Bird and mammal diversity on woody biomass plantations in North America

In this paper, recent studies of birds and small mammals inhabiting Populus (hybrid poplar and cottonwood) plantations are summarized. Plantations provide habitat at least as favorable for native birds and mammals (as evidenced by overall density, species richness, and species composition) as agricultural croplands. However, by the same measures, plantation habitat is poorer quality than natural or semi-natural forest. Bird and small mammal species composition on plantations is a mixture of openland (crop and grassland) and forest species that is unique compared to other nearby habitats, and does not resemble that of either grasslands or forests. Plantations may not function as forest at either habitat or landscape scales. For highly mobile animals such as birds, landscape composition plays a central role in determining occupancy of plantations. For less mobile organisms, within-plantation habitat quality is more critical. Sources of non-uniformity in plantation vegetation are important determinants of occupancy. Although unplanned variation in vegetation structure occurs on some plantations, assuring the presence of heterogeneity may require specific planning. There is no evidence of altered population interactions (nest predation or parasitism, small-mammal population performance, or interchange among local populations) as a result of plantation establishment.