Influence of the water mite Hydrachna conjecta on the population of the corixid Sigara striata (Hemiptera)

Summary

1.	The water mite Hydrachna conjecta consumes in its lifetime about 200 eggs of the corixid Sigara striata, the average being 4.5 eggs per day. In nature the consumption per day is probably higher.
2.	The egg production of S. striata is dependent on temperature. At a temperature of 16–20 °C they produce about 16 eggs per week. The mean production per female is 140 eggs. In nature the egg production might be higher.
3.	At an infestation rate of 10%, H. conjecta take away about 25–35% of the egg production of the spring generation of S. striata.