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- Info
A regional model of the eastern cottontail and land-use changes in Illinois
| Author: |
Mankin, P.C.; Warner, R.E. |
| Date: |
1999 |
| Periodical: |
Journal of Wildlife Management |
| Abstract: |
The eastern cottontail (Sylvilagus floridanus) is important in ecological food webs as a prey species for a wide variety of predators throughout its range, and is also a popular game animal. From 1956 to 1978, the eastern cottontail is estimated to have declined at least 70% in Illinois and more than 90% in the most intensively farmed regions of the state. We describe long-term changes in the index of relative abundance for the eastern cottontail in Illinois in relation to regional patterns of land use. Classification and regression trees (CART) analysis was used to analyze county-level changes in 6 land-use variables (row crops, hay, diverted cropland, woodland, small grains, pasture) in relation to the number of cottontails harvested per hunter per day, 1956-69 versus 1982-89. In the early period (1956-69), 78% of the counties had an index of at least 1.50 cottontails/hunter/day, compared to only 28% of the counties in the recent period (1982-89). The amounts of pasture, hay, and small grains were positively correlated (P < 0.01) with the change in cottontail index, and 2 response regions were identified with the change in pasture. The region with the least decline in cottontail index had more pasture, hay, and woodland. The stable amount of woodland during recent decades may have moderated the decline in cottontails, despite the negative influences of the other land-use changes. Long-term changes in the cottontail index in Illinois predictably track changes in farming and geomorphic factors that modify agriculture. Our analyses underscore the influence of agriculture on upland wildlife over expansive temporal and spatial scales in North America, influences that are not necessarily apparent in finer-scale studies. |
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