Ask A Scientist

What happens to road kill’s bones and organs?

Asked by: Lauren Hyde
School: Owego Elementary School
Grade: 5
Teacher: Trevor McCloe
Hobbies/Interests: Exploring my creek
Career Interest: Marine Biologist or Lawyer

Answer from Peter Stahl

Associate Professor, Binghamton University

Academic Area: South American archaeology, zooarchaeology, vertebrate taphonomy, neotropical and historical ecology
Ph.D. school: University of Illinois
Family: Wife, Ann, archaeologist; children: Christina, food analyst, Emma, tenth grade Vestal HS
Interests/hobbies: Music, sports, running, tropical fish
Web page address:

Our landscapes are always littered with an assortment of dead things. We just don’t often see them because they are quickly buried, decompose, or are eventually scavenged by other animals.  Ultimately every living organism ends up being recycled, unless of course it happens to be one of those few whose remnants are preserved for some reason. Even in these cases, the inevitable is only delayed. Road deaths are highly visible examples of death and decomposition, primarily because they are in full view of the motoring public, which is partly to blame for the misfortune in the first place.  According to a recent New York Times article, one insurance company estimates that over 63,000 deer are hit and killed by motorists in the state, and in 2006, the Department of Transportation cleaned up more than 20,000 deer on our highways.  Of course, many other kinds of animals end up as road pizza, but deer are often the most noticeable victims.  This is common during mating season, when male deer are more interested in tracking the scent of female deer than avoiding human motorists, especially at the end of daylight savings time when periods of peak driving and deer activity collide, in a very real sense. It is the task of local and state transportation agencies to keep our roads safe, and that includes removing carcasses from major thoroughfares.  Road kill can cause further accidents, attract scavenging animals which can meet the same fate as their potential meal, contribute to the spread of disease and pollution, or just be downright gross.  Removal can be done either by transportation employees or through contracts with companies that specialize in taking away carcasses.  Although the Department of Environmental Conservation doesn’t have any guidelines for removing road kill, they are illegal to possess unless you have a special license (I’ve had one of these for years because of my interest in skeletons).  In some cases, police may issue possession permits to motorists who accidentally kill bear, deer, or moose on roadways so that they can be consumed for meat; otherwise, they can’t be used for organizations like food kitchens because their meat must first be certified by the United States Department of Agriculture.  However, zoos sometimes accept fresh road kill to feed their animals.  Sometimes, individuals voluntarily remove potentially hazardous, stinky, and generally unpleasant road kill on their own.  You can even find web-based instructions on how to remove road kill (, but then again you can just about find anything on the internet.  However, in many cases like country roads which aren’t heavily traveled, the residue of dead animals is often left to natural processes for disposal. You would think that much of the collected road kill ends up dumped in some out-of-the-way place or in municipal land fills, and these were certainly the ultimate resting places of choice for many years.  However, as the number of animal (especially deer) fatalities increases and solid waste facilities are pressured into prohibiting the dumping of carcasses, composting has become an environmentally acceptable response.  Farmers have been doing this for years. In a large composting bin, layers of carcasses are alternately placed back to back between surrounding layers of damp wood chips.  During composting, this layer-cake of dead animals and wood chips reaches internal temperatures of up to 150°F which breaks down carcass tissue. After a few months the compost can be used for more composting or distributed within highway right-of-ways.  

Last Updated: 3/1/17