LEKKING AND NESTING RESPONSE OF THE GREATER PRAIRIE-CHICKEN TO BURNING OF TALLGRASS PRAIRIE

In the southern Great Plains, the greater prairie-chicken (Tympanuchus cupido) is confined to tallgrass prairie, a habitat now largely converted to agriculture. Remaining prairie is highly fragmented and subjected to land management practices that greatly alter the ecosystem of this species. Chief among these practices are deliberate, large-scale spring burns associated with early intensive stocking of cattle. We used extensive data to infer how such fires affect the prairie-chicken's lekking and nesting behavior. From 1998 to 2000, 60-79.4% of our study area-a 45,000-ha expanse of tallgrass prairie in north-central Oklahoma-was burned in spring. Prairie-chickens tended to lek on unburned areas but not in a pattern that differed from random habitat choice. Leks on burns tended to be < 200 m from unburned prairie. Females strongly avoided nesting in areas burned in spring 1998 and 1999 (n > 25 nests/y). Nesting effort was poor in 2000, prohibiting statistical analysis, but 5 of 8 nests were on unburned prairie. Incorporating data from 1997 (n = 12 nests), only 14 of 74 nests were placed on burned prairie, and only 5 of the 64 nests from 1998 to 2000 were located on prairie burned all three of those years. Avoidance of burns was particularly strong before June. Despite strong avoidance, nest success did not differ between burned or unburned prairie. Our findings raise two concerns: 1) if leks are established only < 200 m from unburned prairie, then an increase in the proportion of burns may inhibit lek formation, and, more important, 2) if females avoid nesting on recent burns, then an increase in the proportion of burns may cause a female to concentrate nesting effort on small patches (or forego nesting). We recommend moderation of spring burning (e. g., patch burning) of tallgrass prairie, lest the greater prairie-chicken be driven further from its already piecemeal habitat.