As expected, the more open culverts and bridges have higher rates of successful passage. Culverts and bridges not built for wildlife and without wildlife fencing have lower success rates. Fencing is important to guide wildlife to the crossings. Future culverts would best pass mule deer if their lengths were less than 120 feet. Additionally, the width seems more important than height. Wider and shorter culverts work best at passing mule deer.
Wildlife managers and transportation engineers must work together to understand how wildlife-vehicle collisions impact mule deer populations. West Texas has hundreds of mule deer killed each year crossing highways. In most cases they cross in the same place year after year. Funds from the Mule Deer Foundation can be used to identify the high traffic crossings and build culverts or overpasses and 8 foot fences. You can help by joining the Mule Deer Foundation.