Moose foraging in the temperate forests of southern New England: A natural re-wilding experiment

The “re-wilding” of landscapes with regionally extirpated large mammals or related substitutes is the focus of many scientific discussions and restoration goals; however, the potential impacts of these re-introductions is largely unknown. Moose, the largest browsers in the northeastern U.S., have recently expanded into southern New England after an absence of 200 years, providing a natural experiment that offers insight into the capacity for re-wildings to restore original processes. Moose are well-studied across the boreal forest; however, almost nothing is known of their ecology, behavior, or potential impacts at their former southern range limit in temperate forests. We investigated moose browse on woody plants to evaluate: (1) selective use of tree and shrub species (2) site and landscape factors influencing winter foraging and (3) potential impacts to vegetation composition. Two large forested watersheds in central Massachusetts were sampled for moose foraging, habitat features, and disturbances including forest harvesting and human settlement. Chi-square tests were used to identify browse species preferences, and step-wise multiple regression was used to identify habitat variables that are predictors of browse intensity. Several hardwoods and hemlock were strongly preferred over white pine. Browse intensity was significantly and positively related to forest harvesting, distance to human settlement, elevation, swamps, and shrub density. Combined, these results suggest that in regenerating harvests and swamps with thick, deciduous shrub layers that are removed from human settlement, intensive moose browse may generate a decline in hardwoods and hemlock and an increase in white pine. Moose are interacting with patterns of human settlement and forest harvesting in this predator-depleted landscape and may influence the composition and function of this temperate ecosystem in novel ways. Pervasive anthropogenic conditions in even the most remote locations and the strong potential for megafauna to interact with these novel conditions complicate restoration goals of re-wilding efforts