title: Could ocean currents be responsible for the west to east spread of aquatic invasive species in Maritime Canadian waters?
abstract: The circulation in the shelf seas of Maritime Canada is predominantly in the northeast-southwest direction. Despite the mean northeast-southwest flow, a number of AIS invasions have been observed to proceed in the opposite direction - from the Gulf of Maine, around Nova Scotia, and into the southern Gulf of St. Lawrence. Flow fields from a numerical circulation model are used to investigate whether these invasions could be due to drift in ocean currents. Particle tracking experiments are performed and probability density functions (PDFs) derived that describe the probability of drifting a given upstream distance in a given drift time. Analysis of these PDFs revealed that for invasions that took 20-40 y to occur, propagule drift in ocean currents could be responsible for the upstream spread, while this was not the case for short timescale invasions (<10 y). Rafting could be responsible for both short and long timescale invasions.
authors.affiliation: Fisheries and Oceans Canada, Bedford Institute of Oceanography, P.O. Box 1006, Dartmouth, NS, B2Y 4A2, Canada. Electronic address: David.Brickman@dfo-mpo.gc.ca.
authors.forename: D
authors.initials: D
authors.lastname: Brickman
mesh_terms: D000465:Algorithms; D063147:Animal Distribution; D000818:Animals; D003386:Brachyura / Q000502:physiology*; D005843:Geography; D058865:Introduced Species; D007814:Larva / Q000502:physiology; D008281:Maine; D008962:Models, Theoretical; D009674:Nova Scotia; D009792:Oceans and Seas; D012044:Regression Analysis; D014872:Water Movements
keywords: AIS spread; Egg larval drift; Ocean currents; Rafting