Satellite tagging of adult Patagonian toothfish (Dissostichus eleginoides) provides first evidence for unexpected movement patterns

To better understand Patagonian toothfish (Dissostichus eleginoides) movement and habitat in the Southwest Atlantic, fifty popup satellite archival tags (PSATs) were deployed off Davis Bank on North Scotia Ridge between 2019 and 2020 on adults ranging from 97-139 cm total length. PSATs (18 Lotek Wireless PSATFLEX and 32 Wildlife Computers MiniPAT) were programmed to detach after completing 1 to 16-month missions. Six tags failed to report, and among the remaining 44 reporting tags, 34 reported on schedule, up to 487 days at sea – the longest electronic tag deployment record for this species to date. Although the majority of PSATs reported within 50 km from the release sites, confirming high site fidelity, 12% of tags reported more than 200 km away, showing connectivity to South Georgia that has not previously been observed. A 1-month transit to the Falkland/Malvinas Plateau also revealed that toothfish can attain a surprisingly high movement rate of 33 km day^-1. Novel examples of toothfish movement capabilities, albeit a small sample size, are inviting us to broaden our examination on how adults move around their Scotia Arc habitats and link up different regional aggregation sites in the South Atlantic.