Wildlife Crossings: 11 Things (2024) You Have to Know

Highways have revolutionized our transportation abilities, but they also create a big problem for animals – which is where wildlife crossings come in.

Each year millions of animals are struck by cars while attempting to cross highways that cut through their natural habitats.

Collisions with large species like elk and mule deer can be fatal for the animals and passengers of the vehicle.

Obviously, highways aren’t going anywhere anytime soon. So, what can we do about it?

States across the nation have started creating wildlife crossings to allow animals to safely pass over dangerous highways.

Although the concept has been around for decades, states are still working on turning the idea into reality, so let’s take a dive into everything you could ever need to know about wildlife crossings.

If you live in an area with a lot of wildlife, this article may just inspire you to bring the concept up to your local city council.

1. What Are Wildlife Crossings?

Wildlife crossings refer to underpasses and bridges covered with natural vegetation that pass over–or under–highways (they may also be referred to as wildlife bridges or wildlife overpasses).

Their purpose is to allow wildlife to safely cross highways without risking their lives or the lives of those in vehicles.

But how do they work?

Well, the crossings are built in areas that animals are likely to cross.

Fences are also implemented to help direct animals to safe overpasses and underpasses.

The idea for wildlife crossings was first thought of during the 1950s in France, but the concept really caught on in the Netherlands–the country built over 600 wildlife crossings to protect local mammals.

In fact, the Netherlands is home to the longest crossing, measuring a half-mile long.

Many other countries, such as Canada and Australia, have implemented wildlife crossings, but the United States has been slow to adopt the concept.

So, why should the United States give wildlife crossings more consideration?

2. Why Are Wildlife Crossings Important?

Highways are big disruptors.

Not only are they responsible for killing countless animals, but they shrink the roaming areas of various wildlife.

When animals can’t roam in their natural habitats, it reduces the number of mating opportunities and negatively impacts the entire ecosystem.

In certain cases, highways may actually lead to the extinction of some species.

Of course, the other major importance of wildlife crossings is preventing animal collisions.

While driving along the road in the wilderness, drivers only have milliseconds to respond to creatures running into the middle of the road.

As the number of highways has increased, the rate of animal collisions has gone through the roof.

So, let’s take a closer look at car accidents caused by animals and some of the shocking numbers associated with them.

3. How Many Car Accidents Are Caused by Animals?

If animal collisions don’t seem like a big issue to you, they will after hearing just how prevalent and dangerous they are.

In the United States, there are between one and two million animal collisions each year.

That means there are anywhere from 2,700 to 5,400 animal collisions each day.

These collisions are more likely to kill animals, affecting wildlife populations, but they also injure and kill hundreds of drivers and passengers each year as well.

The medical and vehicle repair costs related to animal collisions total over $8 billion per year.

Does the issue seem a bit more important now?

Implementing wildlife crossings would save the country an incredible amount of money and do wonders for the health of wildlife populations.

The good news is that more and more states are looking to build bridges and underpasses to cut back the rates of animal collisions, but the projects require millions of dollars and take several years to be completed.

However, when wildlife crossings are put into place, they show excellent results, which is especially great for the animal that is responsible for a majority of the collisions.

Can you guess which animal it is?

4. What Animal Causes the Most Car Accidents?

The animals that cause the most car accidents are deer.

According to State Farm, deer were responsible for more than 1.3 million animal collisions in just one year.

But why are deer involved in so many of these incidents?

Well, a big part of the reason is that there are more than 35 million deer in the United States.

They are also known to travel between two and twenty miles per day, depending on the environment, which makes road crossings highly likely in areas with large deer populations.

Another reason deer cause so many car accidents is their size.

If a driver were to strike a small rodent, like a squirrel or rabbit, chances are the person wouldn’t even notice.

But deer, on the other hand, are big enough to do serious damage.

The average adult deer can weigh anywhere between 80 and 160 pounds and stand around 3 feet tall  (males tend to be bigger than females).

Those dimensions are more than enough to cause an accident that could turn fatal.

Other common species involved in animal collisions are rodents, raccoons, and dogs.

5. What is the Wildlife Crossings Pilot Program?

As the rates of animal collisions continued to climb in the 21st century, the United States finally addressed the issues in 2021.

The US Congress passed the Wildlife Crossings Pilot Program, which is backed by the Infrastructure Investment and Jobs Act.

Over a five-year period, the program will provide $350 million in grants to build new wildlife crossings to reduce the number of animal collisions and improve wildlife habitat connectivity.

Around 60% of the money will go towards projects in rural areas, where animal collisions are more common than in metropolitan areas.

In addition to projects to reduce wildlife collisions, the program also aims to support education and outreach efforts, research and monitoring, and economic development.

Committing $350 million is a great step forward, but will wildlife crossings actually reduce the number of animal collisions.

Well, why don’t we look at the numbers to find out?

6. Do Wildlife Crossings Actually Work?

The concept sounds great in theory.

But does a bridge covered in natural vegetation designed for animals actually work?

Oh yeah, they work, and they work shockingly well!

The Banff National Park in Canada is one of the best examples of how successful wildlife crossings can be.

Since the national park implemented overpasses and underpasses for wildlife, there has been an 80 to 90 percent decrease in animal collisions (before the crossings, there were about 100 incidents, now, there are typically less than half a dozen).

The park’s efforts have restored genetic connectivity across the highway, saved countless lives of animals and humans, and prevented costly vehicle damage.

So, I think it’s fair to say that wildlife crossings do, in fact, work.

When the new routes are introduced to the area, it typically takes a little while–sometimes years–for animals to begin crossing.

However, Banff National Park in Alberta has seen deer, black bears, mountain lions, moose, wolves, and lynxes make crossings.

