Recurring Seasonal and Diel Movements of Common Carp in Interconnected Systems: Implications for Integrated Pest Management

In north temperate regions, invasive adult common carp (Cyprinus carpio) demonstrate complex patterns of movement which include aggregating in deep lakes during the winter and undertaking partial migrations to shallow lakes in the spring.  Although neither the nature nor causes of these movements are presently well understood, they have already proven useful to carp control. To improve on this understanding, we are studying carp movement in the Rice Creek Watershed District, a large, interconnected system of lakes in Minnesota, to describe both diel and seasonal movement patterns using radio telemetry. Seasonal tracking found the majority of carp (82%) migrated to shallow lakes to spawn and feed in the spring from a deep lake.  In the winter, all carp formed one aggregation in this deep lake.  Studies of diel movements found variable rates of movement between individuals and seasons. Large diel movements (1000 m/h) in the summer suggested nocturnal feeding behavior while diel movements in the winter appeared to correlate with shoaling behaviors. These patterns provide guidance for integrated pest management strategies that include targeting winter aggregations via under-ice seining , stream trapping, and baiting nets in the summer to exploit nocturnal feeding.  (Rice Creek Watershed District , National Science Foundation)