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Acero,
P., William J. Richards, Felipe Amaya and María M. Criales: First Caribbean
record of Akko dionaea (Pisces: Gobiidae), another South American endemic , pp.
133-138
Akko
dionaea Birdsong
and Robins is reported here from the Colombian Caribbean, based on specimens
collected at the mouth of the estuary Ciénaga Grande de Santa Marta. Ten night
collections with channel nets at the mouth of the estuary yielded a total of
228 specimens representing larval to juvenile
stages. Specimens were captured during the new and full moon, mainly during the
dry season. Larval and juvenile stages of A. dionaea are described here for the first
time. The species undergoes strong
allometric changes during its development, mainly in
the length of the head and eye.
The species is described and the ecology and biogeography of the species are
discussed.
Alexei
M. Orlov: Bottom trawl-caught fishes and some features of their vertical
distribution in the Pacific waters off the north Kuril Islands and south-east
Kamchatka, 1993-1999, pp. 139-160
The
species composition of demersal fishes in Pacific waters off the north Kuril
Islands and south-east Kamchatka is considered. The study is based on 1275
demersal trawls carried out from 1993 to 1999 at depths between 76 and 833 m.
The
fishes identified in this study included 153 species, 97 genera, and 41
families; 62.1 % of the total were from the following families: snailfishes
(Liparidae); sculpins (Cottidae); righteye flounders (Pleuronectidae); skates
(Rajidae); eelpouts (Zoarcidae); rockfishes (Sebastidae) and poachers
(Agonidae). The relative abundances of the 153 species collected were
categorised as: Very rare: 79; Rare: 30; Common: 24; and Abundant: 20. Most
species found off the north Kuril Islands and south-east Kamchatka were also
common in the Sea of Okhotsk (74.5 %) and the western Bering Sea (80.4 %).
The
collected demersal fish species comprised: anadromous (1), neritic (3),
mesopelagic (26), middle shelf (18), outer shelf (18), mesobenthic (62), and
bathybenthic (25). Of the middle shelf species, the most abundant were northern
rock sole Lepidopsetta polyxystra and Atka mackerel Pleurogrammus monopterygius. Atka mackerel Pleurogrammus
monopterygius
was also the most abundant fish in the outer shelf group. The mesobenthic fish
fauna was dominated by the Alaska pollock Theragra chalcogramma, Pacific ocean perch Sebastes
alutus, Atka
mackerel Pleurogrammus monopterygius, and the northern rock sole, Lepidopsetta
polyxystra. The
most abundant bathybenthic fishes were the giant grenadier Albatrossia
pectoralis, popeye grenadier Coryphae-noides cinereus, broadbanded thornyhead Sebastolobus
macrochir, darkfin
sculpin Malacocottus zonurus, and dimdisc snailfish Elassodiscus tremebundus.
José Martins Silva-Jr, Flávio J. L. Silva and Ivan Sazima: Rest, nurture, sex, release, and play: diurnal underwater behaviour of the spinner dolphin at Fernando de Noronha Archipelago, SW Atlantic, pp. 161-176
At
Fernando de Noronha Archipelago in the South West Atlantic, spinner dolphins (Stenella
longirostris) regularly
congregate in large groups in a bay with clear, shallow water, allowing their
behaviour to be observed and recorded at close quarters. We present an overview
of the diurnal underwater activity of the Noronha spinners while in the bay.
Apart from well-known types of behaviour such as resting, mating, and playing, we
present and illustrate others such as suckling, defaecating, and vomiting which
are less well-known and documented. Heterospecific interactions and
associations are also discussed. An ecologically new role for cetaceans, as a
food supplier for reef fishes, is herein proposed for the Noronha spinners.
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