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For the past 6 days, I have been quite fortunate to experience my first offshore cruise in the Northwest Atlantic Ocean aboard the CCGS M. Perley – a Canadian Coast Guard research vessel. This is not my first time away from land – I’ve conducted research from fishing vessels in the Bay of Fundy and from zodiac in the Bras d’Or lakes. Even as a kid growing up in a small fishing community I was exposed to the sea, frequenting fishing vessels owned by friends’ parents. However, this was my first time venturing a substantial distance offshore on a large research vessel to sample the benthic diversity associated with the NW Atlantic.
As a recently hired biologist at Fisheries and Oceans Canada in Moncton, New Brunswick, I was offered the chance to assist in an annual (but temporary) scallop survey off the northern coast of New Brunswick. The five-year-long survey has been established since 2012, with this year being the last year of the survey. A bottom trawl is used to collect benthic samples. We trawled for 2 minutes at each site and organisms brought up were sorted, identified, counted, weighed, and measured on deck in between drags. This made for intensive 12 hour days, but the data alone provided enough currency and motivation to keep me going.
While the cruises are dedicated to assessing scallop populations off the coast of New Brunswick, data on a slew of other benthic species are collected. Indeed abundances and biomass of all collected species are recorded, along with other basic morphometrics of other key species (e.g. carapace morphometry of crabs and lobsters, and lengths of fishes). We also had a CTD on board, equipped with probes to measure depth, conductivity, temperature, salinity, dissolved oxygen, and pH.
The experience was nothing short of spectacular. I’ve come to note that sunrises and sunsets are much more appealing from sea. The diversity of animals was astounding and unpredictable from trawl to trawl – crustacaens, cnidarians, echinoderms, molluscs, poriferans, and fishes were all apparent in multiple trawls. The most common species were crustaceans. Shrimps (Argis dentata, Pandalus borealis, Pandalus montagui, and Sclerocrangon borea) and rock crabs (Cancer irroratus) really dominated the trawls.
Closer to shore, lobsters (Homarus americanus) were quite abundant as well, while an abundance of snow crabs (Chionoecetes opilio) and toad crabs (Hyas araneus and Hyas coaractatus) were frequent at more offshore sites – in one trawl we hauled up >80 snow crabs! We also recorded quite a few Acadian hermit crabs (Pagurus acadianus).
In some of the trawls, a vast array of other species were evident. Echinoderms were also abundant. Sea cukes (Cucumaria frondosa, Psolus fabricii), urchins (Strongylo- centrotus droebachiensis), sand dollars (Echinarachinus parma), sea stars (Asterias spp., Crossaster papposus, Henricia sanguinolenta, Leptasterias polaris, Solaster end- eca), and brittle stars (Ophiopholis aculeata) were quite abundant in many trawls – we even saw a couple of large basket stars (Gorgonocephalus arcticus)!
A number of bivalves were also present, including clams (Arctica islandica, Cyclocardia borealis, Cyrtodaria silique, Mactromeris polynyma, Serripes groenlandicus, and Yolida sp.,), scallops (Chlamys islandica, Placopectin magellanicus), and horse mussels (Modiolus modiolus). Similarly to bivalves, brachiopods were abundant at a number of sites. We also observed a number of gastropods (Buccinum undatum, Neptunea decemcostata, Colus stimpsoni, Aporrhais occidentalis, Lunatia heros) and chitons were abundant at a number of stations. Less common were sponges, jellyfishes, and sponges. Tube worms (Polychaeata) dominated the deeper muddy zones (>50 m depth).
Fishes were also present in a number of trawls. Species observed included American plaice (Hippoglossoides platessoides), Arctic alligatorfish (Ulcina olrikii), Atlantic poacher (Leptagonus decagonus), cunner (Tautogolabrus adspersus), fourline snakeblenny (Eumesogrammus praecisus), yellowtail flounder (Limanda ferruginea), winter flounder (Pseudopleuronectes americanus), longhorn sculpin (Myoxocephalus octodecemspinosus) shorthorn sculpin (Myoxocephalus scorpius), grubby (Myoxocephalus aenaeus), lumpfish (Cyclopterus lumpus), ocean pout (Zoarces americanus), sea raven (Hemitripterus americanus), and sand lance (Ammodytes sp.)
Of course other species have been observed on trawls that I have not attended. The above list is nowhere near exhaustive, but is an overview of the species that I observed during my time on the M. Perley. The experience was fantastic, and I look forward to the next opportunity to get back to a place with a flat horizon.
Until then, it’s back to manuscripts and grant proposals…