Get reliable science

Conversion of native grassland to non-native grasses poses a threat to grassland birds, including northern bobwhites (Colinus virginianus). Coastal bermudagrass (Cynodon dactylon) is a non-native grass that is planted widely for cattle grazing in the southeastern United States. The objectives of this study were to document and compare bobwhite abundance and survival on coastal bermudagrass pasture, a native shrubland community, and a former coastal bermudagrass pasture restored to native vegetation. In addition, we compared bobwhite habitat on these sites and 2 additional restored sites. We separated the bermudagrass sites into 2 sites for vegetation sampling. On these sites, we sampled vegetation using fifteen 25-m transects. We monitored relative abundance of bobwhites from trapping and whistle-counts. Bobwhite site use and survival was documented using radio-telemetry. During 2014, we trapped 105 individual bobwhites in the restored site, 27 in native shrubland, and 4 in the bermudagrass sites. These results coincided with our habitat results; the restored site had 6.26 times more grass clumps suitable for nesting than bermudagrass site 2 and nearly 13 times more than bermudagrass site 1. During 2015, we trapped 77 bobwhites in the restored site, 24 in native shrubland, and 34 in the bermudagrass sites. The habitat was drastically different in 2015, with the restored site providing a similar density of suitable nesting clumps as the bermudagrass site 2 and just over twice as many as the bermudagrass site 1. The cause of this difference was high spring precipitation and low levels of grazing on the bermudagrass sites in 2015. To our knowledge, this is the first study to quantify the effects of bermudagrass pasture on bobwhite abundance. This study reinforces the hypothesis that bermudagrass provides poor habitat for bobwhites and that bobwhite habitat can be successfully restored in pasture previously dominated by bermudagrass.