Distribution patterns in the larvae of two chironomid species with contrasting ecological traits, Chironomus anthracinus Zetterstedt and Procladius signatus (Zetterstedt), were examined by taking replicate samples from Lough Neagh, Northern Ireland. The two species showed clear differences in both vertical and horizontal distributions. In terms of vertical distribution P. signatus larvae were restricted to the top 3 cm layer of sediment, while C. anthracinus larvae were most abundant in the 3-9 cm layer. Larvae rarely occurred below 12 cm of the sediment surface. In terms of horizontal distribution the two species departed significantly from random distribution, though the patterns of dispersion were different between the two. P. signatus demonstrated a more strongly aggregated pattern than C. anthracinus. The latter species showed a tendency towards a regular distribution, which may be related to its sedentary, territorial habit. Observed differences in spatial distribution between these two species may be typical of herbivorous vs. omnivorous/carnivorous species of chironomid inhabiting lake sediments.
All Science Journal Classification (ASJC) codes
- Ecology, Evolution, Behavior and Systematics
- Aquatic Science
- Insect Science