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Ichthyoplankton community of the Dardanelles Strait, Turkey

Daban İ. B., Yüksek A.

Oceanological and Hydrobiological Studies

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2017

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Vol. 46, No. 3

253--259

EN

An ichthyoplankton survey was conducted between March 2012 and February 2013 along the Anatolian coast of the Dardanelles Strait, with the aim of describing the species composition and temporal variation of fish eggs and larvae. For this purpose, monthly samples were collected at three sites using a WP-2 plankton net equipped with 500 µm mesh during a one-year period. Biodiversity indices were calculated to understand differences in biodiversity. A total of 50 teleost fish species belonging to 25 families and 7 orders were identified. The highest species richness of fish eggs was recorded in spring, whereas the highest species richness of fish larvae – in spring and summer. On the other hand, species richness of fish eggs and larvae were at a minimum in the fall. The most dominant species recorded in the Dardanelles were Sprattus sprattus as fish eggs and Engraulis encrasicolus as fish larvae. The relatively lower abundance of eggs and lack of earlier egg phases indicate that Engraulis encrasicolus does not spawn in the Dardanelles Strait, and the spawned eggs develop while drifting from the spawning grounds in the Marmara Sea to the sampling area.

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Spatial distribution and diet of larval snailfishes (Liparis fabricii, Liparis gibbus, Liparis tunicatus) in the Canadian Beaufort Sea

Walkusz W., Paulic J. E., Wong S., Kwaśniewski S., Papst M. H., Reist J. D.

Oceanologia

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2016

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No. 58 (2)

117--123

EN

This paper presents information on diet and distribution of larval snailfishes from the genus Liparis on the Canadian Beaufort Sea Shelf. In this study, 153 larval snailfishes of three species, Liparis fabricii, L. gibbus and L. tunicatus, were collected during 4 summer cruises (2003–2005, 2007). The majority of the larvae were either in flexion or post-flexion stage, and some were in pre-flexion stage. Liparis larvae appeared to be generalists in terms of diet and fed on a wide range of planktonic organisms. Pre-flexion larvae fed on small copepods (mainly adult stages of Triconia borealis). As larvae grew their diet shifted towards larger copepods (copepodids III/IV of Calanus hyperboreus, copepodids II–IV of Calanus glacialis and females of Metridia longa) and amphipods (Themisto libellula). Remarkably, larvaceans Oikopleura spp. and pelagic snails Limacina helicina made up a substantial part of the larval diet. This paper contributes to the knowledge on arctic larval fishes and to the ongoing efforts regarding Canadian Beaufort Sea ecosystem modeling.

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Composition of Trichiuridae and Gempylidae larvae (Teleostei) and their association with water masses in the Southwest Atlantic Ocean

Mafalda P. Jr., de Souza C.S., Weiss G.

Oceanological and Hydrobiological Studies

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2009

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Vol. 38, No.4

3-20

EN

In this paper the relationship between temporal changes in the occurrence of water masses and Trichiuridae and Gempylidae larvae composition and distribution in the Southwest Atlantic ocean were analysed between 25° and 40° S. Ichthyoplankton was collected during the three expeditions of the Subtropical Convergence Project: Winter and Spring 1977, Autumn 1978 and Summer 1981, realized in the Southwest Atlantic waters. Oblique tows were conducted using a Hensen net with 250 ěm mesh size. Steep salinity and temperature gradient were found, where the river outflows from La Plata river (Argentina) and Patos Lagoon (Brazil) met the Tropical Water over the continental shelf between 32 and 36° S. We examined 524 Hensen-net samples that contained about 283 larvae from five species of Trichiuridae and Gempylidae. The most abundant and frequent specie were Trichiurus lepturus Linnaeus 1758 and Diplospinus multistriatus Maul 1948. The mesopelagics species D. multistriatus, Nealotus tripes Johnson 1865 and Lepidopus altifrons Parin&Collette, 1993 were associated with Tropical Water. The benthopelagic T. lepturus and the epipelagic Thyrsitops lepidopoides (Cuvier 1832) were associated mainly with Coastal Water and Subtropical Shelf Water.