Feeding behavior of aquatic insects: Case studies on black fly and mosquito larvae

The study of feeding behavior in aquatic insects requires integrating a number of techniques. Light and scanning electron microscopy give three-dimensional images of the feeding apparatus needed to understand their structure, while cinematography allows frame-by-frame analysis of movements of the food collecting organs necessary to explain their function. Videography is used in two ways: to provide a record of feeding over time and, with microscopy, to show patterns of flow around the insects. This facilitates the construction of catalogs of feeding behaviors and aids in the interpretation of relationships between functional morphology and hydrodynamics. Experiments are then conducted to determine which foods are ingested from those available in the environment. We use examples of investigations on black fly larvae and mosquito larvae to illustrate this integrated approach to the study of feeding in suspension-feeding aquatic insects.