Heart rate was measured during three potentially stressful events. Firstly, trout were classified as bold or shy, using a novel object test. Subsequently, trout were implanted with biologgers to record heart rate in vivo at rest, during and after the behavioural tests. Following recovery, fish underwent a second novel object test, a confinement test, a pair-wise contest and a final novel object test to explore consistency of boldness over the experimental period.