I never expect to see a snake. When I do, it’s momentarily alarming (yes, I still have a tad bit of residual herpetological fear) and then unexpectedly delightful. Recently, I spied a Smooth Green Snake (Opheodrys vernalis) hanging out in the grassy border of a local rail trail.
This small green to light brown snake with the creamy-colored underside is native to the Nearctic region ranging from Canada to
the highlands of central Mexico. They are best known for their group-living arrangements, called hibernacula. These are groups of 100 to 150 individual snakes cohabitating. Hibernacula have been found in Minnesota and Manitoba. They may exist elsewhere too but this isn’t well-documented. (Ok, I’m kind of creeped out again.)
In Maine, Smooth Green Snakes are a secure, or relatively abundant, species. They are found in the meadows, wetlands, marshes, bogs, farmlands, and the abandoned fields that comprise a fair amount of the state. With this kind of habitat adaptability, I would have thought that they were a prevalent and secure species everywhere. Wrong again.
Next door, in New Hampshire, they are listed as vulnerable. In the northwest corner of Indiana, the only place where they are found in the state, they are in decline. Similarly, they are considered imperiled in Ohio, Montana, and Wyoming. They are most likely gone from Missouri. Surprisingly, a quick check of the IUCN Red List reports that they are of least concern globally.
This is curious. Does local extirpation signal a declining ecosystem? Sometimes yes, but sometimes there are other reasons.
We know that extirpation results when the local environmental conditions can no longer the species. Some of it is driven by human activities but not all. Heat waves, glaciation, and even volcanic activity can result in such dramatic changes in the ecology.
While habitat loss and pesticides are often cited as the reason for the snake’s population decline, there may be other factors at play. Little research seems to be done on this species, as it neither threatens humanity nor offers great benefits other than eating some pests. Sadly, it may just disappear before we know much more about it. And we may never know why.
An excellent resource to learn more about species’ status – https://explorer.natureserve.org/Taxon/ELEMENT_GLOBAL.2.103123/Opheodrys_vernalis