Sound production, hearing and possible interception under ambient noise conditions in the topmouth minnow Pseudorasbora parva

Abstract

Sounds were produced by the topmouth minnow Pseudorasbora parva, a common Eurasian cyprinid, during feeding but not during intraspecific interactions. Feeding sounds were short broadband pulses with main energies between 100 and 800 Hz. They varied in their characteristics (number of single sounds per feeding sequence, sound duration and period, and sound pressure level) depending on the food type (chironomid larvae, Tubifex worms and flake food). The loudest sounds were emitted when food was taken up at the water surface, most probably reflecting 'suctorial' feeding. Auditory sensitivities were determined between 100 and 4000 Hz utilizing the auditory evoked potentials recording technique. Under laboratory conditions and in the presence of natural ambient noise recorded in Lake Neusiedl in eastern Austria, best hearing sensitivities were between 300 and 800 Hz (57 dB re 1 mPa v. 72 dB in the presence of ambient noise). Threshold-to-noise ratios were positively correlated to the sound frequency. The correlation between sound spectra and auditory thresholds revealed that P. parva can detect conspecific sounds up to 40 cm distance under ambient noise conditions. Thus, feeding sounds could serve as an auditory cue for the presence of food during foraging.

Auditory evoked potential audiometry in fish.

“…Similar results were achieved when presenting lake noise to the closely related topmouth minnow (both family Cyprinidae) (Fig. 59) (Scholz and Ladich 2006).…”

“…59 Hearing thresholds of the topmouth minnow Pseudorasbora parva during quiet laboratory conditions (baseline) and in the presence of ambient masking noise of Lake Neusiedl (93 dB). From Scholz and Ladich (2006) Genetic factors Albinism, a genetic abnormality of the melanin system in which the synthesis of this pigment is reduced or lacking, is occasionally associated with hearing impairments in mammals. Therefore, compared auditory thresholds in normally pigmented and albinotic specimens of two catfish species, the European wels Silurus glanis (family Siluridae) and the South American bronze catfish Corydoras aeneus (family Callichthyidae).…”

Mechanisms of Fish Sound Production

“…Feeding sounds have been investigated in several species and generally correspond to pulsed chewing sounds that occur during food grinding and manipulation by teeth of the pharyngeal jaws (Lobel 2001;Lagardère et al 2004;Scholz and Ladich 2006). We are uncertain if these sounds function in communication because nonspecialized morphological structures are involved and behavioral studies are lacking.…”

Animal perception in gravel-bed rivers: scales of sensing and environmental controls on sensory information

“…The creation and bursting of air bubbles creates loud acoustic signals. As a result, rivers can be noisy environments (sound levels often > 100 dB) with ubiquitous ambient noises that can severely mask the detection of important acoustic signals by animals (Wysocki and Ladich 2005;Scholz and Ladich 2006). Fish are differentially affected by acoustic masking.…”