A model for sea lice (Lepeophtheirus salmonis) dynamics in a seasonally changing environment.
Sea lice (Lepeophtheirus salmonis) are a significant source of monetary losses on salmon farms. Sea lice exhibit temperature-dependent development rates and salinity-dependent mortality, but to date no deterministic models have incorporated these seasonally varying factors. To understand how environmental variation and life history characteristics affect sea lice abundance, we derive a delay differential equation model and parameterize the model with environmental data from British Columbia and southern Newfoundland. We calculate the lifetime reproductive output for female sea lice maturing to adulthood at different times of the year and find differences in the timing of peak reproduction between the two regions. Using a sensitivity analysis, we find that sea lice abundance is more sensitive to variation in mean annual water temperature and mean annual salinity than to variation in life history parameters. Our results suggest that effective sea lice management requires consideration of site-specific temperature and salinity patterns and, in particular, that the optimal timing of production cycles and sea lice treatments might vary between regions.
Department of Biology, Memorial University of Newfoundland, St. John's, NL, Canada A1B 3X9. Electronic address: mar665@mun.ca.
Matthew A
MA
Rittenhouse
Centre for Veterinary Epidemiological Research, Department of Health Management, Atlantic Veterinary College, University of Prince Edward Island, 550 University Avenue, Charlottetown, PEI, Canada C1A 4P3. Electronic address: crevie@upei.ca.
Crawford W
CW
Revie
Department of Biology, Memorial University of Newfoundland, St. John's, NL, Canada A1B 3X9; Department of Mathematics and Statistics, Memorial University of Newfoundland, St. John's, NL, Canada A1C 5S7. Electronic address: ahurford@mun.ca.
Amy
A
Hurford
D000818:Animals; D001955:British Columbia; D033342:Copepoda; D005260:Female; D005393:Fish Diseases / Q000453:epidemiology*; D011157:Population Dynamics; D012474:Salmon; D012621:Seasons
Aquaculture; Delay differential equations; Mathematical model; Sea lice; Seasonality