Strontium isotope mapping and its application to study the fish life history (Salminus brasiliensis) in semi-fragmented rivers (La Plata Basin, South America)

2023

Article référencé dans le Web of Science WOS:001002064500001

Avigliano E., Chung M. T., Pouilly Marc, Huang K. F., Casalinuovo M., Dominino J., Silva N., Sanchez S., Facetti J. F., Volpedo A. V.

Fisheries Research, 2023, 265, p. 106741 [10 p.] ISSN 0165-7836

Salminus brasiliensis is one of the largest and most important commercial and sporting fish species in South America, of which little is known about its habitat use, especially in semi-fragmented rivers. The aims of this study were to expand the water 87Sr/86Sr baseline of the La Plata Basin, and to study the migratory patterns of S. brasiliensis from Paran ' a dam-free stretch and a representative tributary semi-fragmented using otolith isotopic chemistry. Water samples were collected at 10 sites on the upper Paran ' a River and two sites on the middle and lower Carcaraña Basin (tributary of the lower Paran ' a River). Fourteen fish were caught in the upper Paran ' a River and 13 in two sites of the middle and lower Carcaran similar to ' a Basin. 87Sr/86Sr was measured in water and otolith core-to-edge transect by MC-ICPMS and LA-MC-ICPMS, respectively. Water results were incorporated into a dataset with 53 other sampling points from the La Plata Basin and subjected to a cluster analysis, which resulted in nine differentiable chemical signatures. Discriminant analysis confirmed the presence of at least eight contrasting isotopic signals. Based on the otolith core 87Sr/86Sr, four individuals from the upper Paran ' a River were classified as originating from Paraguay sub-basin, while the rest were assigned to Paran ' a River. All fish from the Carcaran similar to a ' sub-basin were classified as originating from the Paran ' a River, except two individuals which were assigned to the Carcaran similar to ' a sub-basin. Results indicated that the fish run up the Carcaran similar to ' a sub-basin overcoming up to three open spillways, and could live there for years and even reproduce. However, the Paran ' a River had the largest contribution to the fish caught in both the upper Paran ' a River and the Carcaran similar to ' a sub-basin.

Limnologie biologique / Océanographie biologique [034] ; Ressources halieutiques [040]

AMERIQUE DU SUD ; LA PLATA BASSIN

Fonds IRD [F B010088118]

fdi:010088118