Spatial and temporal distribution of landlocked Galaxias maculatus and Galaxias platei (Pisces, Galaxiidae) in a lake in the South American Andes

BARRIGA, J.P.; M.A. BATTINI; P.J. MACCHI; D. MILANO; V.E. CUSSAC

NEW ZEALAND JOURNAL OF MARINE AND FRESHWATER RESEARCH

The Royal Society of New Zealand

Año: 2002 vol. 36 p. 349 - 363

0028-8330

Galaxiids are present in many of the Andean lakes in southern South America. We studied landlocked Galaxias maculatus (Jenyns) andGalaxias maculatus (Jenyns) and Galaxias platei Steindachner populations in a deep oligotrophic lake (Lake Gutiérrez, Patagonia, Argentina). Their temporal and spatial distribution, intralacustrine movements (horizontal and vertical), and spawning periods were analysed using several sampling techniques (ichthyoplankton net, seine net, gill net, and baited benthic traps). We identified the early life stages of both species based on their morphology and otolith shape. The free embryos of both species migrate to the limnetic zone, where they coexist as larvae, facing the same food availability and probably the same predation risk. Each species then moves on to its own juvenile and adult habitat: the littoral and benthic zone for G. maculatus and only the deeper benthic zone for G. platei. Their adult habitats and part of their spawning periods partly overlap.Steindachner populations in a deep oligotrophic lake (Lake Gutiérrez, Patagonia, Argentina). Their temporal and spatial distribution, intralacustrine movements (horizontal and vertical), and spawning periods were analysed using several sampling techniques (ichthyoplankton net, seine net, gill net, and baited benthic traps). We identified the early life stages of both species based on their morphology and otolith shape. The free embryos of both species migrate to the limnetic zone, where they coexist as larvae, facing the same food availability and probably the same predation risk. Each species then moves on to its own juvenile and adult habitat: the littoral and benthic zone for G. maculatus and only the deeper benthic zone for G. platei. Their adult habitats and part of their spawning periods partly overlap.G. maculatus and only the deeper benthic zone for G. platei. Their adult habitats and part of their spawning periods partly overlap.G. platei. Their adult habitats and part of their spawning periods partly overlap.