Aquatic Sciences Meeting, Albuquerque 2001

PC01 Harmful Algal Blooms

Date: Tuesday, February 13, 2001

Location: Southwest Hall

Kozlowsky-Suzuki, B, , Dept of Marine Sciences, University of Kalmar, Kalmar, Sweden, betina.suzuki@hik.se

Karjalainen, M, , University of Helsinki, Helsinki, Finland, miina.karjalainen@helsinki.fi

Koski, M, , University of Helsinki, Helsinki, Finland, makoski@touko.helsinki.fi

Viherluoto, M, , University of Helsinki, Helsinki, Finland, maiju.viherluoto@helsinki.fi

Engstrom, J, , University of Helsinki, Helsinki, Finland, jonna.engstrom@helsinki.fi

Carlsson, P, , University of Kalmar, Kalmar, Sweden, per.carlsson@hik.se

Stolte, W, , University of Kalmar, Kalmar, Sweden, willem.stolte@hik.se

Graneli, E, , University of Kalmar, Kalmar, Sweden, edna.graneli@hik.se

GRAZING AND EGG PRODUCTION OF ACARTIA SPP. ON SUMMER CYANOBACTERIA ASSEMBLAGES IN THE BALTIC SEA

Grazing and egg production of Acartia spp. were studied in a mesocosm experiment with a natural phytoplankton community from the Baltic Proper and in shipboard incubations in the Gulf of Finland. In the first experiment, polyethylene cylinders (300 L) received daily additions of nitrate and dissolved organic matter (DOM) alone or in combination with iron. Copepods fed significantly on Anabaena spp., but not on the other filamentous cyanobacteria, at least in the nitrate treatment. Egg production ranged from 0 to 18 eggs/female/day. It was highest in the nitrate treatment and lowest in the DOM+Fe treatment, where Anabaena spp. biomass was highest. In the shipboard experiment the treatments consisted of the natural plankton community containing cyanobacteria, a toxic Nodularia spumigena strain alone or in combination with a culture of the green flagellate Brachiomonas submarina. In this experiment, egg production ranged from 0.45 to 7 eggs/female/day, with the highest egg production in the Nodularia + Brachiomonas treatment, followed by the natural community and the Nodularia treatment. Our results show that egg production decreased when filamentous cyanobacteria was the dominating food source.

This Session Listing

Aquatic Sciences Meeting, Albuquerque 2001

Quicklinks