Rearing and production of European lobster ( Homarus gammarus ) larvae and postlarvae

• Main Authors: Lund, Ivar, Goncalves, Renata
• Format: Book
• Language: English
• Published: DTU Aqua 2023
• Subjects: European lobster; Homarus gammarus
• Online Access: https://orbit.dtu.dk/en/publications/4f234ff6-b98d-4802-b6b3-17cb08328d04; https://backend.orbit.dtu.dk/ws/files/333036795/426_2023_Rearing_and_production_of_European_lobster_larvae_and_postlarvae_1.pdf

Broodstock of European lobsters are usually obtained from the wild. Berried lobsters are typically caught during spring and summer or caught in autumn and kept overwintering until spawning. Berried females are kept separately to avoid fighting and to diminish possible stress and injuries. The fecundity is variable, between ca. 5000 and 40,000 eggs per female, with normal maturity attained between 80 and 140 mm carapace length. Breeders can be held at ambient temperature of water can be cooled or heated to promote slower or faster development of eggs. During development, the color of the eggs changes from greenish black to black to orange and eventually to dark red along with the embryos absorption and development. The eye index measurement can give a good indication of when larvae will hatch. Berried lobsters are typically disinfected before entering a hatchery to minimize risks of diseases. When in the system they are fed daily with mussles, shrimp or fish. Upon larvae hatching, they are removed and reared in separate incubators/ tanks and typically fed with krill, mysis or other planktonic feeds: Feeding with dry feeds or just simple overfeeding is prob- lematic and often leads to bacterial outbreaks, that can cause high mortalities. Live Artemia is typically a more secure option, as it will not organically pollute thus avoiding blooming and proliferation of bacteria. Improving hygiene ozone, UV and probiotics have been tested in lobster hatcheries as a sustainable, preventative strategy to reduce opportunistic infections, which may impact upon survival and growth. Compared to unozonated and un- UV controls, lobster larvae yielded poorer growth during the short pelagic period although they experienced reduced bacterial loading of larvae and culture water. Postlarvae (st IV) can be obtained within 8 days after hatching, but typically from around 12 days post hatching. Larvae are normally reared communally in tanks having a size of 50-120 L. After reaching the postlarvae stage the larvae are reared individually, ...