Roadkill is an animal or animals that have been struck and killed by motor vehicles. In the United States of America, removal and disposal of animals struck by motor vehicles is usually the responsibility of the state's state trooper association or department of transportation.
During the early 20th century, roadkill or "flat meats" (or "Highway Pizza") became a common sight in all industrialized First World nations, as they adopted the internal combustion engine and the automobile. Roadkill can be eaten, and there are several recipe books dedicated to roadkill. One of the earliest observers of roadkill was the naturalist Joseph Grinnell, who noted in 1920: "This [roadkill] is a relatively new source of fatality; and if one were to estimate the entire mileage of such roads in the state [California], the mortality must mount into the hundreds and perhaps thousands every 24 hours."
In Australia, specific actions taken to protect against the variety of animals that can damage vehicles – such as bullbars (usually known in Australia as 'roo bars', in reference to kangaroos) – indicate the Australian experience has some unique features with road kill. In North America, deer are the animal most likely to cause vehicle damage.
Distribution and abundance 
The number of animals killed in the US is estimated at a million per day.
About 350,000 to 27 million birds are estimated to be killed on European roads each year.
Species affected 
A recent study showed that insects, too, are prone to a very high risk of roadkill incidence. Research showed interesting patterns in insect/butterfly roadkills in relation to the vehicle density. Although the insect community is equally at risk, much of the attention goes to bigger, more charismatic animals.
Fauna mortality as result of roadkill can be very significant for species with small populations. Roadkill is estimated to be responsible for 50% of deaths of Florida panthers, and is the largest factor for European badger deaths in England. Roadkill is considered to significantly contribute to the population decline of many threatened species, including moose, wolf, koala and eastern quoll.
In 1993, 25 schools throughout New England, United States participated in a roadkill study involving 1,923 animal deaths. By category, the fatalities were: 81% mammals, 15% birds, 3% reptiles and amphibians, 1% indiscernible. Extrapolating these data nationwide, Merritt Clifton, editor of Animal People Newspaper estimated that the following animals are being killed by motor vehicles in the United States annually: 41 million squirrels, 26 million cats, 22 million rats, 19 million opossums, 15 million raccoons, 6 million dogs, 350,000 deer. This study may not have considered differences in observability among taxa (i.e. dead raccoons are easier to see than dead frogs), and has not been published in peer-reviewed scientific literature.
US State wildlife roadkill observation systems 
Recently (since 2009), statewide roadkill observation systems have sprung up, enrolling hundreds of observers in reporting roadkill on a website. The observers, who are usually naturalists or professional scientists, provide identification, location, and other information about the observations. The data are then displayed on a website for easy visualization and made available for studies of proximate causes of roadkill, actual wildlife distributions, wildlife movement, and other studies. Roadkill observation system websites are available for the US states of California, Maine, and Idaho. In each case, index roads are used to help quantify total impact of vehicle collisions on specific vertebrate taxa.
State wildlife roadkill identification guide 
The first wildlife roadkill identification guide produced by a state agency in North America was published by the British Columbia Ministry of Transportation (BCMoT) in Canada in 2008. BCMoT’s "Wildlife Roadkill Identification Guide" focused on the most common large carnivores and ungulates found in British Columbia. The guide was developed to assist BCMoT's maintenance contractors in identifying wildlife carcasses found on provincial highways as part of their responsibilities for BCMoT’s Wildlife Accident Reporting System (WARS).
Collisions with animals can have many negative consequences:
- Injury to, or death of, vehicle occupants
- Loss of valuable livestock or pets
- Harm to endangered species
- Death and suffering of animals struck by vehicles
- Vehicle damage
- Economic losses (cleanup, repairs to vehicles, etc.)
- Decrease in enjoyment of a tourist holiday due to frequent roadkill encounters.
Large animals 
Collisions with large animals with antlers (e.g., deer) are particularly dangerous, as the head has a tendency to separate and come through the windshield, but any large, long-legged animal (e.g. horses, larger cattle, camels) can pose a similar cabin incursion hazard. Injury to humans due to driver failure to maintain control of a vehicle either while avoiding, or during and immediately after an animal impact, is also common.
Small animals 
In regions where squirrels, rabbits, birds, or other small animals are plentiful, a tire-flattened one is a common sight on roadways. Motorists have caused serious accidents by trying to swerve or stop to avoid a squirrel in the road. Such evasive maneuvers are pointless, since small rodents and birds are much more agile and have much quicker reaction times than motorists in heavy vehicles. There is very little a driver can do to avoid an unpredictably darting squirrel or rabbit, or even to intentionally hit one. A humane and prudent course of action is to continue driving in a predictable, safe manner, and let the small animal decide on the spur of the moment which way to run or fly; the majority of vehicular encounters end with no harm to either party.
On the other hand, slow-moving reptiles such as turtles and snakes are easily steered around, if speed and traffic conditions permit such evasive maneuvers. Medium-sized slow-moving mammals such as opossum, beaver, or skunk should be avoided if possible.
Night driving 
Although strikes can happen at any time of day, deer tend to move at dawn and dusk, and are particularly active during the October–December mating season. Driving at night presents its own challenges: nocturnal species are on the move, and visibility, particularly side visibility, is reduced. When headlights approach a nocturnal animal, this makes it hard for the creature to see the approaching car (nocturnal animals see better in low than in bright light). Furthermore, the glare of vehicle headlights can dazzle some species, such as rabbits; they will freeze in the road rather than flee. The simple tactics of reducing speed and scanning both sides of the road for foraging deer can improve driver safety at night. Drivers may see the glow of a deer's eyes before seeing the animal itself.
