Ocean transport paths for the early life history stages of offshore-spawning flatfishes: a case study in the Gulf of Alaska Kevin M Bailey 1 , Alisa A Abookire 2 & Janet T Duffy-Anderson 1 1 Alaska Fisheries Science Center, 7600 Sand Point Way NE, Seattle, WA 98115, USA; 2 Alaska Fisheries Science Center, Kodiak Facility, 301 Research Court, Kodiak AK 99615 USA Abstract Offshore- and deepwater-spawning flatfish species face the problem of transport of their planktonic stages to shallow juvenile nursery grounds that are often far shoreward in bays or estuaries. We compare life history attributes of four offshore- spawning flatfish species in the Gulf of Alaska: Pacific halibut (Hippoglossus stenolepis), arrowtooth flounder (Atheresthes stomias), rex sole (Glyptocephalus zachirus) and Dover sole (Microstomus pacificus) to examine how their larvae get from a spawning location at the edge or beyond the continental shelf to specific inshore nursery zones. We utilize historical records of survey catches of different life stages to characterize the stage-specific changes in distribution of spawning, planktonic stages and juvenile nursery areas. We infer transport mechanisms based on the shifts in distribution of the life stages and in comparison with local physical oceanography. This comparison provides insight into the different mechanisms marine species may use to solve the common ‘problem’ of planktonic drift and juvenile settlement. Keywords Fish larvae, juvenile nursery, larval distribution, larval transport, ocean currents, spawning strategy Correspondence: Kevin M Bailey, Alaska Fisheries Science Center, 7600 Sand Point Way NE, Seattle, WA 98115, USA Tel.: +1 206 526 4243 Fax: +1 206 526 6723 E-mail: kevin. bailey@noaa.gov Received 24 May 2007 Accepted 6 Nov 2007 Introduction 45 Data 46 The Gulf of Alaska setting 47 Shelf features 47 Circulation 48 Life history attributes of offshore-spawning flatfishes 49 Spawning 49 Patterns in egg and larval distributions 55 Juvenile nurseries 56 Discussion of transport mechanisms 58 Spawning location and season 58 Transport onto the shelf 59 Transport along the shelf 60 Larval behaviours 62 Settlement and recruitment issues 62 Future studies 63 Acknowledgements 64 References 64 44 Ó 2008 The Authors Journal compilation Ó 2008 Blackwell Publishing Ltd F I S H and F I S H E R I E S , 2008, 9, 44–66