Summary The Quebec region of the Department of Fisheries and Oceans (DFO) is responsible for the assessment of several fish and invertebrate stocks exploited in the Estuary and the northern Gulf of St. Lawrence. The commercial catches sampling program is one of the sources of information used to complete these assessments. The data collected by this program, at wharf or at sea, offers among other things the advantage of a relatively large spatio-temporal coverage and provides some of the necessary knowledge to assess the demography and the structure of the exploited populations. This program is implemented by specialized DFO staff whose main mandate is to collect biological data on groundfish, pelagic fish and marine invertebrate species that are commercially exploited in the various marine communities. Data This dataset on the American lobster (Homarus americanus) includes the metadata, sample weight, cephalothorax length, sex and the number of specimens measured. This dataset covers the periods of 1998 and 2000 to present. In order to protect the confidentiality of the sources, some informations (such as those concerning the vessel) have been excluded and others (such as the date of capture) have been simplified. Entries where there was only one vessel in a fishing area for a given year were also excluded. Further information including the fishing areas coordinates can be found by clicking on the «Atlantic and Arctic commercial fisheries» and «Fishing areas» links below.

Total number of transects surveyed and total number of lobsters measured for each site in each year. There are some sites that do not have any coordinates identified, therefore these have not been included in the Web Map Services (WMS).

The lobster recruitment project is run by the Fishermen and Scientist Research Society (FSRS) through DFO funding. Fishermen participating in the lobster recruitment project collect information about lobster in their fishing area by fishing 2-5 scientific project traps (SPTs) (fished in fixed locations) within the regular commercial season. The SPTs used in all fishing areas are smaller than commercial traps and designed to primarily catch juvenile lobsters below the legal-size limit. These traps are additional to the vessel's legal number of commercial traps. The lobster recruitment project has more than 120 fishers participating from all LFAs along the Atlantic coast of Nova Scotia from LFA 27 in Cape Breton to LFA 35 in the Bay of Fundy (excluding LFA 28, who have not participated to-date). The number of fishermen per LFA and number of SPTs per fisherman are decided on by the LFA Advisory Committees. This decision considers how much additional effort they were comfortable having in the LFA (i.e. number of SPTs) and from how many traps each fisher could be reasonably expected to collect data. It is also important to have fishers dispersed enough to maximize study footprint. DFO Science consults on project design. SAMPLING METHODS: The fishers record the number, sex and length of lobsters captured in each SPT, as well as presence of eggs, tags or v-notch. Bottom temperatures are monitored by placing a temperature recorder in one of their SPTs for the entire lobster season. Cite this data as: Tibbets-Scott, S., Zisserson, B. Data of: Fishermen and Scientist Research Society (FSRS) Lobster Recruitment Trap Project. Published: November 2020. Population Ecology Division, Fisheries and Oceans Canada, Dartmouth, N.S. https://open.canada.ca/data/en/dataset/a88f9b4d-b59a-44f6-ae7e-d36550266940

PURPOSE: The primary objective of this survey is to obtain an index of the abundance of American lobster (Homarus Americanus) in the Northumberland Strait. This research survey also provides fisheries-independent information for all of the species captured by the trawl. DESCRIPTION: Catch weight, length frequencies, and biological information for crustaceans and fish caught during the annual July-August research vessel trawl survey in Northumberland Strait (NAFO Division 4T). Abundance indices and spatial distribution patterns of commercial and non-commercial crustaceans and other groundfish. PARAMETERS COLLECTED: The full catch is sorted to species, or lowest taxonomic group possible, and weighed. For lobster, carapace length, sex and carapace condition (i.e. stage of moult) are recorded. For female lobster, the presence or absence of eggs is noted and, starting in 2010, the stage of development of the eggs (i.e. new or old) when present was also recorded. Similarly, for crabs, the carapace width, sex and carapace condition (i.e. stage of moult) is recorded as is the presence or absence of eggs (for females). Fish sampling varied over the years but, starting in 2005, length has been recorded for all fish captured. For large catches, the complete catch is sorted and weighed, but sub-sampling, by species, is used for the other measurements. NOTES ON QUALITY CONTROL: Data are checked for irregularities. SAMPLING METHODS: The Northumberland Strait multi-species survey began in 2001 as a random stratified survey and now employs a random selection of sampling sites within the study area. Sampling is completed annually over a 4-week period in July and August. 110 stations are sampled in Northumberland Strait in water depths exceeding 4 m at Lowest Normal Tide. The survey has employed a 286 rockhopper trawl in all years from 2001 to 2018, except in 2010 and 2011 when a Nephrops trawl was used. In 2019, a newly designed trawl (termed the “Northumberland trawl”) was used in addition to the rockhopper trawl. The Northumberland trawl is similar to the rockhopper trawl but with a smaller footgear and smaller mesh sizes. At each station, the trawl is towed for a set period of time (recently 15 minutes with the rockhopper trawl and 10 minutes with the Northumberland trawl). USE LIMITATION: Please contact the data custodians before attempting to use this information in support of any kind of scientific analyses.