Wildlife crossings 
Wildlife crossings allow animals to travel over or underneath roads. They are most widely used in Europe, but have also been installed in a few US locations and in parts of Western Canada. As new highways cause habitats to become increasingly fragmented, these crossings could play a crucial role in protecting endangered species.
In the American West, roads may pass through large areas designated as "open range", meaning no fences separate drivers from large animals such as cattle or bison. A driver may round a bend to find a small herd standing in the road. Open range areas are generally marked with signage and protected by a cattle guard.
In an attempt to mitigate $1.2 billion in animal-related vehicular damage, a few states now have sophisticated systems to protect motorists from large animals. One of these systems is called the Roadway Animal Detection System (RADS). A solar powered sensor can detect large animals such as deer, bear, elk, and moose near the roadway, and thereafter flash a light to alert oncoming drivers. The sensor's detection distance ranges from 650 feet to unlimited, depending on the terrain.
Eating roadkill 
Cultural aspects 
- The fact that most people's encounters with roadkill occur long enough after the time of death for the carcass to be further macerated by traffic, or begin to decompose, has contributed to strong negative or ironic cultural associations and taboos. For example, when the Tennessee legislature attempted to legalize the use of accidentally killed animals, they became the subject of stereotyping and derisive humor. Songwriter and performer Loudon Wainwright III released his deadpan humorous song "Dead Skunk (in the Middle of the Road)" in 1972, and it peaked at number 16 on the Billboard Hot 100 rankings.
- Roadkill is sometimes used as an art form. Several artists use traditional taxidermy preparation in their works whilst others explore different artforms. International artist Claudia Terstappen photographs roadkill <http://www.claudiaterstappen.com/roadkill.html> and produces enormous prints which see the animals floating eerily in a void. Roadkill as art is not new, American artist Stephen Paternite has been exhibiting roadkill pieces since the 1970s.
Intentional collisions 
Research conducted in Ontario, Canada in 1996 found a high number of reptiles killed on not normally travelled portions of the road, which led to the presumption that some drivers intentionally run over reptiles. To verify this hypothesis, an experimental research was conducted in 2007, which found that 2.7% of motorists intentionally hit reptiles such as snakes and turtles. The rate of intentional hits was five times higher for male drivers.
See also 
Further reading 
- Roger M. Knutson: Common Animals of Roads, Street, and Highway: A Field Guide To Flattened Fauna.
- "Report shows high animal road kill toll in Tasmania". Abc.net.au. 2005-11-24. Retrieved 2013-02-20.
- Malia Wollan: "Mapping Traffic’s Toll on Wildlife" in The New York Times, September 12, 2010
- Erritzoe J., Mazgajski T. D., Rejt Ł. 2003. Bird casualties on European roads — a review. Acta Ornithol. 38: 77–93.
- Road kills: Assessing insect casualties using flagship taxon[dead link]
- Alistair J. Hobday and Melinda L. Minstrell: "Distribution and abundance of roadkill on Tasmanian highways: human management options", in Wildlife Research, nr. 35 1998
- "Roadkill 2007 – Summary of Past Data". Roadkill.edutel.com. Retrieved 2013-02-20.
- "Animal People Newspaper". Animalpeoplenews.org. Retrieved 2013-02-20.
- "wildlifecrossing.net/california". Wildlifecrossing.net. Retrieved 2013-02-20.
- "wildlifecrossing.net/maine". Wildlifecrossing.net. Retrieved 2013-02-20.
- "Roadkill — Wildlife Collision Mortalities | IFWIS". Fishandgame.idaho.gov. Retrieved 2013-02-20.
- "th.gov.bc.ca". th.gov.bc.ca. Retrieved 2013-02-20.
- "th.gov.bc.ca". th.gov.bc.ca. Retrieved 2013-02-20.
- Palmer, Janice. "Deer-Whistles Ineffective, Says Bioacoustics Researcher." November 2002. 21 November 2008
- Marshall, Edward (March 31, 2008). "Squirrel blamed for accident: Couple struck head-on after woman swerves to avoid animal". The Journal (Martinsburg, WV). Retrieved 6 May 2012.
- "Driver says squirrels made him crash into garage". Chicago Sun-Times. October 3, 2011. Retrieved 19 April 2012.
- "Confused squirrel causes three-car accident". South Whidbey Record. Sound Publishing Inc. 25 Jun 2008. Retrieved 19 April 2012.
- "Swerving can be worse than hitting animal on road". USA Today. 11 Jan 2012. Retrieved 6 May 2012.
- "Animal Vehicle Crash Mitigation," Oregon Department of Transportation
- Roadway Animal Detection System, Sensor Technologies & Systems, Inc.
- Animal Detection System, Safeguards Technology, LLC
- "Fencing to protect ponies". BBC News. 2009-01-21. Retrieved 2010-04-10.
- Firestone, David (1999-03-14). "Statehouse Journal; A Road-Kill Proposal Is Food for Jokesters". The New York Times. Retrieved 2010-04-10.
- Dead Skunk Songfacts.
- "After Life".
- "Roadkill artist speaks of controversial work". Stroud News & Journal. Retrieved 2007-10-16.
- E. Paul Ashley et. al. "Incidence of Intentional Vehicle–Reptile Collisions", in Human Dimensions of Wildlife, nr.12, 2007
- "Roger M. Knutson". Biology.luther.edu. 2013-02-15. Retrieved 2013-02-20.
|Wikimedia Commons has media related to: Roadkill|
- Roadkill Observation System in the US states of California and Maine
- Map Road Kill in Ireland
- Just Because It's In Slow Motion Doesn't Mean You Can Stop It - Joy Hunsberger—an artist who has been photographing roadkill as a form of ancestor worship since 1997.
-  Roadkill prevention in the Northern Beaches of Sydney Australia