Full Description

"Both species produce a short agonistic grunt call, and males produce a longduration tonal boatwhistle advertisement call (Tavolga 1958). The oyster toadfish boatwhistle is a single boop note (Fine 1978; Barimo & Fine 1998; Edds-Walton et al. 2002)"

"Opsanus tau and O. beta typically produce zero to several calls per minute (Breder 1968; Fine et al. 1977; Thorson & Fine 2002b). Opsanus tau produce spontaneous calls at rates as high as 10/min (Fine et al. 1977) and they can be induced to produce 14-16 calls/min for 3 min by optimized playbacks (Fish 1972). By chance, Fish (1972) witnessed a male O. tau produce 25 calls for a minute as a female swam into its nest, and similar short calling bursts have been recoded in O. beta (Thorson & Fine 2002b)."

"Finally, in addition to calling more rapidly in response to other callers, the Gulf and oyster toadfishes have developed an energy-saving response, termed acoustic tagging (Thorson & Fine 2002a), in which a male produces a grunt shortly after the onset of another male’s long-duration boatwhistle. The short grunt requires several muscle contractions compared to many in the long-duration boatwhistle. These tags suggest a dominance hierarchy because the presumed dominant male can tag boatwhistles of other males without being reciprocally tagged. Tagging is probably directed at eavesdropping females attending to male boatwhistles."

"Stimulation at 200 Hz evoked a boatwhistlelike sound with a fundamental frequency of 200 Hz induced by bladder movements every 5 ms (Fig. 1). Responses were robust to 2 min although there was evidence of decreasing amplitude of motion and sound towards the end of stimulus trains. After 3 min, swimbladder motion and sound amplitude were markedly reduced, although action potentials were still robust."

"A typical boatwhistle call of the oyster toadfish has a fundamental frequency around 200 Hz, requiring 200 muscle contractions/s (Skoglund 1961; Fine 1978; Barimo & Fine 1998)."

"Female sonic muscles are smaller, composed of larger fibres (Fine et al. 1990) and contain fewer mitochondria than those of males (Appelt et al. 1991), but females are capable of producing robust grunt calls equivalent to those of males (Waybright et al. 1990), and our study indicates similar glycogen use for the same task."

Observation Environment Quotes

"Oyster toadfish Opsanus tau were obtained from the York River, Virginia and maintained in a closed 20%0 sea water system. Protocols were approved by the Virginia Commonwealth University Animal Care and Use Committee."

Behaviour Description Quotes

"Both species produce a short agonistic grunt call, and males produce a longduration tonal boatwhistle advertisement call (Tavolga 1958). The oyster toadfish boatwhistle is a single boop note (Fine 1978; Barimo & Fine 1998; Edds-Walton et al. 2002)"

"Fish, tested from November to the middle of May, were anaesthetized in 200 mg/litre of MS-222 and placed ventral-side up in a Plexiglas holding tank. A pump system recirculated water containing 100 mg/litre of MS-222 over the gills. An incision was made on the ventral surface to expose the swimbladder and sonic nerve, and a silver bipolar hook electrode was placed around the left sonic nerve. The nerve was stimulated with a Grass S11 Stimulator and two PSIU6 Stimulus Isolation Units. Starting at a stimulation current of 1 mA, single 0.1 ms pulses were increased in 0.5 mA increments to obtain maximum fibre recruitment."

"We used a modification of Burke’s fatigue protocol (Burke et al. 1973) and stimulated the sonic nerve with 100 ms trains at 200 Hz every 4 s for 5 min. The original fatigue index used stimulus trains of 100 ms and frequencies of 90 Hz for 5 min, but we increased the frequency to test the muscle. Coincidentally, 15 calls/min is the most rapid rate that calling fish in the field would boatwhistle in response to experimental playbacks (Fish 1972), but the 100 ms stimuli are shorter than York River boatwhistles, which average about 300 ms (Fine 1978; Barimo & Fine 1998)."

Sound Name Quotes

"Both species produce a short agonistic grunt call, and males produce a longduration tonal boatwhistle advertisement call (Tavolga 1958). The oyster toadfish boatwhistle is a single boop note (Fine 1978; Barimo & Fine 1998; Edds-Walton et al. 2002)"