n amphibians in addition to turning them into pancakes. Chemical runoff from roads treated with de-icing chemicals has now been linked to mass mortaily of newts and was recently discovered to drastically reduce the size of egg masses in some frog species. In addition, Coffin reports in her 2007 paper that even simple traffic noise can affect animal behavior. Some birds, for example, (and perhaps some frogs, too) have to sing more loudly in the presence of traffic noise, thereby spending more energy on communication that could otherwise be used to find food or mates. Roads (divided highways in particular) act as significant barriers to dispersal and migration of animals, fragmenting habitat and genetically separating populations over time. Roads can also increase human access to rural areas, which can lead to increased hunting pressure and/or facilitate the spread of non-native species. “Cumulatively,” Coffin writes, “road-effects interact with each other when roads are considered as [eco]systems.”
Photographs of egg masses of a salamander (top) and wood frog (bottom) from forest and roadside pools in the Adirondack Mountain Region of New York from Nancy E. Karraker & James P. Gibbs' 2011 paper in the journal Hydrobiologica (Volume 664, Number 1, pgs 213-218) entitled, "Contrasting road effect signals in reproduction of long- versus short-lived amphibians".
“To educate better…We need to see the road through the eyes of the frog.” -Dr. Mark Widome, 1991
Roadkill has been the topic of several recent news articles and blogs by National Geographic, The New York Times and New Scientist. In fact, the problem of roadkill is so serious and understudied that The University of California at Davis recently formed the Road Ecology Center, dedicated to the emerging field of “road ecology”. Think roadkill is only a problem for wildlife? Think again. A 1991 article in the medical journal Pediatrics by Dr. Mark Windome used Frogger as an illustrative tool to describe the significant threat traffic crossings have on juvenile human survivorship (a problem that still abounds)!
Roadkill isn’t just on major highways, it even extends to protected areas. The photo below, for example, was taken along a relatively quiet park road between Buescher and Bastrop State Parks in Bastrop County, Texas. During a spring field trip in 2009, there were hundreds of roadkill frogs along Park Road 11 (this is “protected” habitat, folks!). Interestingly, the frog carcasses were all dominated by red imported fire ants (Solenopsis invicta) and could be facilitating the spread of these ants by providing convenient food supplies.
Unfortunately, Frogger isn't all fun and games. This particular individual made a meal for a colony of invasive red imported fire ants (Solenopsis invicta), potentially facilitating their spread. This photo was taken in a protected state park in Texas. Photo by H. Gillespie (2009).
So what’s being done about road mortality?
In a real-life examination of Frogger’s plight, Dr. Tom Langen and colleagues studied amphibian and reptile road mortality in upstate New York (reported in a 2009 article in the Journal of Wildlife Management). By simply recording when and where amphibian roadkill occurred, these scientists were able to identify “hotspots” of amphibian road mortality. These hotspots, mostly located where wetlands came within 100 meters of the road, can be used to determine where to place wildlife barriers, underground crossing tunnels and signs warning drivers to slow down and watch out. Knowledge of hotspots can even be used to predict and avoid where roadkill may be greatest when planning new roads.
All too often, however, the burden of “doing something” about roadkill falls to local citizens and organizations. For example, many citizen groups around the country have started amphibian crossing projects in their communities, to assist Frogger in crossing safely. Other groups also collect roadkill data through educational programs such as The Roadkill Project started by a professor from Simmons College in Boston to teach his students ab