Environmental Management

, Volume 41, Issue 6, pp 844–852 | Cite as

Diversity, Seasonality, and Context of Mammalian Roadkills in the Southern Great Plains

  • Brenda D. Smith-PattenEmail author
  • Michael A. Patten


Thousands of mammals are killed annually from vehicle collisions, making the issue an important one for conservation biologists and environmental managers. We recorded all readily identifiable kills on or immediately adjacent to roads in the southern Great Plains from March 2004–March 2007. We also recorded distance traveled, whether a road was paved or divided, the number of lanes, and prevailing habitat. Surveys were opportunistic and were conducted by car during conditions of good visibility. Over our 239 surveys and >16,500 km traveled, we recorded 1412 roadkills from 18 different mammal species (size ranged from Sciurus squirrels to the white-tailed deer, Odocolieus virginianus). The overall kill rate was 8.50 / 100 km. Four species were prone to collisions: the Virginia opossum (Didelphis virginiana), nine-banded armadillo (Dasypus novemcinctus), striped skunk (Mephitis mephitis), and northern raccoon (Procyon lotor). Together they accounted for approximately 85% (1198) of all roadkills. Mortality rate differed significantly between 2- and 4-lane roads (8.39 versus 7.79 / 100 km). Kill rates were significantly higher on paved versus unpaved roads (8.60 versus 3.65 / 100 km), but did not depend on whether a road was divided. Roadkills were higher in spring than in fall (1.5×), winter (1.4×), or summer (1.3×). The spring peak (in kills / 100 km) was driven chiefly by the armadillo (2.76 in spring/summer versus 0.73 in autumn/winter) and opossum (2.65 versus 1.47). By contrast, seasonality was dampened by a late winter/early spring peak in skunk mortalities, for which 41% occurred in the 6-week period of mid-February through March. The raccoon did not exhibit a strong seasonal pattern. Our data are consistent with dispersal patterns of these species. Our results underscore the high rate of highway mortality in the southern plains, as well as differences in seasonality and road type that contribute to mortality. Conservation and management efforts should focus on creating underpasses or using other means to reduce roadkill rates.


Dasypus novemcinctus Didelphis virginiana Dispersal Mephitis mephitis Procyon lotor Reproductive cycle Roadkill Seasonality 



In-kind support was provided by the Oklahoma Biological Survey, University of Oklahoma. Robert G. Newcombe supplied a key reprint and a helpful spreadsheet for calculating confidence intervals, which we used as a basis for our formulas. Robert C. Dowler discussed with us comparable seasonal patterns of skunks in Texas. Ray Jordan, County Engineer of Tulsa County, Oklahoma, answered our queries on roadkill clean up on local highways. We thank Shelley M. Alexander, Virginia M. Dale, Ian F. Spellerberg, and an anonymous referee for constructive comments on a draft.


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Copyright information

© Springer Science+Business Media, LLC 2008

Authors and Affiliations

  1. 1.Sam Noble Oklahoma Museum of Natural HistoryUniversity of OklahomaNormanUSA
  2. 2.Oklahoma Biological Survey and Department of ZoologyUniversity of OklahomaNormanUSA

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