Management of Sea Lice in B.C.

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In B.C., Fisheries and Oceans Canada is the lead federal agency for aquaculture and is responsible for ensuring that the aquaculture industry operates in a sustainable manner. Sea lice management is of the utmost interest and levels are strictly monitored and managed to ensure the continued health and safety of the coastal ecosystem.

Under the B.C. Aquaculture Regulatory Program, the Department manages:

• Mandatory monthly sea lice monitoring and documentation, including individual salmon observations, by both industry and Fisheries and Oceans Canada fish health staff. 
• The implementation of a Fish Health Management Plan (FHMP) as a condition of licence for all salmon farming companies.
• Sea lice audits of salmon farms conducted by Fisheries and Oceans Canada and reported quarterly¹. The number of farms selected for audit is increased during the wild smolt out-migration period (March through June).
• Information collected on sea lice abundance from salmon farms, which is evaluated with environmental information and supports integrated area management of sea lice populations during wild stock out-migration.

Detailed results of industry sea lice counts are available at: http://www.pac.dfo-mpo.gc.ca/aquaculture/reporting-rapports/lice-pou-eng.htm

Fisheries and Oceans Canada’s Science branch also supports sea lice management by conducting aquaculture-specific research, monitoring wild salmon stocks and sea lice outside of salmon farm net pens and enforcing regulations relating to aquatic animal health.

All farmers of Atlantic salmon are required to monitor the abundance of sea lice on their farms at least once a month. At any given time, should the average motile lice per fish reach three, definite and rapid action must be taken. Since recent assessments of Pacific salmon farms indicate that few if any lice are found on farmed chinook and coho salmon, the monthly monitoring requirements continue to apply only to Atlantic salmon farms. Sea lice reduction actions may include:

• increased frequency of monitoring;
• harvesting of most affected populations, therefore reducing the numbers of lice at the farm;
• use of therapeutants to treat lice infestation; and/or
• applying other farm husbandry techniques to reduce the abundance of lice.

Sea Lice Management in British Columbia and the World

Of the numerous countries that farm Atlantic salmon, British Columbia has some of the most strictly managed sea lice regulations and monitoring programs.

Comparison of Action Levels in Other Countries (from the 2009 B.C. Ministry of Agriculture and Land’s Annual Fish HealthReport)

Country	Time of Year	Trigger Level	Action(s)
Norway	Year round	0.5 adult females 3 motile lice	Various treatments are available
Scotland	Spring time Remainder of year	No official trigger but targets are: 0.5 adult females 1 adult female	Various treatments are available
Ireland	March 1 – April 30	0.3 – 0.5 egg-producing (gravid) females per fish	Various treatments are available
	May 1 – February 28	2 gravid females per fish
Chile	Year round	6 motile lice per fish	Various treatments are available
B.C. Canada	March 1 – June 30	3 motile lice per fish* 3 motile lice per fish	Harvest or treat (1 in-feed drug available)
	July 1 – February 28		Elevate monitoring, or apply treatment, or  harvest

* An analysis of B.C. Ministry of Agriculture and Lands data (of second quarters 2006 - 2009 during the fry out-migration period) indicates that an abundance of zero to three motile lice per fish includes fewer than 0.3 gravid females per fish in that same season, March to July. This low abundance of gravid females in B.C. remains lower than trigger values assigned in other countries.