AMMONIUM EFFECTS ON CHEMORECEPTION AND PHYSIOLOGY OF THE RUSTY CRAYFISH, ORCONECTES RUSTICUS

TitleAMMONIUM EFFECTS ON CHEMORECEPTION AND PHYSIOLOGY OF THE RUSTY CRAYFISH, ORCONECTES RUSTICUS
Publication TypeThesis
Year of Publication2012
AuthorsKlotz KL
AdvisorMoore PA
Date Published08/2012
Thesis TypeMasters Thesis
Abstract

Sensory information is stimuli dispersed through the environment in multiple modalities. Signal detection of stimuli can be impaired when background noise is present. Background noise can include anthropogenic pollution, e.g. ammonium. Ammonium can disrupt communication in three ways: masking, sensory impairment, or physiological impairment. To test for these three hypotheses, crayfish pairs were sized-matched to 30% size difference and exposed to one of two exposures of ammonium: low exposure was 0.9 mg/L NH4 + and a high exposure of 9.0 mg/L NH4 + for eight days. A fighting test was completed the first day of the exposure and the eighth day of the exposure. Crayfish fighting pairs exposed to the low ammonium levels fought for a longer period of time, hypothesized to be a result from sensory impairment. Fighting pairs exposed to high ammonium levels fought for a shorter period of time compared to the control, which is predicted to be from physiological impairment. Changing the daily activity patterns of crayfish populations by manipulating the time spent fighting has disproportional impact on the ecosystem. Crayfish spend a deviated amount of time shredding detritus and mating, which affects nutrient cycling and predator-prey interactions in the ecosystem.