Early life history traits and geographical distribution of Parachaenichthys charcoti

Antarctic science

Mario La Mesa¹  Emilio Riginella²  Christopher D. Jones³ 

[1] 1ISMAR-CNR, Istituto di Scienze Marine, UOS Ancona, Largo Fiera della Pesca, 60125 Ancona, Italy;2Dipartimento di Biologia, Università di Padova, Via U. Bassi 58/B, 35131 Padova, Italy;3Southwest Fisheries Science Center, National Marine Fisheries Service, NOAA, 8901 La Jolla Shores Drive, La Jolla, CA 92037, USA

关键词: age and growth;    Antarctic Peninsula;    bathydraconid;    juveniles;    larvae;    zoogeography;   

DOI  :  10.1017/S0954102017000189

学科分类：自然科学（综合）

来源: Cambridge University Press

【 摘 要 】

The geographical distribution of the two species of the genus Parachaenichthys is allopatric and restricted to the inner shelves of South Georgia–South Sandwich Islands (P. georgianus) and South Orkney Islands–South Shetland Islands (P. charcoti). To evaluate the consistency between the geographical patterns of adult distribution and early life history traits of P. charcoti, sagittal otoliths were used to estimate growth rate and pelagic duration in larvae and juveniles of this species collected in the Bransfield Strait in winter and summer, respectively. Individual age was determined through microincrement counts, assuming they were daily increments. The Gompertz model was fitted to age–length estimates, providing a mean growth rate of 0.22 mm day-1 estimated for 28–204-day-old individuals. Larval hatching was spread over a relatively wide period, lasting from July throughout September. The pelagic larval duration of P. charcoti was about six months based on ageing data of larvae and juveniles, as reported for P. georgianus from South Georgia. The strong dependence of larvae on the inshore habitat may hamper their dispersal at large spatial scale limiting the connectivity among distant populations, providing clues to interpret the present geographical distribution of the two species.

【 授权许可】

CC BY