Meeting Abstract

P2.106  Jan. 5  Respiration of laboratory-reared midge fly larvae MCCLARY, Marion*; YASMIN, Rezwana; EDWARDS, Tiffany; Fairleigh Dickinson University; John F. Kennedy High School; John F. Kennedy High School mcclary@fdu.edu

Midge fly larvae are known to be one of few animals that can survive in polluted environments. Many polluted environments tend to have low levels of oxygen. Midge fly larvae are so adapted to these environments that their respiration rate is independent of external oxygen levels until such levels are very low. At such levels their respiration becomes dependent upon external oxygen levels and their oxygen uptake slows down. Respiration studies on small animals such as these are usually done with several individuals. However due to the need to study individual larvae, a special experimental condition was sought. The purpose of this study was to determine the volume of water needed to determine, within three to four hours, if oxygen uptake of the midge fly larva, Chironomous riparius, is dependent upon external oxygen levels, independent of external oxygen levels, or both. One or two midge fly larvae were placed into an air-tight tube that contained 1-2 ml of aerated spring water and the oxygen that they consumed was measured hourly with an oxygen probe. In most cases oxygen uptake increased at low oxygen levels when it should have decreased. The data indicate that the larvae were suffocating. Some larvae died during the experiment. It was concluded that laboratory larvae reared in an oxygen-rich environment are not adapted to low levels of oxygen. Future studies will compare field collected larvae to laboratory-reared larvae to confirm the conclusion of this study.