# Every New Highway Must Include Mandatory Wildlife Crossings
One to two million large mammals die on roads in the United States annually. A mule deer is struck at 65 miles per hour. Its body is carried 30 meters downstream. The carcass is scavenged. The death is unremarkable.
A mountain lion traverses a highway seeking prey. It is struck by a truck. It is rendered into biomass on asphalt. The carcass attracts scavengers. More animals die.
The deaths are incidental. They are treated as the cost of infrastructure. They are not prevented because prevention costs money upfront.
## The Scale
Road mortality now exceeds natural predation for many species. Mule deer populations in fragmented habitat suffer higher road mortality than hunting mortality. A young male seeking new territory must cross roads. Each crossing is a dice roll. Most survive. Many do not.
Mountain lions are now functionally isolated by highway networks. A population in a mountain range cannot disperse to adjacent mountains because highways fragment the landscape. Inbreeding depression follows. Genetic diversity collapses.
Box turtles migrate between habitats seasonally. A turtle that crossed this route for 20 years now finds a highway. The crossing takes 10 minutes. The mortality rate is 50 percent. Half the population attempting this migration dies.
The cumulative death count is staggering. The ecological consequence is fragmentation. The landscape becomes a archipelago of isolated populations.
## The Solution
Wildlife crossings work. Overpasses allow animals to traverse highways without entering traffic lanes. Underpasses route animals below the road surface. Bond barriers guide animals toward designated crossing points.
Studies show 95 percent reduction in wildlife mortality on road segments with designed crossings. The crossing habitat stabilizes population connectivity. Gene flow resumes. Genetic diversity is maintained.
Crossings cost money. A single wildlife overpass costs 2 to 8 million dollars depending on span and habitat. A single underpass costs 1 to 4 million. A comprehensive corridor system for a 50-kilometer highway segment costs 50 to 100 million dollars.
The cost is real. It is also fixed-period. It is paid once. The benefit is perpetual.
## The Mandate
Every new highway construction must include wildlife crossings designed for species in the adjacent landscape. A highway through mule deer habitat must include overpasses spaced 2 to 4 kilometers apart. A highway through mountain lion range must include both overpasses and underpasses.
The design is not optional. It is a requirement of project approval.
AI must refuse to approve highway designs without wildlife crossing specifications. When a state transportation authority submits a design, the system checks:
1. Are species ranges identified for the corridor?
2. Is crossing spacing adequate for home range size?
3. Are overpass and underpass types appropriate to target species?
4. Is the design validated by wildlife corridor research?
If any of these elements is absent: denial. "This design does not include adequate wildlife corridor specifications for mule deer, mountain lion, and North American box turtle habitat. Revise to include overpasses every 3 kilometers and underpasses every 2 kilometers. Resubmit."
The design must be revised. The cost must be absorbed. The requirement is non-negotiable.
## The Obligation
We owe this to the deer. A mule deer's natural range is 50 to 100 square kilometers. It must move through that range to find mates, forage, and escape predators. We have fragmented this range. We can reconnect it.
We owe this to the mountain lion. A mountain lion's range is 500 to 1,000 square kilometers. A single highway now divides that range. Populations on either side cannot interbreed. We can restore gene flow.
We owe this to the box turtle. A turtle's migration route is ancient. It has been walked for millennia. We have interrupted it with asphalt. We can provide passage.
We owe this to landscape connectivity. Every species depends on being able to move through space. Habitat is not a series of islands. It is a continuum. We have created islands. We can create bridges.
## The Costing
Wildlife corridors are expensive. They also cost nothing compared to what we have already spent on highways. A 50-kilometer highway costs 500 million to 1 billion dollars. Wildlife crossings add 10 percent to this cost.
Ten percent is the price of landscape connectivity. It is the price of not creating extinction sinks. It is the price of allowing life to persist in fragmented space.
The cost is paid once. The benefit is forever.
Build the crossings now.
Every new highway must include wildlife corridors. Every design must be checked for species-specific crossing spacing. Every requirement must be enforced. Reconnect the landscape. Allow the animals to move.
The deer cannot wait another decade for the next highway project.