Importance of carolina bays to the avifauna of pinelands in the southeastern United States

摘要

Past anthropogenic activity has led to the destruction or alteration of Carolina bay wetlands throughout the southeastern United States. Presently, urban development, combined with a 2001 ruling by the US Supreme Court relaxing protection of isolated wetlands, poses an increasing threat to these and other isolated wetland systems; however, little information exists on the importance of these wetland systems to birds. We compared breeding and wintering bird communities of upland pine (Pinus spp.) forests with and without Carolina bays. Estimated species richness was greater in pine forests with Carolina bays than without during the winter (31.7 ± 1.3 [mean ± SE] vs. 26.9 ± 1.2; P = 0.027), but not in the breeding season (27.9 ± 2.2 vs. 26.3 ± 2.2; P = 0.644). Total relative abundance did not differ between pine forests with Carolina bays and those without in either the breeding (148.0 ± 16.0 vs. 129.4 ± 10.4 birds/40 ha; P = 0.675) or winter (253.0 ± 36.4 vs. 148.8 ± 15.1 birds/40 ha; P = 0.100) seasons. However, 23 species, 43% of which were wetland-dependent, were observed only in pine forests with bays during the breeding season, and 20 species, 30% of which were wetland-dependent, were observed only in such sites during winter. In contrast, only 6 and 1 species were observed only in pine forests without bays during the breeding and winter seasons, respectively, indicating that few species were negatively affected by the presence of bays. Thus, Carolina bays appear to enrich the avifauna of pine forests in the southeastern United States.