LTREB: Stopover Biology of Intercontinental Landbird Migrants

University Of Southern Mississippi, Hattiesburg MS

Investigators

Abstract

Migration is a fundamental characteristic of the life history of many animals from monarch butterflies to humpback whales and is one of the most fascinating of all behavior. Over two-thirds of all songbirds that breed in temperate North America migrate long distances to wintering areas in Mexico, Central and South America and the Caribbean islands. Traveling long distances comes with considerable risks, and the mortality may be substantial. This research focuses on the problems migrants face when they pause to rest and refuel: Besides the energetic cost of flying, a migratory bird invariably finds herself in unfamiliar surroundings at a time when energy demands are high, often faced with avoiding predator avoidance and finding food, competing with other migrants and resident birds for limited resources, faced with unfavorable weather, and the need to correct orientation errors. Field studies are designed to determine how migrants solve these problems before and after crossing the Gulf of Mexico. Besides gaining a better understanding of how animals respond to periods of energetic demand, this research has important conservation implications. Evidence reveals population declines among many migratory bird species over the past quarter century. Although debate over the causes of the decline continues, what has been largely overlooked in development of conservation plans is the importance of habitat during migration. Unless habitat requirements during migration are met, conservation measures focused on the breeding grounds and/or tropical wintering areas will be compromised. We know little about how migratory birds respond to changes in the availability and distribution of stopover habitat.