Bird communities of jack pine and red pine stand types in Michigan: Implications of multi-versus single-species management

The approach of managing one habitat for one species has been criticized for its neglect of overall conservation of avian species richness. Nevertheless, a single vegetation type-young even-aged jack pine (Pinus banksiana)-has been planted extensively in northern Michigan, USA, to restore populations of a single species, the Kirtland's Warbler (Setophaga kirtlandii). Kirtland's Warblers are also known to use red pine (P. resinosa) as breeding habitat, leading us to consider how the conversion of jack pine to red pine might affect avian species other than the Kirtland's Warbler. We hypothesized that there would be no differences in avian species richness or diversity in jack pine and red pine communities of similar age, density, and canopy closure characteristics, all of which are important components of overall physical vegetation structure. We modeled avian communities in selected jack pine and red pine stands using nonmetric multidimensional scaling (NMDS). Overall avian species richness and diversity in jack pine and red pine stands were similar, but community ordination identified distinct compositions in each stand type. Of 23 resident species, 17 (77%) were more abundant in red pine, but the Kirtland's Warbler and Upland Sandpiper (Bartramia longicauda), two species of conservation concern, resided only in jack pine. The similarity of bird communities in stand types with different tree species but with similar tree densities and ground cover suggested that overall vegetation density and structure may be more important determinants of habitat choice than individual plant species. Increasing the number of red pine stands with age and density distributions similar to jack pine stands used by Kirtland's Warblers might create avian communities distinct from those in jack pine, but managers should consider the effects of such changes for both rarer species and overall avian species richness. Received 29 June 2022. Accepted 11 August 2023.