Introduction

Wildlife road kill provides a sampling of local wildlife and demonstrates a way that humans interact with nature. Students at Midlothian Middle School have studied wildlife road kill since 2001. During that time they discovered the most common road kill species is the gray squirrel, followed by opossum and raccoon ( 2001-02 school years ). This study also showed that squirrels, a diurnal species, were more likely to be killed in the fall, whereas the nocturnal opossum was more likely to be killed in the spring. In 2002, students mapped road kill and compared it with land use ( maps of road kill ). Species such as white-tailed deer were found to be killed near business parks and shopping centers, suggesting that they were entering these areas to browse at nighttime. Raccoons, a major carrier of rabies, were found near large parking lots, suggesting they were attracted to dumpsters.

Midlothian Middle School is in Chesterfield County, a western suburb of the Richmond , VA metropolitan area. This area can be described as an urban- wildland interface, where urban land uses are encroaching on mostly forest land, with some agricultural lands included. In 2005, students investigated changes in road kill over time. They compared their 2005 road kill data with 2002 data to see if any trends have occurred.

Methods

Each student monitored a section of road in their community once a week for a period of six weeks, October to November, 2005. For all road kills they recorded the species name and number observed. Road kills that remained on a road over one week were not counted twice. These methods were the same followed by the 2002 Midlothian students.

Dependent variable: Number killed

Independent variable: Year killed

Hypothesis: Road kill will be greater in 2005 than in 2002.

Results

Students were asked to graph their data and draw conclusions from their study. There was a rise in overall numbers of road kill in Midlothian from 2002 to 2005. Students believe this was caused by increased numbers of roads built, higher numbers of cars on the roads, increases in the wildlife population, and general loss of wildlife habitat due to development.

Students considered why some species had higher road kill numbers than others. Possible causes for higher number of squirrel kills were noted as loss of trees and more trees are now in close proximity to roads. There was a relationship drawn between lower number of natural predators and an increase in squirrel populations—as well as the fact that predatory birds feed on road kill so if their numbers decreased road kill may remain on the road longer and have a greater likelihood on being surveyed.

Students suggested ways that road kill could be reduced. Developers could build roads in areas where wildlife population is low, create barriers, such as fences, on sides of roads that border wildlife habitat, designate certain areas as wildlife habitat with no development, and increase street lights so animals can be seen better. Suggestions students could follow include carpools or walking to decrease numbers of automobiles, increase awareness of animals while in a car, ask one's parent or other driver to drive with more consideration for wildlife, and ask the community to post more animal crossing signs.

Students were asked to review their data collection methods and consider if there were experimental issues that would cause differences between 2002 and 2005. Possible issues were: different roads and miles of road being surveyed, different time of year, and number of participants in the survey changed.

Conclusions

The hypothesis that road kill would be greater in 2005 than in 2002 was supported by the data. This data can be used to explore trends in wildlife populations due to human interactions, and to suggest measures to reduce the number of road kill. The experiment could be improved by observing the same roads each year, and by keeping observation time the same (controlling for roads and observation time).