Summit metabolic rate exhibits phenotypic flexibility with migration, but not latitude in a neotropical migrant, Parkesia noveboracensis

Abstract

Physiology–life history interactions suggest that birds living with a fast ‘pace-of-life’ should have higher metabolic capacity to provision higher reproductive activity. Previous work supports this, but does not consider migration. We measured summit metabolism (\(\dot{V}{\text{O}}_{{ 2\;{\text{summit}}}}\)) in Northern Waterthrush (Parkesia noveboracensis) while wintering in the Republic of Panama, migrating northwards through eastern North America, and while breeding in northeastern North America. \(\dot{V}{\text{O}}_{{ 2\;{\text{summit}}}}\) is similar between breeding and overwintering (non-migratory) and is significantly elevated in migration. These data suggest that migration is a driver of phenotypic flexibility in these birds and that migration, like winter survival, may be an important determinant of connections between life history and physiology.