@article{2a3894eefb9d45bb8cdf0f74bf4483aa,
title = "Life history strategies of Mekong pangasiid catfishes revealed by otolith microchemistry",
abstract = "Fourteen species of pangasiid catfish are found in the Mekong River. They are key components of both capture fisheries and aquaculture, although little is known about their migratory ecology, which is particularly important as some species are in decline. In order to examine the life-history strategies of key pangasiid catfishes in the Mekong River, we collected otoliths from 126 specimens belonging to four species in the Lower Mekong Basin. We analysed the otolith microchemical structure using two methods (Laser Ablation – Inductively Coupled Plasma Mass Spectrometry and Scanning X-ray Fluorescence Microscopy) to identify evidence of diadromy (movements between the ocean and upstream waters). We followed an established method of examining patterns of strontium to calcium (Sr:Ca) and barium to calcium (Ba:Ca) ratios along otolith transect profiles to interpret whether fish were in fresh or salt water at various stages of their life. We confirmed anadromy in two species (Pangasius krempfi and P. mekongensis; spawning in river but growing in marine waters) with at least three migratory tactics identified for each species, thus highlighting more diverse life history strategies than previously thought. Based on locations where we collected fish, we can infer these species migrate up to 700 km (P. mekongensis) and 1400 km (P. krempfi) from the sea into the Mekong River for spawning. The other two catfishes (P. elongatus and P. bocourti) appeared to be freshwater species that occasionally strayed into the estuary. Long-distance migratory species require free flowing rivers to connect critical habitats used at different life stages. Any activity disrupting these migratory pathways and disconnecting these habitats must be carefully considered. Conservation and management of transboundary species require international agreements to protect them from the impacts of river development, and the evidence presented here is pertinent for catfish in the Mekong River.",
keywords = "Anadromy, Diadromy, Fish migration, Mekong River, Trace metals",
author = "Vu, {An V.} and Baumgartner, {Lee J.} and Limburg, {Karin E.} and Doran, {Gregory S.} and Martin Mallen-Cooper and Gillanders, {Bronwyn M.} and Thiem, {Jason D.} and Howitt, {Julia A.} and Kewish, {Cameron M.} and Juliane Reinhardt and Cowx, {Ian G.}",
note = "Funding Information: We thank the Australia Awards Scholarship, National Geographic, Australian Centre for International Agricultural Research, and Delft-International Institute for Hydraulic and Environmental Engineering for financial support for this study. This study could not have been completed without support and sampling assistance of many people due to travel restrictions of Covid-19 including from the National University of Laos (Oudom Phonekhampeng, Thonglom Phommavong, Gary Thorncraft, and Phousone Vorassane), Charles Sturt University (Wayne Robinson), Don Sahong Power Company (Somphone Phommanivong and Kent Hortle), and Inland Fisheries Research and Development Institute (Chan Sokheng) and local fishers who collected rare fish species. Also, we are appreciated with technical support from the University of Adelaide (Sarah Gilbert), Australian Synchrotron (David Paterson), Fisheries NSW (Kate Martin and Nathan Miles). Their assistance is appreciated and gratefully acknowledged. Part of this research was undertaken on the XFM beamline at the Australian Synchrotron, part of ANSTO. We are grateful Charles Sturt University's Institute for Land, Water and Society provided financial support to enable publication of this paper. We declare that we have no conflicts of interest. Mr. An V. Vu is an Australia Awards scholar but the views and opinions expressed in this paper do not represent the views of the Australian Government. Funding Information: We thank the Australia Awards Scholarship, National Geographic, Australian Centre for International Agricultural Research, and Delft-International Institute for Hydraulic and Environmental Engineering for financial support for this study. This study could not have been completed without support and sampling assistance of many people due to travel restrictions of Covid-19 including from the National University of Laos (Oudom Phonekhampeng, Thonglom Phommavong, Gary Thorncraft, and Phousone Vorassane), Charles Sturt University (Wayne Robinson), Don Sahong Power Company (Somphone Phommanivong and Kent Hortle), and Inland Fisheries Research and Development Institute (Chan Sokheng) and local fishers who collected rare fish species. Also, we are appreciated with technical support from the University of Adelaide (Sarah Gilbert), Australian Synchrotron (David Paterson), Fisheries NSW (Kate Martin and Nathan Miles). Their assistance is appreciated and gratefully acknowledged. Part of this research was undertaken on the XFM beamline at the Australian Synchrotron, part of ANSTO. We are grateful Charles Sturt University{\textquoteright}s Institute for Land, Water and Society provided financial support to enable publication of this paper. Publisher Copyright: {\textcopyright} 2022 Elsevier B.V.",
year = "2022",
month = may,
doi = "10.1016/j.fishres.2022.106239",
language = "English",
volume = "249",
pages = "1--16",
journal = "Fisheries Research",
issn = "0165-7836",
publisher = "Elsevier",
}
