218 Fish Behavior and Angling 



Some species prefer semi-darkness and are so sensitive to light that they 

 exhibit extreme agitation if forced to swim in illuminated clear water. 



Walleyes in Lake Gogebic (Michigan) were so sensitive to an auto- 

 mobile floodlight at close range that they would collide with rocks or 

 beach themselves in their attempts to escape.^^ 



Fingerling channel catfish being reared in turbid river water in wooden 

 hatchery troughs, exhibited extreme fright when clear water was turned 

 on them while the troughs were being cleaned. When black bullheads 

 are placed in an aquarium in strong light they tend to pile-up, each fish 

 trying to hide under the others. Smallmouth bass, red-ear sunfish, and 

 grass pike in laboratory tanks have been observed to die of shock when 

 the lights in the aquarium room were turned on at night. 



HEARING 



Laboratory experiments using modern equipment have established 

 that all species studied have the ability to hear. The range of tone per- 

 ception is believed to vary from 8 to 22,000 cycles per second. The "ears" 

 of fishes are internal and consist of a sacculus and lagena ( pars inferior ) 

 believed to be responsible for hearing, and a utriculus and semi-circular 

 canal system {'pars superior) concerned with equilibration. In some 

 species the pars superior may take part in the perception of tones. In 

 the Ostariophysi (examples are gold fish and yellow bullhead), the 

 connection of the air bladder with the "ear" by Weber's ossicles increases 

 the ability of fish to hear. Perception of very low frequencies is generally 

 attributed to sensory organs in the skin. 



Various species of common warm-water fishes have different ranges 

 of sound perception; for example, the range of the bluegill is 35 to 8960 

 cycles per second ^^ while that for the carp is 8 to 22,000.^- These ranges 

 cover a part of the range of human speech, but a great deal of intensity 

 is lost between air and water, so that it would be difficult for a fish to 

 hear a fisherman talking. This is not true for vibrations transmitted 

 through the bottom of a boat or from walking with "heavy feet" along 

 the water's edge. The disturbance caused by rowing or paddling where 

 the oarsman is careless about letting oars or paddle hit or scrape the edge 

 of the boat is undoubtedly heard by fishes. 



Sound Location 



Fish learned to distinguish between tones of different intensities and 

 were able to distinguish a change in frequency (one-fifth of an octave) 

 in a continuously sounding source. 



According to Kleerekoper and Chagnon,^^ creek chubs were able to 

 locate a source of vibration and move toward it along curved pathways 



