Distribution pattern of larval fish populations in the Northwestern Mediterranean

Abstract

Spatiotemporal distribution patterns in the larval fish community were studied off the Catalan coast (NW Mediterranean) between April and October 1983. Important seasonal variations in species composition were detected. The causes of this temporal heterogeneity lay in the species richness of the area and the spawning periods of adults. Spatial heterogeneity depended on the combined effects of topography and hydrographic features of the reglon. The existence of a shelf-slope front along the shelf break was one of the most important factors and was associated with maximum larval abundance. The current running along the coast from north to south together with the diversity of bottom structure and type also made major contributions to spatial heterogeneity. Four distinct geographical zones coinciding with bottom features were differentiated by statistical analysis. The species groups defining these 4 zones largely coincided with habitat and behaviour of the adults. However, with the diversity of features of the regon, the species were not limited solely to a single assemblage, giving rise to a gradation rather than to well-defined associations.

Temporal patterns of larval fish distribution and abundance in a coastal area of northern Greece

“…The anchovy has been reported to be the dominant species in terms of larval abundance during the summer in other areas of the Greek seas (Sorra et al, 2000). The high abundance of anchovy larvae, which has also been reported for the northwestern Mediterranean off the Catalan coast (Sabatés, 1990), is probably attributed to the preference of the species to spawn in areas influenced by freshwater input (Palomera, 1992;Tudela and Palomera, 1997). The concentration of European anchovy larvae in the outer parts of the Strymonikos Gulf during May 1998 is probably due to the beginning of the spawning in the outer parts of the gulf (Palomera and Sabates, 1990).…”

“…Studies in other Greek marine areas include ninety taxa for Pagasitikos Gulf (central Aegean) (Caragitsou et al, 2001) and sixty-six for Kissamos Gulf (NW Crete) (Papasissi, 1998). Comparison with other Mediterranean studies revealed that most (55.6%) of the larval fish taxa found by Sabatés (1990) off the Catalan coast were also present in the Strymonikos Gulf. Similarly, 54.5% of the taxa recorded by Palomera and Olivar (1996) a nearshore NW Mediterranean area were also present in the Strymonikos Gulf.…”

“…Moser and Smith, 1993). In the Mediterranean, larval fish assemblage studies have been carried out in the northwestern Mediterranean (Sabatés, 1990;Palomera and Olivar, 1996;Sabatés and Olivar, 1996;Olivar and Sabatés, 1997), paying particular attention to commercial small pelagic fish larvae (Palomera 1992;Palomera and Sabatés, 1990;Garcia and Palomera, 1996). Ichthyoplankton data on the eastern Mediterranean, especially on a seasonal basis, are limited.…”

Larval fish distribution in shallow coastal waters off North Western Iberia (NE Atlantic)

“…Environmental factors, such as salinity and temperature, have been shown to play an important role in the occurrence, density and growth of the larval stages of fishes (Rakocinski et al, 1996;Esteves et al, 2000). Sabatés (1990) highlights the importance of seasonality in larval fishes community structure. Palomera and Olivar (1996) also outline the importance of seasonality in the coastal zone, which is reflected in a high number of species during the spring and summer months but higher total larval abundance peaks in winter (which is attributed to the autumn and early winter spawners) (this was particularly so for Ammodytes tobianus larvae which were particularly abundant in the late winter early spring month of March).…”

The influence of oceanographic fronts and early-life-history traits on connectivity among littoral fish species

“…some species may spawn benthic eggs from which pelagic larvae hatch, other species may display life cycles where both the eggs and the larvae are pelagic, whereas other species may have evolved peculiar forms of parental care such as the use of brood pouches, mouthbrooding, or bearing live young (28,29). Also, the pelagic larval duration (PLD) as well as the spatial distribution of pelagic stages (i.e., inshore-offshore) also shows great variability among marine species (30)(31)(32)(33)(34). Under this scenario, it is expected that species with extended pelagic phases and offshore distributed larvae would be more apt to disperse over greater distances that species with shorter (or no) pelagic phase and inshore distribution (35).…”