Egg and larval distributions of seven fish species in north‐east Atlantic waters

Abstract

The distribution of egg and larvae of mackerel, horse mackerel, sardine, hake, megrim, blue whiting and anchovy along the European Atlantic waters (south Portugal to Scotland) during 1998 is described. Time of the year, sea surface temperature and bottom depth are used to define the spawning habitat of the different species. Mackerel, horse mackerel, and sardine eggs and larvae presented the widest distribution, whereas megrim and anchovy showed a limited distribution, restricted to the Celtic Sea and the Bay of Biscay respectively. Correspondingly mackerel, horse mackerel and sardine showed the highest aggregation indices. Blue whiting larvae were found at the lowest temperatures, whereas anchovy eggs and larvae were found in the warmest waters. The analysis is a basis for evaluation of ongoing changes in the pelagic ecosystem of the north-east Atlantic.

Spatio-temporal distribution and biomass of Benthosema pterotum (Pisces: Myctophidae) in the shelf region of the East China Sea

“…Quotient analyses (Ibaibarriaga et al 2007, Neira & Keane 2008 were performed on data of Benthosema pterotum densities (ind. km -2 ) across all 5 surveys combined to describe selection of habitat in terms of bottom depth (m), temperature (°C), and salinity in the bottom layer.…”

Internal tidal mixing as a control on continental margin ecosystems

“…Vessels target spawning stocks of mackerel, horse mackerel, hake, blue whitting and anchovies (Reid, 2001;ICES, 2007). Based on the distribution of eggs and larvae, the spawning habitat of these species is very tightly associated with the 200 metre isobath at the shelf edge (Ibaibarriaga et al, 2007). High fish concentrations along continental margins are often explained in terms of a nutrient supply fuelling enhanced primary production, supporting high densities of physicallyaggregated zooplankton, ultimately providing more food for fish (Genin, 2004).…”

Abundance patterns of early stages of the Pacific sardine (<i>Sardinops sagax</i>) during a cooling period in a coastal lagoon south of the California Current

“…Early stages of small pelagic fishes display latitudiarly stages of small pelagic fishes display latitudinal differences separated by preferential SST intervals in different ecosystems around the world (Parrish et al 1989, Lluch et al 1991, Coombs et al 2006, Ibaibarriaga et al 2007). In the northeast Pacific, spawning of the Pacific sardine, Sardinops sagax, occurs over a wide SST range (13-25°C) across the area of influence of the California Current and Gulf of California.…”

“…The spawning season was characterized in terms of the explanatory variables recorded by means of quotient analysis. This technique is commonly used to identify preference or avoidance of spawning zones by assessing the distribution of eggs and larvae in relation to covariates of interest (Emmet et al 2005, Ibaibarriaga et al 2007. A canonical corre-A canonical correspondence analysis (CCA) was applied to correlate egg and larval abundance with environmental variables.…”

“…The spatial range and location of spawning can be critical for eggs and larvae due to interan-nual changes in population structure and geographic variations in environmental conditions (Planque et al 2007, Smith and Moser 2003, Emmett et al 2005, Ibaibarriaga et al 2007, Coombs et al 2006. However, few comprehensive surveys of eggs and larvae are available to determine preferred spawning locations and little is known of the stock structures of various important species (Agostini and Bakun 2002), which are influenced by physical processes that provide favourable habitat requirements for larval growth and survival (Lasker 1978, Parrish et al 1981, Bakun 1996, Logerwell and Smith 2001, Lynn 2003, McClatchie et al 2007, Planque et al 2007, Aceves-Medina et al 2009).…”