Scientists piece together puzzle of dramatic wood thrush decline

For the past 50 years, the number of wood thrush (Hylocichla mustelina) that breed in the United States has decreased more than 60 percent. However, because wood thrush migrate thousands of miles each year between their breeding grounds in eastern North America and wintering grounds in tropical forests from southern Mexico to Colombia, scientists have had trouble pinpointing which part of the iconic species' annual migratory cycle is causing that decline. Scientists from the Smithsonian Migratory Bird Center (SMBC) at the Smithsonian Conservation Biology Institute (SCBI) have found that the steepest regional declines have likely been the result of loss of habitat on breeding grounds in North America.