Anne-Laure Groison, Olav S. Kjesbu & Marc Suquet (2011): Sexual dimorphism of
drumming muscles in European hake (Merluccius merluccius). Environ. Biol.
Fishes 91 (1), 7-13.
Abstract: Dissections of mature and non-mature European hake males and females
(N = 142) collected in waters off the western coast of Norway and in the Bay of
Biscay (France) in 2004–2006 demonstrate for the first time that this gadoid
species contains drumming muscles. There were differences in drumming muscles
weight with body length, sex and maturity stage. This study shows that the
difference between females and males is primarily manifested during the
spawning season, seen both in the French and Norwegian samples. For the mature
females the drumming muscles dry weight increases only slightly, if at all,
with increase in total length. For mature males there is a corresponding rapid
increase. There does not seem to be any consistent difference between the
average dry weight of the drumming muscles in immature male and immature and
mature female hake of the same length, tested on the Norwegian samples. Our
results suggest that male hake, like the males of other gadoids studied, may
produce sounds in the context of spawning.
For reprints please contact Anne-Laure Groison (email:
Daniel E. Holt & Carol E. Johnston (2011): Hearing sensitivity in two black
bass species using the auditory brainstem response approach. Environ. Biol.
Fishes 91 (1), 121-126.
Abstract: Recently, several bioacoustic studies have focused on the red eye
bass (Micropterus coosae). One of these studies documented sound production,
while the other played back sounds produced by prey items in order to determine
their attractiveness to M. coosae. Surprisingly, the hearing ability of fishes
in the genus Micropterus has received very little attention. The need for
audiograms describing hearing in Micropterus is apparent. This study utilized
the auditory brainstem response (ABR) approach to determine hearing sensitivity
in terms of both sound pressure level (SPL) and particle acceleration in two
black bass species, the red eye bass (M. coosae) and the Alabama bass (M.
henshalli). Audiograms produced in this study expressed in both SPL and
particle acceleration showed a positive relationship between hearing threshold
and frequency. Micropterus coosae was most sensitive to frequencies that
overlap with the peak frequencies of their vocalizations, and the vocalizations
of a prey species, Cyprinella trichroistia. Bass hearing sensitivities at lower
frequencies, measured in terms of particle acceleration, were similar to
several sciaenid species.
For reprints please contact D. E. Holt (email:
Dr. Sonja Amoser