Parmly faculty members are conducting studies on how Lake Michigan mottled sculpin use their lateral line system in detecting water motion created by the small vertebrate and invertebrate prey that they feed on.
Mottled sculpin are benthic fish that normally feed at night, when vision is severely restricted.
In the lab, blinded sculpin will respond to the vibrations of a nearby, chemically inert object, such as a small vibrating sphere, with an initial orientation towards the source, followed by a stepwise approach to the source. When the source is less than a few cm away, sculpin strike at the source as if it were food. Pharmacological or mechanical blocking of the lateral line system results in a complete disappearance of the orientation and subsequent approach and strike behavior, indicating that the lateral line system is extremely important in helping these fish locate nearby vibratory sources. Current experiments are designed to measure the ability of fish to localize a nearby, low frequency dipole source, or sinusoidally vibrating sphere. These experiments take advantage of the naturally-occurring feeding response of the mottled sculpin, which is used as a behavioral indicator of how well the fish can determine the location of the source.