Spat production of the great scallop (Pecten maximus): a roller coaster¹This review is part of a virtual symposium on current topics in aquaculture of marine fish and shellfish.

Abstract

The great scallop (Pecten maximus (L., 1758)) has been of interest for aquaculture in Europe since the early 1970s. Since then, a large part of the research and development has focussed on reproduction and early life stages to support hatchery production of spat. Results from the last two decades show that production stability is lacking and have followed a roller-coaster trend. Production strategy varies, but in general, broodstock are collected from the wild and conditioned to gonad maturity sufficient for successful spawning. Natural reproduction cycle varies between populations, which is a challenge to hatcheries aiming at stable year-round production. Larval survival was for many years dependent on addition of antibiotics until a flow-through culture was established, and seasonal variation may be caused by variation in gamete or seawater quality. Settlement, metamorphosis, and spat growth depend on healthy larvae and appropriate culture environment. For efficient spat production, the use of land-based nurseries is promising. Results show that mean yield of spat from eggs is less than 1%. The review concludes that the gap between results obtained in hatchery production and in experiments shows a great potential for production increase.Résumé : L'aquaculture européenne s'intéresse au grand pétoncle (Pecten maximus (L., 1758)) depuis le début des années 1970. Depuis lors, une partie importante de la recherche et du développement s'est concentrée sur la reproduction et les premiers stades de vie afin de favoriser la production de naissains en culture. Les résultats des deux dernières décennies montrent qu'il manque une stabilité dans la production et que les tendances ressemblent à des montagnes russes. Les stratégies de production varient, mais généralement le stock reproducteur est récolté en nature et conditionné jusqu'à la maturité des gonades pour obtenir une fraie réussie. Le cycle de reproduction naturelle varie d'une population à l'autre, ce qui présente un défi pour les cultures qui visent une production stable à l'année. La survie des larves a dépendu pendant de nombreuses années de l'addition d'antibiotiques jusqu'à qu'on mette au point une culture avec système de circulation; la variation saisonnière peut être due à la variation dans la qualité des gamètes ou de l'eau de mer. La fixation, la métamorphose et la croissance du naissain dépendent de la santé des larves et de la présence d'un milieu approprié de culture. Pour une production efficace du naissain, l'utilisation de nourriceries en milieu terrestre est prometteuse. Les résultats indiquent que le rendement moyen du naissain à partir des oeufs est de moins de 1 %. Notre rétrospective conclut que l'écart entre les résultats obtenus par aquaculture et en laboratoire montre qu'il existe un fort potentiel pour l'accroissement de la production.[Traduit par la Rédaction]

Effect of increased <i>p</i>CO<sub>2</sub> level on early shell development in great scallop (<i>Pecten maximus</i> Lamarck) larvae

“…Local broodstock were collected in January 2012 from the outer Hardangerfjorden, located on the south-western coast of Norway. Ten scallops were conditioned for eight weeks at 12.0-12.5 • C and fed 13-15 cells µL −1 of a standard diet containing Isochrysis galbana (Tahitian), Pavlova lutheri and Chaetoceros mulleri (Andersen et al, 2011). Spawning was induced on 21 March by increasing the temperature to 16-17 • C. Pecten maximus is a simultaneous hermaphrodite, and some sperm will remain in the genital tract, resulting in self-fertilization (Mackie, 1984).…”

“…The great scallop is a highly valued sea food product, and has been cultured for more than 25 yr in Norway. The extended research efforts during the same period make it an excellent candidate for OA studies (Andersen et al, 2011). To our knowledge, only the study of Schalkhausser et al (2012) has shown the effect of OA on P. maximus.…”

Understanding the mechanisms involved in the high sensitivity of Pecten maximus larvae to aeration

“…The great scallop, Pecten maximus (Linnaeus, 1758), is a native European bivalve mollusc that lives on the Eastern Atlantic coast between Norway and Spain. P. maximus is a species of great commercial importance, whose meat is highly valued and sought after in the European seafood market (Andersen et al 2011). Compared with wild fisheries, which account for 55 501 tons of harvested scallops, its aquaculture production is relatively small (79 tons in 2015; FAO, 2015) and occurs only in France, Ireland, and Norway.…”

“…Compared with wild fisheries, which account for 55 501 tons of harvested scallops, its aquaculture production is relatively small (79 tons in 2015; FAO, 2015) and occurs only in France, Ireland, and Norway. These data largely underestimate the role of scallop aquaculture production, as most hatchery-produced seed is used for restocking natural populations to benefit scallop fisheries (Andersen et al 2011). To date, hatchery practices have been limited by difficulties mainly related to the larval rearing stages.…”

“…To date, hatchery practices have been limited by difficulties mainly related to the larval rearing stages. Despite recent progress in the development of new culturing techniques (Andersen et al 2011;Holbach et al 2015;Kesarcodi-Watson et al 2016), great scallop hatchery production is still unpredictable due to the large variations in larval survival. Therefore, to overcome this hurdle, further research is needed.…”