Why did the chicken cross the road? To get to the other side! Many may remember this as a childhood joke. However, the need for animals to get to the other side over busy roadways has caused many collisions and damage to both animals and humans.
Have you ever heard of an “animal bridge”? An animal bridge is a path dedicated to animals created above or below a highway, located in areas where a wildlife habitat is divided by highways. The goal of these bridges is to prevent wildlife – related accidents on the highway and fragmentation of the habitats which surround the highway areas. Not surprisingly, animal bridges are being built around the world to protect the ecosystem. The relationship between the highways we use when traveling and wildlife has always been a complex one. If you are interested in traveling, nature and wildlife, this is information you should be aware of.
Usually, when wild animals need to cross to the other side of a highway, they have no choice but to cross the busy road. Having to cross heavily trafficked roadways is a danger to the animals. One could even go so far as to call it a death trap. Imagine if, one day it was suddenly impossible to go easily to the area where one formerly lived.
For example, along a single stretch of highway in Utah, USA, 98 deer, three moose, two elk, multiple raccoons, and cougars were struck in car collisions in the time of just two years.
A total of 106 animals died. The United States is home to 21 endangered species, including key deer in Florida, bighorn sheep in California, and red-eared turtles in Alabama. All of which are threatened by road deaths. Over the last 15 years, reported wildlife-auto collisions have increased by 50%, with an overall total of 1 – 2 million large animals killed each year by auto collisions.
One way to create awareness is to post an “animal crossing” sign for the driver to be aware. However, signage is more something that lowers the risk to drivers than lowering the risk to wildlife.
In addition, many traffic collisions with animals are a big problem for humans. According to the US Highway Traffic Safety Administration, it is estimated that more than one million car accidents in the United States cause approximately 200 deaths each year, resulting in over $8 billion in damages regarding repairs and injuries. At the least, collisions are financially expensive. The cost of a deer-auto collision averages $8,190, an elk-auto collision costs about $25,319, and an moose-auto collision costs $44,546, including personal injury and death, towing, and vehicle repair costs. Due to all of this, a solution called “animal bridge” was born.
When a bridge or underpass for wild animals is constructed, they recognize it as a safe passage and begin to use it. This is how animal bridges help wild animals to safely cross the road.
What is an animal bridge
Animal bridges, also known as ecoducts or wildlife intersections, are structures which provide a way for animals to safely cross man-made barriers such as highways. Crossings for wildlife include viaducts, underpass tunnels, amphibian tunnels, and ladders for fish.
For the most part, animal bridges are unobtrusive. They can be often designed in a natural shape so that animals can use the bridge without stress. One may have passed under a bridge for animals without even realising it.
Is there really such a thing as an animal bridge? Some may be surprised to hear about animal bridges, especially if it is not a common sight, but this is not a new phenomenon.
Historic animal bridges
In the 1950s, the world’s first animal bridge was built in France in order to help hunters to guide the deer. Since then, many animal bridges have been built in Europe.
Canada and the United States have been building animal bridges for about 30 years.
Thousands of wildlife bridges have been built in the United States over the past 30 years, including underpass tunnels, bridges, and overpasses. Many animals make use of these animal bridges with examples such as mountain goats in Montana, speckled salamanders in Massachusetts and bighorn sheep in Colorado. These wildlife paths are also used to further protect endangered species such as turtles and the Florida Panther.
The animal bridges that started in Europe are now spreading all over the world.
The role of the animal bridge
Animal bridges help to avoid collisions between automobiles and wildlife. As mentioned above, not only can these bridges work to prevent wildlife being killed or injured, but can also work to avoid human and property damage as well.
In addition, by supporting the crossing of wildlife, the bridges protect their habitats, aids in maintaining habitat connections, and prevents further habitat fragmentation. Not only that, animal bridges are important in terms of promoting breeding practices that can be hindered by highways. Wildlife mating is an important aspect for species survival. The inability to move between areas can result in a local reduction of numbers if the population cannot find each other.
In Canada’s Banff National Park, a combination of fences and animal bridges has reportedly shown an 80% reduction in traffic accidents. There is also data that the number of traffic accidents has dropped by 90% after the state of Arizona in the United States installed an animal bridge in Flagstaff specifically built for Elk and more than 12 additional underpasses and overpasses.
Although it can be costly, it seems preferable to install as many animal bridges as possible.
Unique animal bridges around the world
Animal bridges are now showing up all over the world. Such bridges are used by various animals in various areas.
The Nutty Narrows Squirrel Bridge in Washington, USA, for example, is made of rope that allows squirrels to easily cross the road. In Oregon and Washington, the underdrain constructed under the road that crosses the water has been expanded and is being used as a fish crossing.
In the 1980s, salamanders in Massachusetts were among the first animals to benefit from the “animal bridge” in urban America. Every spring, locals formed a “bucket brigade” that would carry salamanders from a forest hideaway on one side of Henry Street to a breeding pond on the other. By 1987, conservationists and public works officials had begun to build official underpasses for the cause, and now 100-200 salamanders (and small frogs) pass through the tunnel each year.
In 2016, an underpass was built under Highway 160 between Durango and Bayfield, Colorado. According to remote photo images, the corridor is used daily by deer, coyotes, raccoons and other small animals.
Australia has a particularly unique animal bridge. The animal bridge on Christmas Island is much smaller than the regular overpass, and it is used by 50 million red crabs to migrate each year on their migration route.
Brisbane also has three canopy bridges which are woven with heavy rope on top of the notoriously dangerous Compton Road, allowing for both gliders and opossums to swing in the sky.
There are 66 elevated bridges and eco-ducts in the Netherlands, including the Natuurbrug Zanderij Crailoo which passes through railroad, river, business park, sports complex and golf course, which is the longest animal bridge in the world, at about 800 meters long. It primarily protects badger, boar, and native deer populations.
In Oslo, Norway, there is a “bee highway”. To protect the population of endangered bees, locals have begun planting flowers along rooftops and parks along designated routes, and bees can now happily move around town.
There are animal bridges in Japan also.
Turtles have caused mass accidents in Japan. A turtle will follow the light and eventually get lost. Between 2002 and 2014, there were incidents in which a turtle crossing the railroad caused a mess of 13 trains in Kyoto and Nara. To save those turtles and prevent accidents, engineers at the West Japan Railway Company and the Suma Sea Aquarium have created a special U-shaped turtle path under the existing tracks. Turtles are now able to cross the tracks without getting stuck or crushed when the train arrives.
In Africa, elephant walkways are being built to allow for large animals such as elephants to reunite with members of a fragmented herd.
The most notable example of a successful animal bridge is Banff National Park in Alberta, Canada. Since the first animal bridge was constructed in 1996, 38 underpasses and 6 animal bridges have been installed by 2014, recording more than 150,000 large mammal crossings. Banff National Park has more animal bridges than any other park in the world, helping eleven species of large animals, including wolves, coyotes, cougars, elks, deer, bighorn sheep, and more recently the Wolverine and Lynx (among others).
The creation of the animal bridge helps with the coexistence of humans and animals.
On your next road trip, be aware that to look up above the roads in forested areas.
You may be able to find the “animal bridge” in use by wild animals.
Would you like to know more about eco-friendly travel?
Please click here to sign up for the Ecotourism World newsletter, and receive inspiration directly to your email inbox.