Daily vertical distribution of zooplankton in two oligo-mesotrophic north Patagonian lakes (39° S, Chile)

• Published in: Brazilian journal of biology Vol. 81; no. 3; pp. 642 - 649
• Main Authors: Ríos-Escalante, P De Los, Valdivia, P, Woelfl, S
• Format: Journal Article
• Language: English
• Published: Brazil Association of the Brazilian Journal of Biology 01-07-2021; Instituto Internacional de Ecologia
• Subjects: Animals; BIOLOGY; Ceriodaphnia dubia; Chile; cladocera; copepod; Crustaceans; daily vertical migration; Daphnia pulex; Lakes; Mesocyclops; Northern Hemisphere; Oligotrophic lakes; Patagonian lakes; Plankton; Predation; Radiation effects; Summer; Tropocyclops prasinus; Ultraviolet radiation; Ultraviolet Rays; Vertical distribution; Vertical migrations; Zooplankton; Chile; Argentina; lagos patagônicos; daily vertical migration; copépodes; cladocera; migração vertical diária; zooplankton; Patagonian lakes; copepod; zooplâncton; cladóceros
• ISSN: 1519-6984; 1678-4375; 1678-4375
• DOI: 10.1590/1519-6984.227942

The zooplankton communities often exhibit daily vertical migrations to avoid natural ultraviolet radiation and/or fish predation. However there is no information on this topic in Chilean North Patagonian lakes up to date. Therefore, this study deals with a first characterization of plankton crustacean daily vertical migration in two temperate, oligotrophic lakes (Villarrica and Panguipulli lakes, 39°S) in Southern Chile. Zooplankton were collected at different depths intervals (0-10m, 10-20 m, 20-30m, 30-40m) at early morning, middle day, evening and night in the studied site. The results revealed that zooplankton species (Daphnia pulex, Ceriodaphnia dubia, Neobosmina chilensis, Mesocyclops araucanus, and Tropocyclops prasinus) are abundant in surface zones at night, early morning and evening, whereas at middle day the zooplankton abundances are high at deep zones. The results agree with observations for Argentinean and North American lakes where these daily migration patterns in crustacean zooplankton species were reported due mainly natural ultraviolet radiation exposure, whereas for northern hemisphere lakes the vertical migration is due to combined effect of natural ultraviolet radiation and fish predation exposure.