Habitat use of the amphidromous catfish Genidens barbus : first insights at its southern distribution limit

AVIGLIANO, ESTEBAN; PISONERO, JORGE; MÉNDEZ, ANA; TOMBARI, ANDREA; VOLPEDO, ALEJANDRA V.

NEW ZEALAND JOURNAL OF MARINE AND FRESHWATER RESEARCH

RSNZ PUBLISHING

Lugar: Auckland; Año: 2021 p. 1 - 7

0028-8330

White sea catfish Genidens barbus is an endangeredamphidromous species distributed between northeastern Braziland northern Argentine Patagonia, whose migratory behaviour atthe southern end of its range is unknown. Here, the migratorypatterns of this species were studied including marine andfreshwater (Patagonian stock) environments via otolith core-toedge Sr/Ca and Ba/Ca profiles. Based on the Sr/Ca ratio, allspecimens were classified as amphidromous with annual cycles ofmovement between waters of relatively low to high salinityoccurring during spring. The core Sr/Ca ratio matched with thereference values for freshwater in all specimens. No evidence ofresident freshwater or marine individuals was found. No evidentantagonistic relationship was found between both Sr/Ca and Ba/Ca ratios. A Ba/Ca peak was observed followed by a dropcoinciding with the core edge, highlighting the need to evaluatethe potential transfer from the yolk, and to understand whatfactors are linked to the growth marks within the first year of life