Why an iPhone app?

We need your help! By downloading this app and using it even only occasionally, you are helping us better understand how many animals die along our roads and where and when road kill is likely to happen in the future. This information in turn will aid researchers, planners, and elected officials as well as local, state, and federal agencies seeking to improve public safety and minimize harm to wildlife.

While the idea of documenting the number of dead critters on our roadways sounds like a simple, easy thing to do, it isn’t. The shear amount of roads in any given section of our state or region is daunting. Driving these road networks on a regular basis is time consuming, costly, and (most importantly) generates a lot of pollution. We believe a better approach is to use you as our eyes and ears as much as possible. If you are already planning on driving to work, school, or the store tomorrow and are up to keeping an eye peeled for any road kill you may see, that amounts to us being able to collect this valuable information without the additional pollution we would have generated to do the same thing. In addition, no one has perfect eyesight nor is able to be everywhere simultaneously; the more eyes searching for kills, the more accurate and useful our database will become.

Isn’t someone already keeping track of dead animals?

Unfortunately, no one has yet to gather a long-term time series of road kill across our region. A great effort recently begun at UC Davis is attempting to do this and we are working on integrating our approaches, but by in large people have not collected this data consistently in the past.

While a deer or mountain lion getting struck by a car on a major freeway and snarling traffic might make the local news, we have no consistent regional accounting of how many animals die each year or where those deaths occur. The limited information that has been compiled is often collected by a handful of biologists from a university or consulting firm for a very brief period over a very narrow area (often along a single subsection of one roadway).

Most of these existing road kill datasets are compiled from accident reports or from road maintenance crews responsible for clearing large animal carcasses from roadways. While a great first step, such data collection efforts have several limitations:

  1. they ignore or underreport smaller critters such as raccoons, opossums, and squirrels that are unlikely to cause major damage or necessitate clean-up, but who comprise the bulk of the actual kills.
  2. they don’t allow us to accurately predict the rate of kills (as they do not report the times someone checked and found no kills).
  3. they run for a short time.

The upshot is that these traditional efforts to count animals killed on roads are likely skewed and should be taken to be minimum values only. To accurately predict the total amount of kills in an area per year or per day, we need to know both the number/locations of kills AND the number of days when/locations where no kills occurred. Therefore, noting the lack of road kill during your drive is as helpful to us as your documenting the presence of a kill. Knowing both kills and lack thereof greatly improves our understanding of how dangerous that particular road network is to both people and animals.

What kinds of questions will we be able to answer?

Our database already contains several thousand road surveys and over 2,000 observed kills. As you add to this data set, we (and you) will be able to answer questions such as:

  1. Where is the best place to put a wildlife crossing on a stretch of road?
  2. How many predators die each year in our county or state?
  3. Which species are most likely to be killed by vehicles?
  4. If we expand a freeway, how much more road-associated mortality are we likely to see over the next decade?

Where should we look for road kill?

Everywhere! Just about anywhere you drive is fair game. Data from multilane urban freeways are just as helpful as data from single-lane farm roads or two-lane winding roads through National Parks. The key thing here is to just make your trips as you normally would, but do so with more observant eyes (and the occasional pushing of a button on your iPhone). For improved accuracy and your safety, we request you only conduct observations during daylight hours with non-inclement weather (ideally with a passenger working the app).

Geographically speaking, our research group at California State University Channel Islands has been actively monitoring road kill inside the United States and across the globe for several years. The majority of our lab’s existing data have come from our focal research areas of southern California, southeastern Louisiana, and the eastern borderlands of the country of Turkey, with Californian observations comprising the bulk of our database (more 2,500 individual surveys having driven more that 20,000 miles/32,000 kilometers). Our hope is that this app will be used as broadly as possible. So while we are of course interested in data collection from the areas where we have been working, we hope to turn this into a much more useful, nationwide tool.

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