Summer and autumn movement ecology of native brook trout ( Salvelinus fontinalis ) in urban headwater streams of Eastern North America

Urban streams are impacted by multiple anthropogenic environmental stressors that exert considerable pressure on resident fish populations. Species such as brook trout ( Salvelinus fontinalis ) are particularly vulnerable because urban environments typically limit the cold oxygenated water required by all life stages. To understand factors associated with native brook trout movement in urban streams, we monitored 20 radio-tagged individuals from late summer through the spawning season in autumn, and modelled how movement was influenced by body size and habitat. Tracking occurred in two adjacent streams that differed in forest cover and channelization. In both streams, brook trout mainly travelled upstream, particularly at the onset of the autumn spawning season. Larger individuals exhibited greater movements, and habitat complexity imposed stronger effects in larger individuals. Greater movements were made into locations of shallower depth and lower conductivity, although these factors were conflated with movement into upstream locations. This study addresses a fundamental knowledge gap in urban stream ecology by providing detailed information on the movement of a key indicator species of aquatic ecosystem health.