Four Decades of Ichthyoplankton Data for the Northern Gulf of St. Lawrence: An Analysis of the Communities over Time and Space

A database of ichthyoplankton data available for the northern Gulf of St. Lawrence (GSL), from the early 1970s to the present, is presented. The northern GSL is defined as the region extending north from the south margin of the deep Laurentian Channel. In contrast to the southern GSL, the region is characterized by narrow coastal shelves and two deep channels (Anticosti and Esquiman) branching from the Laurentian Channel in the east. Integrated over time and space the ichthyoplankton community counts 50 Species, under 46 Genera and 22 Families. For the analysis, the northern GSL is divided into four sub-regions, from west to east:  the Estuary, the northwestern gyre, the Anticosti Island, and the Esquiman Channel region.  On a presence-absence basis, excluding the middle Estuary where estuarine or freshwater taxa are found, all sub-regions present similar communities of marine species. Based on relative abundance however, Clupeidae (e.g., Clupea harengus),  Osmeridae (e.g., Mallotus villosus) and Ammodytes spp. largely dominate historically the western regions whereas Sebastes spp.  and Stichaeidae (4 species) dominate the Anticosti and Esquiman Channel regions.  Analyses are in progress to study the stability of these communities over time and to associate the communities and physical characteristics of the sub-regions.