An Improved Flow-through Respirometer for Aquatic Macroinvertebrate Bioenergetic Research

Abstract

An improved flow-through respirometer that is simple to construct and operate is described. Using an impedance monitoring system, activity-specific aerobic metabolism of macroinvertebrates can be quantified under controlled temperatures and oxygen tensions. Application of the respirometer is demonstrated by examining the activity-specific respiratory responses of two species of Hirudinoidea to 100% air-saturated conditions and differing levels of hypoxia. Acclimation time of the animals to the respirometer chambers is also investigated. Using this type of flow-through system for macroinvertebrate bioenergetic studies, activity-specific respiration measurements can be made under constant abiotic conditions and minimal disturbance to the animals.