FONTAINE, JOSEPH/J*; MARTIN, THOMAS/E; University of Montana; University of Montana: Reproductive responses to experimentally reduced nest predation risk

The reproductive strategy that an individual adopts has long term fitness implications for itself and its offspring. These fitness consequences result in strong selection to express optimal life history and parental care behaviors. Yet, while there is clear variation in reproductive strategies both within and among species, little is known about what environmental factors lead to this variation. For the first time we provide clear experimental evidence that variation in the risk of juvenile mortality across landscapes can induce parents to alter their reproductive strategy. Parents of twelve species of passerine birds exposed to environments with experimentally reduced juvenile predation risk altered their reproductive strategy by increasing their investment in important life history traits such as egg size and clutch mass, as well as altering a suite of parental care behaviors.