Fecundity of the European lobster (Homarus gammarus) off southwestern Norway after stock enhancement: do cultured females produce as many eggs as wild females?

Published source details Agnalt A.-. (2008) Fecundity of the European lobster (Homarus gammarus) off southwestern Norway after stock enhancement: do cultured females produce as many eggs as wild females?. ICES Journal of Marine Science, 65, 164-170.
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This study is summarised as evidence for the following.

	Action	Category
	Transplant/release captive-bred or hatchery-reared species - Transplant/release crustaceans Action Link

Transplant/release captive-bred or hatchery-reared species - Transplant/release crustaceans

A controlled study in 1996–1997 in one seabed area off southwestern Norway, North Sea (Agnalt et al. 2008 - same experimental set up as Agnalt et al. 2007) found that when comparing individuals of similar sizes, female hatchery-reared European lobsters Homarus gammarus released into the wild carried similar numbers of eggs and their eggs were of similar weight, diameter, and developmental stage, compared to wild lobsters. For further details of results see graphs in paper. Between 1990 and 1994, hatchery-reared juvenile lobsters (approximately 128,000) were released as part of a restocking program. During autumn 1996, and spring and autumn 1997, egg-bearing female lobsters were collected from commercial landings. Hatchery-reared females (104 individuals) were differentiated from wild females (111 individuals) by the presence of tags. All female lobsters were measured (carapace length), and the weight of their egg mass recorded. For each female, egg count and size were assessed from subsamples. A note was made of any developing embryos.

(Summarised by: Anaëlle Lemasson & Laura Pettit)