Research Document - 2016/004
Preliminary results from the groundfish and shrimp multidisciplinary survey in August 2015 in the Estuary and northern Gulf of St. Lawrence
By Hugo Bourdages, Claude Brassard, Mathieu Desgagnés, Peter Galbraith, Johanne Gauthier, Benoît Légaré, Claude Nozères, Eric Parent and Philippe Schwab
The Department of Fisheries and Oceans conducts an annual multidisciplinary survey in the Estuary and northern Gulf of St. Lawrence. The objectives of this survey are quite varied: assess the biodiversity of the species near the floor, estimate the abundance of groundfish and invertebrates, assess physical and biological oceanographic conditions (phytoplankton and zooplankton), monitor the pelagic ecosystem, take an inventory of marine mammal and seabird, and collect samples for various research projects. In 2015, the survey was conducted between August 1 and September 2 on board the CCGS Teleost. During this survey, 190 trawl tows were successful as well as 133 CTD casts of the water column and 91 zooplankton samples.
This report presents the results from catches from the 190 tows. In total, 84 fish taxa and 196 invertebrate taxa were identified during the mission. Historical perspectives (catch rates, spatial distribution and length frequency) are presented for about 20 taxa. These commercial fishery-independent data will be used in several stock assessments (e.g., cod, redfish, Greenland Halibut, Atlantic Halibut and Northern Shrimp). For these species, abundance and biomass indicators in 2015 are comparable to the average or show upward trends, especially for small redfish.
Preliminary data analysis for water temperature measured in 2015 shows very hot conditions in deep water (150 m and more), but near normal condition for the cold intermediate layer and the summer surface water.
- Date modified: