A North American grizzly bear (Ursus arctos horribilis)

The Pacific Northwest grizzly bear population has nearly tripled since 1975. How did this happen? We gave them better roads.

Conservation efforts like the Yellowstone to Yukon Conservation Initiative (Y2Y) are behind these roads. Y2Y’s mission is to connect habitats “so people and nature can thrive,” and it’s been a success.

Creating pathways for these bears seems obvious. If bears can’t meet up, how can they reproduce? If bears can’t range over wide areas, how can they find enough food?

While it is getting easier for humans to get around, it is getting harder for animals. Evidently, there is not so much wild land left. Humans occupy more land than any other animal – you can find us on 50-70% of the world’s landscapes.

Addressing our needs often means neglecting those of wildlife. Not only do people destroy habitats, but human infrastructure also keeps animals from moving between areas. This is habitat fragmentation. It decreases the number of animals an ecosystem can hold, isolates them, and decreases their genetic diversity.

These changes undermine ecosystem resilience. Animals like the panda, tiger, and gorilla are in danger of extinction due to habitat fragmentation. In fact, habitat fragmentation is the number one cause of species extinction since 1950, the beginning of the Anthropocene or “the recent age of man.”

Just as we build infrastructure that helps people from Point A to Point B, we need to build corridors helping wildlife do the same.

Wildlife corridors expand access to resources. For many species, a primary cause of extinction is that they can’t access the food, water, or shelter they need to survive. Corridors can provide a pathway to more resources.

Corridors also allow wildlife to migrate. Seasonal migration is a behavior common in many animals, and corridors allow them to fulfill their search for food, water, and mating partners. Wildlife corridors can also increase a population’s genetic diversity by allowing different populations to mate and reproduce.

A wildlife corridor can be small or large, terrestrial or aquatic. It can be an overpass or a tract of land connecting protected areas. It can even be the trees along the road and the flowers that you and your neighbors plant. This is part of their appeal.

In Montana, a purchase of a mere 80 acres will make a huge difference for grizzly bear populations, allowing them to move between two mountain ranges, breed with other populations, and quite importantly, avoid humans. Legislation like the Wildlife Corridors Conservation Act and standards set by the Intergovernmental Panel on Climate Change help to fund and popularize wildlife corridors as a solution to habitat fragmentation.

Wildlife not only needs habitat, they need access to it. It’s unlikely that we’ll stop needing buildings and roads anytime soon, so we need a compromise. Wildlife corridors won’t solve all the problems humans have created, but they will improve upon some. We’ve seen the damage climate change has already done to wildlife. Corridors and other innovative strategies will make a significant difference in the decades to come.