National Survey of Sea Lice (Lepeophtheirus salmonis Krøyer and Caligus elongatus Nordmann) on Fish Farms in Ireland – 2019

• Main Authors: O’Donohoe, P., Kane, F., Kelly, Suzanne, D'Arcy, J., Casserly, Joanne, Downes, Jamie K., McLoughlin, S., Ruane, N.M., Jackson, D.
• Format: Report
• Language: English
• Published: Marine Institute 2020
• Subjects: sea lice monitoring; Sea lice; Fish health; Fish farms; Salmonid; Caligus elongatus Nordmann; Lepeophtheirus salmonis Krøyer; Atlantic salmon
• Online Access: http://hdl.handle.net/10793/1590

Farmed stocks of Atlantic salmon in Ireland are inspected on 14 occasions throughout the year to monitor sea lice levels as part of a national programme. Sea lice are a naturally occurring parasite found on marine fish, including salmonids. They are small ecto-parasitic copepod crustaceans and there are approximately 559 species. The objectives of the National Sea Lice Monitoring Programme are:  To provide an objective measurement of infestation levels on farms.  To investigate the nature of infestations.  To provide management information to drive the implementation of control and management strategies.  To facilitate further development and refinement of this strategy. The sea lice control and management strategy has five principal components:  Separation of generations.  Annual fallowing of sites.  Early harvest of two-sea-winter fish.  Targeted treatment regimes, including synchronous treatments.  Agreed husbandry practices.