The coastal city of Pacific Grove in Monterey County, Calif. is known as "Butterfly Town, U.S.A." for the annual migration of the Monarch butterflies. The Monarch Butterfly Grove Sanctuary in the town is one of the oldest Monarch over-wintering sights in California, but in recent years their numbers have been dwindling rapidly. In 2009, the city heavily pruned branches, and gaps in the tree canopy resulted in Monarch numbers dropping from nearly 18,000 to under 800. "Butterfly Town, USA" centers on a community of activists, led by Bob Pacelli, who took action to save the Monarch Butterfly Grove Sanctuary. Pacelli and a group of volunteers planted 40 boxed trees to buffer the impact of the trimming. As a result, Monarch numbers increased by more than 500%. Motivated by their progress, more trees were planted which led to a clash between activists and the city about how best to protect the over-wintering site. "Butterfly Town, USA" focuses on the local habitat protection for the Sanctuary, but also on a larger goal: citizens working together globally to limit habitat loss due to climate change, deforestation and pesticides.