Clearcut stand size and scrub-successional bird assemblages

We investigated the effects of clearcut stand size on species richness, rep roductive effort, and relative abundance of scrub-successional birds and th e entire bird assemblage at the Savannah River Site in South Carolina. We u sed standardized mist net grids to mark and recapture birds in clearcuts re planted with longleaf pine (Pinus palustris) in stands of 2 to 57 ha that w ere two to six years old. Species richness for the entire bird assemblage w as not explained by stand size (P = 0.67), stand age (P = 0.95), or the int eraction of these two variables (P = 0.90). Similarly, species richness of scrub-successional birds was not explained by stand size (P = 0.63), stand age (P = 0.55), or the interaction of stand size and stand age (P = 0.35). Regressing species richness on clearcut stand size, we found a significant negative relationship between these variables for the entire bird assemblag e (P = 0.01) and for scrub-successional birds (P = 0.02). The ratio of juve niles to adults in mist-net samples varied by year (P = 0.04), but neither clearcut size (P = 0.23) nor the interaction of clearcut size and year (P = 0.25) was related to the ratio of juveniles to adults in the sample. We fo und no relationship between the frequency of capture of any category of bir ds and stand size (scrub-successional, P = 0.52; woodland, P = 0.77; combin ed sample, P = 0.55). Neither bird-species richness, reproductive effort, n or relative abundance differed across clearcut stand sizes. Clearcut stand size does not appear to be an important management variable if variation in species richness, reproductive effort, or relative abundance are objective s. We suggest that even-aged forestry is a useful tool for managing birds i n the southeastern United States.