Roads act as ecological traps for snakes. As ectotherms, they are drawn to the warmth of highways, which increases the risk of vehicle collisions. Some species freeze when faced with traffic, further raising mortality. Poorly fenced construction sites add to the danger, as snakes may become trapped in trenches, pipework, or machinery.

Wandering species are particularly vulnerable. Studies show gopher snakes experience higher road-kill rates than rattlesnakes, especially during breeding migrations in spring and summer, and juvenile dispersal in fall. Construction sites also pose hazards, often attracting females to nest.

Planning engineers have a responsibility to reduce these impacts. Properly designed exclusion fencing, used with features such as eco-passages, can greatly reduce mortality on roads and construction sites. Fencing is also valuable for population assessment before development begins..