Assessing the presence of monarch butterflies and milkweed habitat in Acadia National Park, Mount Desert Island, Maine

Smith, Erickson; Connery, Bruce

From the introduction: "Monarch butterflies are an easily recognized butterfly in Acadia National Park and across all of North America. Studies and surveys have documented dramatic population declines ranging from 50% - 90% in some areas of the Unites States with a reported 90% decline in Mexico (Jepsen et al. 2015). One explanation for these declines is habitat loss, how-ever many other issues are being explored. Similar declines had been noted for other pollinators, prompting the President to join scientists and managers in supporting and asking for additional studies and surveys assessing the causes of these declines. To help understand the decline, Superintendent Steele decided the park staff would work with scientists and conservation specialists across the country by protecting areas of milkweed habitat found in the park and being watchful for the adults and caterpillars. The young monarch caterpillars depend on milkweed plants to nourish them and give them a special chemical defense against predators, which they obtain from foraging on the sap of milkweed plants. Acadia National Park received special funding in 2015 to locate milkweed stands, conduct surveys for all monarch life stages, document adults, and build a database of area individuals and cooperators working on pollinators or monarch conservation and begin collaborative efforts."