Corixidae (Hemiptera Heteroptera) in two artifical lakes on Irish cutaway raised bog

Oceanic raised bogs have long been exploited, both commercially and privately in Ireland. At present, 23,628 ha or 8% remains in an active state (Foss 1998), while at least 60,000 ha will be cutaway by the middle of the next century (Egan 1998). Industrial exploitation through milling involves the gradual removal of layers of peat until the less combustible fen peat is reached. On abandonment, the substrate is generally a mix of acid and alkaline peats and even occasionally lake marl and boulder clay. The surface level tends to be below the average water-table and in recent years areas of cutaway have been flooded to create lakes. Water is chiefly supplied by groundwater and precipitation, but some lakes may be fed by drains or small streams. these water-bodies have been allowed to colonise naturally.

The development of macroinvertebrate communities was studied in two such lakes in central Ireland. As part of a wider investigation, Corixidae were sampled regularly over the course of a year and the animals examined. Interesting comparisons between sexes and between lakes were made.