Research projects associated with the University of Minnesota Insect Collection concern several aquatic and terrestrial groups. Many current projects focus on the systematics and biology of Trichoptera, an important order of aquatic insects.
Trichoptera, or caddisflies, are an important component of aquatic ecosystems around the world and are especially abundant in rivers and streams. Among the orders of aquatic insects, it is the most species diverse. The larvae are most familiar because of the interesting silken nets and portable cases they construct. Like caterpillars, Trichoptera larvae produce silk, and it is to the diverse ways in which silk is used to exploit various aquatic niches that the order owes its evolutionary success. Caddisfly larvae are of fundamental importance in aquatic food webs, where they serve primarily in nutrient processing and cycling. Adults, which are terrestrial and usually short lived, often go unnoticed, but it is this stage on which the taxonomy of the order is based. Currently about 10,000 species of Trichoptera are known worldwide. Knowledge of the taxonomy and ecology of the species has proven valuable in biomonitoring programs, because of the very different susceptibility of the various species to pollutants and other types of environmental disturbance.
Caddisfly species in temperate regions, especially North America and Europe, are well known, but the fauna of tropical regions is much less well known. 2,175 species have been recorded from the Neotropics, but this probably represents only a fraction of the actual fauna. This is significant because of the many threats to natural freshwater resources in South America – deforestation and siltation, pesticide and herbicide runoff, organic enrichment, thermal pollution, sewage contamination, and, potentially, acid rain, which even affects pristine headwaters. Biological monitoring programs using Trichoptera and other aquatic insects would be very useful in helping to track and regulate the impacts of these abuses. However, the development of biomonitoring protocols hinges on resolving the identity of the aquatic insect fauna, of which Trichoptera are a vital component.
More information on Trichoptera and the use of aquatic insects in biological monitoring of water quality:
North American Benthological Society
Monitoring Water Quality Homepage (EPA)
Return to Projects Page