FN Archimer Export Format PT J TI Changes in environmental salinity during the life of Pangasius krempfi in the Mekong Delta (Vietnam) estimated from otolith Sr : Ca ratios BT AF TRAN, Ngan T. LABONNE, Maylis HOANG, Huy D. PANFILI, Jacques AS 1:1;2:2;3:1;4:1,2; FF 1:;2:;3:;4:; C1 Vietnam Natl Univ Ho Chi Minh City, Univ Sci, 227 Nguyen Van Cu,Dist 5, Ho Chi Minh City, Vietnam. UM, Inst Francais Rech Exploitat Mer Ifremer, IRD, Marine Biodivers Exploitat & Conservat MARBEC,CNR, Cc093,Pl E Bataillion, F-34095 Montpellier, France. C2 UNIV HO CHI MINH, VIETNAM IRD, FRANCE UM MARBEC IN WOS Cotutelle UMR copubli-int-hors-europe copubli-sud IF 1.488 TC 15 UR https://archimer.ifremer.fr/doc/00598/70966/69194.pdf https://archimer.ifremer.fr/doc/00598/70966/69195.pdf LA English DT Article DE ;behaviour;climate change;diadromous fish;microchemistry;Pangasiidae AB Pangasius krempfi is a commercially important catfish in the Mekong River and is believed to migrate along the Mekong River basin. To verify this migration, elemental concentrations were measured in the water and in otoliths to infer the salinity of the water through the fish's lifetime. In 2017, eight element concentrations were measured along the Mekong Delta using solution-based inductively coupled plasma mass spectrometry (ICP-MS). Concentrations of Sr, Li and Rb were strongly and positively correlated with salinity. Otoliths were taken from P. krempfi caught in the brackish waters of the lower Mekong Delta and seven element : Ca ratios were measured from the core to the otolith edge using laser ablation ICP-MS. The Sr : Ca, Ba : Ca, P : Ca and Mn : Ca ratios varied through the lifetime of the fish, but only Sr : Ca was suitable for estimating ambient salinity. The Sr : Ca profiles in otoliths were analysed and significantly correlated between individuals, with all fish hatched in water with very low levels of salinity, indicating a single freshwater spawning ground, and then living in waters with higher salinity, with two types of migration behaviour. Some individuals may return to low-salinity waters when older. These conclusions were supported by the Ba : Ca and Mn : Ca ratios. These migration patterns may have implications for fishery management. PY 2019 SO Marine And Freshwater Research SN 1323-1650 PU Csiro Publishing VL 70 IS 12 UT 000498228100009 BP 1734 EP 1746 DI 10.1071/MF18269 ID 70966 ER EF