ISSN:
1573-5117
Keywords:
zooplankton
;
grass carp
;
lakes
;
Hydrilla
;
vegetation
;
Ctenopharyngodon idella
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract Zooplankton populations were monitored monthly for a three year period in four Florida lakes. Each lake received an aquatic vegetation control program using grass carp (Ctenopharyngodon idella Val.) and herbicide, either alone or in combination. All aquatic vegetation was eliminated in the three lakes with grass carp; it was severely reduced and exhibited qualitative shifts in the lake treated with herbicide alone. Total number of recorded zooplankton species was reduced in each subsequent year as vegetation was eliminated, but mean density l−1 increased greatly. The overall trend in all lakes was toward increasing numbers of small filter-feeding herbivores, with a shift from copepod and copepod-cladoceran dominated to rotifer and small cladoceran dominated systems. It is suggested that these changes reflect primary plankton response to fluctuations in habitat, food base, and planktivore pressure resulting from gradual macrophyte alteration. Changes observed indicate apparent increases in eutrophy.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00018972
