It has probably happened to you.  While driving Idaho’s roadways, you have accidentally hit a deer or other wildlife with your vehicle; or perhaps, you have witnessed such a collision.  Certainly you have seen the carcasses of animals lying alongside the shoulder of the road — motionless reminders that people and wildlife sometimes don’t mix.

     With roads and highways running through winter ranges and other valuable habitats and interfering with migratory routes, conflicts with wildlife on the roadways seem to be inevitable.  People can’t stop driving, and wildlife can’t stop moving.  So what can be done?

    Prior to the installation of the deer fence on I-15 south of Pocatello, the Blackrock section of the interstate had been a wildlife-vehicle collision issue for many years.  Over 3,000 vehicles pass through this corridor weekly.  Approximately 1,500 to 2,000 mule deer winter within a few miles of this stretch of interstate.  This had resulted in a recorded 102 mule deer vehicle collisions from 2009-2011, averaging over 30 deer killed per year.  The deer fence has helped reduce this number significantly despite the fact deer still find themselves on the wrong side occasionally.

    On Highway 30 alone — particularly the sections near Fish Creek Summit outside of Lava Hot Springs as well as the sections that run through Georgetown and Montpelier — deer and elk are hit and killed every year by motorists.  Data collected by the Fish and Game shows that since 2000, the average number of deer killed along just Highway 30 each year is 121. The average number of elk is 23.

    Both sets of wildlife mortality numbers from I-15 and Highway 30 are likely much higher since it is estimated that reported road kills make up about 50 percent of the total animals killed by collisions with vehicles.  That’s because after a collision some deer wander off and succumb to their injuries later.  

    Here is something else to consider.  According to Dr. John Bissonette, professor at Utah State University and unit leader with the USGS Utah Cooperative Fish and Wildlife Research Unit, 61.8 percent of the mule deer roadkill collected from Highway 30 by Fish and Game are female.  (Keep in mind that the gender of each animal is not always known due to the varying conditions of the carcasses.  Of those that aren’t identified, it is assumed that at least half of them are female.)

    Using the average of 121 mule deer killed per year on Highway 30, and the fact that the number of deer killed in vehicle collisions is undercounted by 50 percent, and assuming that those that are killed are mostly female (61.8 percent), then based on a reproduction rate of 1.2 fawns per doe, deer-vehicle collisions on Highway 30 alone equate a loss of nearly 538 fawns per year!  Again, these numbers are based on just the roadkill picked up by Fish and Game.

    Bissonette puts it simply, “You cannot trust what you actually see.  Because females are killed on the road, their offspring over several years are lost, further increasing the impact of roadkill.”

    Though these numbers are inexact, they still give you an idea of the magnitude of the potential problem.

    Of course, threats to human safety and damage to vehicles is also an important part of the issue .  Just a simple inquiry on an internet search engine yield hundreds of pictures of vehicles involved in wildlife collisions.  Images of broken windshields, dented hoods and smashed car doors with animals laying inside the vehicle — final resting spots — is enough to make anyone cringe and think hard about the dangers of sharing travel routes with wildlife.

    So, here are a few things to consider as you travel over the rivers and through the woods during this holiday season and winter months.

    1.      Wildlife, especially migratory species, are on the move, too.  Deer and elk are moving to lower elevations, often crossing roads in the process.  As you travel, keep your eyes open for wildlife along roadways, especially during early morning and early evening hours.

    2.      Drive slower in areas you know are frequented by deer.  This is especially true in urban/wildland interfaces such as Mink Creek, Gibson Jack, Johnny Creek and Buckskin.  Many “resident” deer forego long migrations and use these urban areas during the winter months.  Actually, deer can be found in these areas year round.  So besides looking out for bicyclists, joggers, kids and cars in these areas, keep an eye out for deer.

    3.      If you live in an urban interface with wildlife, please refrain from feeding deer and other critters.  You may inadvertently draw animals across a roadway or congregate them at a site that is dangerous for both motorists and the wildlife.

    4.      Pay attention to deer crossing signs or electronic signs warning of deer or elk on the roadways.  Counties and the Idaho Transportation Department put these up for a reason.

    5.      When you see one deer, there are likely others.  So, don’t assume that when one or two deer cross the road, you are in the clear.  There may be some animals lagging behind.

    6.      Certain species of raptors like hawks, owls and eagles have been known to collide with vehicles.  Hawks and owls will pursue their prey, even if it crosses a roadway, and they can collide with motorists.  Eagles, vultures, and other scavengers will feed on roadkill in the path of traffic.  Please do not assume these animals can quickly move or fly away.  Often, they become engorged with food, making it difficult to flee oncoming traffic.  Slow down to allow them a chance to move.

    7.      Give wildlife a “brake” — for their safety and yours!

    For more information about wildlife road mortalities in Idaho, actions being taken to help reduce collisions, and other information related to the issues of wildlife/vehicle collisions, visit Fish and Game’s website at http://fishandgame.idaho.gov/public/wildlife/?getPage=205.

Jennifer Jackson is the Regional Conservation Educator for the Idaho Department of Fish and Game’s Southeast Region.