AUDITORY SENSITIVITY IN THE BULLHEAD CATFISH ( Ictalurus nebulosis )

Abstract

Abstract.-The auditory sensitivity of 4 specimens of the bullhead catfish (Ictalurus nebulosis) was determined by shock-avoidance training in an aquatic shuttle box. The range of hearing extended from 100 to 4000 cycles per second, with the maximum sensitivity around 600 to 700 cycles per second.Previous work by Stetter1 indicated that bullhead catfish, then called Ameiurus nebulosus, had a hearing range extending to 13,139 cycles per second (Hz). Poggendorf2 also tested the auditory range of a single specimen of bullhead catfish but did not find sensitivity beyond the 5000 Hz limit commonly reported in the general literature for fishes. Because the structure of the fish ear, which involves macular organs weighted with large otoliths, does not appear to be suitable for high frequency response,3 the auditory range of the bullhead catfish needs careful reassessment.Procedure. The unconditioned shock stimulus was provided by the 110 v a-c line stepped down through an isolation transformer and a variable autotransformer and switch-operated to give 0-24 v a-c pulses between wire-grid electrodes on the sides of the tank. The shock level was found to be most effective at 5 v a-c.The intertrial interval, the trial duration, and conditioned-unconditioned stimulus interval were monitored by two Standard Electric Time Company model S-1 clocks. A Digital Electronics Company Digiac 3010 computer controlled the intertrial interval, the conditioned-unconditioned stimulus interval, and the presentation or termination of both the tonal and shock stimuli. The computer was programmed to vary the intertrial interval between 47-, 60-, and 73-second periods to 1)r'Vellt, time conditioning. Six Clairex type CL707 HI, photocells, placed in a vertical array three on each side of the barrier opposite 12 v bulbs, detected the movement of the subject across the barrier and provided the d-c pulse required to trigger the computer. The lamps and photocells were powered by three Electro Products model EC-2 power supplies.

The hearing of the Atlantic Salmon, Salmo salar

“…These fish belong to the ostariophysii-a group which includes the carp, electric eel, and catfish. One species, the freshwater catfish Ictalurus (= Ameiurus) nebulosus has been very assiduously studied, first by von Frisch (1923) and later by Poggendorf (1952) and Weiss, Strother & Hartig (1969). Poggendorf employed a special acoustic tank, with a sound projector in the floor, where sound pressure showed a sharply decreasing gradient towards the water surface, the particle motion varying in reverse.…”

Does the Hearing Sensitivity in Thorny Catfishes Depend on Swim Bladder Morphology?

“…Among catfishes, hearing abilities were measured in representatives of 11 out of 36 families: in doradids, pimelodids (long-whiskered catfishes), callichthyids, ariids, pseudopimelodids, malapterurids, heptapterids, mochokids, auchenipterids, silurids (sheatfishes) and ictalurids (North American freshwater catfishes) [19], [32]–[38]. Lechner and Ladich (2008) [19] showed in a comparative investigation on representatives of eight catfish families that species which have large unpaired swim bladders and 3–4 Weberian ossicles hear better above 1 kHz than species which have tiny and encapsulated bladders and only 1–2 ossicles.…”

Did Auditory Sensitivity and Vocalization Evolve Independently in Otophysan Fishes?

“…Discrepancies of 30-60 dB at particular frequencies were found in several species including the cod Gadus morhua and the goldfish C. auratus [Hawkins, 1981], the bullhead catfish Ictalurus nebulosus [Poggendorf, 1952;Weiss et al, 1969] and the blue gourami Trichogaster trichopterus [Saidel and Popper, 1987;Ladich and Yan, 1998]. These differences could be attributed partly to varying ambient noise levels, near field conditions (air loudspeaker vs. underwater speaker), different conditioning techniques (heart rate, food reward), surgery (saccular microphonics) and probably stimulus duration (e.g.…”