Moose Foraging in the Temperate Forests of Massachusetts

The "re-wilding" of ecosystems with extirpated large mammals has become a focus of recent scientific and conservation initiatives; however, it is unclear how proposed re-introductions will influence systems that are often vastly different from those that occurred before these animals were extirpated. Moose, the northeast’s largest Holocene browser, have recently expanded across southern New England’s temperate forest landscape after an absence of 200 years, realizing a natural re-wilding experiment. Moose have been well-studied throughout the boreal forest biome; however, because they are rare today in temperate forests, almost nothing is known of their ecology, behavior, or potential impacts to these ecosystems. This study investigated patterns of winter moose browse in order to: (1) gain insight into the likely influences of this herbivore on the vegetation patterns of the region; and (2) to identify the most important habitat features influencing moose winter foraging activity at a landscape and site scale. Two large forested watersheds in Central Massachusetts were sampled for moose browse, habitat features, and disturbances including forest harvesting and human activity. Chi-square and t-tests were used to identify browse species preferences of moose, and step-wise multiple regression was used to identify habitat variables that are strong predictors of browse intensity. Hardwoods and hemlock were favored over white pine, and browse intensity was significantly and positively related to forest harvesting, elevation, swamps, and distance to human settlement. The results from this study suggest that in the winter months, moose populations are concentrating in remote, elevated areas that are broken by swamps and have intensive forest harvests. In areas that support high moose densities, selective browsing, particularly in regenerating harvests, could promote less favored species like white pine at the expense of hardwoods and hemlock. The strong association between moose and forest harvesting indicates that recolonizing megafauna may interact with novel human conditions and disturbances to impact ecosystems differently than in the past. Nonetheless, habitat loss and climate change may ultimately preclude the long-term viability of moose and its impacts to this region