Modeling the egg and larval transport pathways of the Antarctic toothfish (Dissostichus mawsoni) in the East Antarctic region: New insights into successful transport connections

• Published in: Fisheries Oceanography
• Main Authors: Mori Mao, Mizobata Kohei, Ichii Taro, Ziegler Philippe, Okuda Takehiro
• Format: Article in Journal/Newspaper
• Language: English
• Published: John Wiley & Sons Ltd 2021
• Subjects: Antarctic toothfish (Dissostichus mawsoni); coastal recirculation; East Antarctic region; egg and larval transport; fish life history; Lagrangian particle tracking; satellite-derived velocity; トッテン棚氷融解の引き金：海洋渦が介在する沖合から棚氷への熱輸送過程の解明; Triggering of Totten Shelf Melting: Elucidation of Heat Transport Process from offshore to Ice Shelf mediated by Oceanic Eddy; 東南極トッテン棚氷へ暖水を運ぶ巨大な定在海洋渦の成因と循環流量の変動要因の解明; Elucidation of the formation mechanisms of the large standing oceanic eddy and the factors controlling eddy circulation contributing to warm water transport to the Totten Ice Shelf in East Antarctica; Antarctic; Banzare Bank; East Antarctica; Kerguelen; Southern Ocean; The Antarctic; Antarc*; Antarctic Toothfish; Antarctica; Ice Shelf; Sea ice; Totten Ice Shelf
• Online Access: https://oacis.repo.nii.ac.jp/?action=repository_uri&item_id=2337; http://id.nii.ac.jp/1342/00002279/

The Antarctic toothfish (Dissostichus mawsoni) is an important fishery species widely distributed in the Southern Ocean, especially in areas covered by sea ice. Understanding fish distributions and life cycles, including the transport and survival of eggs and larvae, is essential for the assessment and sustainable management of the fishery. However, owing to difficulties with in situ winter observations, information on the early life stages of D. mawsoni is lacking. Here, we investigated the transport pathways of fish eggs and larvae through a particle tracking study, using satellite-derived ocean surface velocities in the East Antarctic region, which includes important D. mawsoni habitats and exploratory fisheries. Our results indicate that particles released from continental slopes are more likely to be successfully transported to suitable settlement grounds than those released from the BANZARE Bank (the southern region of the Kerguelen Plateau), which is situated further north and has been hypothesized to be a potential spawning ground for D. mawsoni. This study demonstrates successful source–settlement connections in relation to ocean recirculation and suggests important settlement regions for D. mawsoni larvae in the East Antarctic region.