7. How Many Wildlife Crossings Are There in the US?

In the United States, it’s estimated that there are over 1,000 dedicated wildlife crossings.

The crossings are specifically placed where animals are known to cross a certain stretch of highway.

But how do they know where these locations are?

Wildlife biologists use GPS collars to watch the movements of animals and track the most common routes.

They can also use this technology to see where the most collisions occur.

Once enough data is collected, states can make a strong assumption as to where the best sites for crossings would be.

A handful of states where animal collisions are a serious problem are making big financial commitments to improve animal and driver safety.

Those states include California, Colorado, Florida, New Mexico, and Wyoming (several other states have additionally issued executive orders to shift their attention toward wildlife crossings).

Since the US Congress passed the Wildlife Crossing Pilot Program, states and national parks have more support than ever to make hugely impactful changes; however, there is still a lot of work to be done.

8. What is the Wallis Annenberg Wildlife Crossing?

California is home to a lot of wildlife, including about 500,000 deer.

Well, the state also has the highest population of people, which is estimated at around 40 million.

In southern California, massive highways have been built to handle such a large population, but they have inadvertently blocked millions of animals from being able to cross from one side to the other.

All that is soon going to change now that the Wallis Annenberg Wildlife Crossing is underway.

What is that, you ask?

The Wallis Annenberg Wildlife Crossing will be the world’s largest animal crossing.

It will cross over the US-101, one of the biggest and busiest highways in the state, helping animals travel from the Santa Monica Mountains to the Simi Hills and Santa Susana Mountains.

Animals like deer, mountain lions, foxes, bobcats, coyotes, and serval other species will finally not be blocked by the US-101 for the first time in decades.

Construction on the crossing began in the summer of 2022, and it’s expected to be completed in 2025.

The US-101 is a ten-lane highway, requiring the crossing to be around 210 feet long and 175 feet wide–it will not include hiking trails, only game trails.

By the time of completion, the total price for the project will cost $100 million–saving the environment isn’t cheap, is it?

9. What is the Difference Between a Wildlife Corridor and a Wildlife Crossing?

The titles wildlife corridors and wildlife crossings are often used interchangeably, but there are actually differences between the two of them.

Wildlife corridors refer to the natural routes animals take that are based on learned behavior, inherited traits, and seasonal changes.

Often the migration corridors are the easiest paths that lead wildlife to food, water, or mates.

Routes could be as short as dozens of yards or as long as a hundred miles, such as the 125-mile route pronghorns in Wyoming take during the spring and fall.

Wildlife crossings, as we have been talking about, refer to overpasses and underpasses that allow animals to safely avoid highways.

Wildlife researchers take corridors into consideration to help them locate the best sites for crossings.

Corridors can also be manipulated through the use of fencing to channel animals to new crossings.

10. How Much Does It Cost to Build a Wildlife Crossing?

The cost of wildlife crossings greatly depends on the size and location.

For example, a small crossing over a remote road in Wyoming is going to be much cheaper than a crossing that goes over a multi-lane highway.

On average, wildlife crossings cost anywhere from $500,000 to $6 million.

It’s also important to note that underpasses are typically less expensive than overpasses.

That means the $350 million the Wildlife Crossing Pilot Program is bringing in could produce a significant number of new crossings.

However, that budget doesn’t leave much room for major projects like the Wallis Annenberg Wildlife Crossing, which costs $100 million.

Hopefully, as more structures are built and the data continues to show promising results, more funding will be allocated to the cause.

Fun fact: Leonardo DiCaprio donated a quarter of a million dollars to the California project–thanks, Leo.

11. What Are the Drawbacks of Wildlife Crossings?

When looking at the big picture of wildlife crossings, it seems like a foolproof plan, and in many ways, it is.

But there are a few important drawbacks to consider.

When you suddenly give flora and fauna access to another region, it could cause some serious disruptions, so let’s check everything that wildlife biologists need to be aware of.


Of course, the first major drawback to wildlife crossings is the cost.

One project could cost millions of dollars and only solve a sliver of the problem at large.

Unless the Federal Government or state governments assign more funding for these projects, it will take years and years for more major projects to begin.

bulletInvasive and Antagonist Species

Opening up a route for flora and fauna to cross highways helps restore gene connectivity, but it could also introduce invasive and antagonist species.

Certain insects have the ability to completely devastate an ecosystem.

Crossings could also introduce higher numbers of antagonistic species, like raccoons, that would decimate certain populations of animals.

bulletFire Risks

Wildfires are extremely hazardous.

Highways actually act as barriers that reduce the chance of flames spreading from one side to the other.

Wildlife crossings provide a clear path for fires to travel.

States like California need to be very cautious when choosing where crossings will be placed.

bulletExposure to Predators

Wildlife crossings could lead to an increase in predation.

If animals bottleneck just before and after the crossings, it will give predators a chance to make an easy kill.

As more of these crossings are built, wildlife researchers will have to monitor this possibility.

Final Thoughts

Highways and animals don’t mix–never have and never will.

Wildlife crossings could save countless lives of both animals and humans, prevent costly vehicle repairs, and restore the health of ecosystems.

Luckily, more attention and funding are being directed towards these efforts, and in the next decade, we will likely see several groundbreaking projects, such as the Wallis Annenberg Wildlife Crossing in California.

So, the next time you are driving through an area with a lot of wildlife, take note of how much roadkill you see.

Chances are that in areas with wildlife crossings, you might not see any at all.

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Erika Gokce Capital

Disclaimer: we are not lawyers, accountants or financial advisors and the information in this article is for informational purposes only. This article is based on our own research and experience and we do our best to keep it accurate and up-to-date, but it may contain errors. Please be sure to consult a legal or financial professional before making any investment decisions.


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