, caterpillars), while adult racers prefer vertebrate prey, like rodents, frogs, and small reptiles. Uniquely, they tend to hunt with their head held up to give them a better view of potential prey items.

Female Yellow-bellied Racers reach sexual maturity at about 2 years of age, and males around 3 years of age. Clutch size is about 9 eggs.


Yellow-bellied racers primarily inhabit grasslands, which favor their hunting style.

There is a confirmed yellow-bellied racer den site in southern Alberta, which was discovered in 2014. Given the small numbers of Yellow-bellied Racers in the province, the exact location of the den site in Alberta is a closely guarded secret amongst biologists. We wish to respect this in order to protect them from illegal collection and excessive harassment by curious herpers

Given the very small population (<10 000), yellow-bellied racers are considered threatened in Alberta. They are vulnerable to decline from any sort of natural disaster that wipes out their den site (land slides, flooding, etc), as well as the usual pressures of road mortality, habitat loss and degradation, etc.


Peterson Field Guides: Western Reptiles and Amphibians (3rd ed) by Robert C Stebbins.

External link opens in new tab or windowCOSEWIC Species Database - Yellow-Bellied Racer
External link opens in new tab or windowWikipedia - Coluber Constrictor Flaviventris
External link opens in new tab or windowAlberta Wilderness - A Focus Done By Nigel Douglas

Photo by Kyle Welsh