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).

CITATION LIST:

Rondeau, A.; Comeau, M.; Surette, T.. 2014. Assessment of the American Lobster (Homarus americanus) Stock Status in the Southern Gulf of St. Lawrence (LFA 23, 24, 25, 26A and 26B). CSAS Research Document 2014/036.

Comeau, M., and Hanson, J.M.. 2018. American lobster: persistence in the face of high, size-selective, fishing mortality—a perspective from the southern Gulf of St. Lawrence. Canadian Journal of Fisheries and Aquatic Sciences 999: 1-11.

Bosman, S., Methven, D., Courtenay, S., and Hanson, J.. 2011. Fish assemblages in a north Atlantic coastal ecosystem: spatial patterns and environmental correlates.. Estuarine, Coastal and Shelf Science 92(2):232-245.

Hanson, J.M.. 2001. Pre-fishery abundance and distribution of American lobster in western Northumberland Strait, 1999 and 2000.. CSAS Research Document 2001/079.

Kelly, J., and Hanson, J.. 2013. Maturity, size at age and predator–prey relationships of winter skate Leucoraja ocellata in the southern Gulf of St Lawrence: potentially an undescribed endemic facing extirpation. Journal of Fish Biology 82(3): 959-978.

Rondeau, A., Hanson, J.M., Comeau, M., and Surette, T.. 2016. Identification and characterization of important areas based on fish and invertebrate species in the coastal waters of the southern Gulf of St. Lawrence.. CSAS Research Document 2016/044.

Voutier, J.L., and Hanson, J.M. 2008.. 2008. Distribution, abundance, and feeding of a disjunct population of lady crab in the southern Gulf of St. Lawrence, Canada. Aquatic Ecology 42(1): 43-60.