Relationships between the nutritional environment and copepod egg production were investigated in Acartia tonsa from the Port Everglades estuary (Ft. Lauderdale, Florida) and in Centropages velificatus, Temora stylifera, and Undinula vulgaris from the eastern Gulf of Mexico. Egg production was measured by incubation procedures. Female copepods were incubated either individually (in 250 mL containers) or in groups of 5-10 (in 2 liter containers) for 24 hours. The concentration of particulate protein, lipid, and water-soluble carbohydrate was determined in size-fractionated microplankton samples (1-8 um, 8-100 um). Correlations were identified between egg production (transformed to carbon-specific and protein-specific production), the nutritional environment and the physical environment (i.e. temperature) by least squares techniques.
Significant species-specific correlations were detected between nutrient composition and egg production. The nutrients utilized by copepods for energy (carbohydrates and lipids) appear to be important to the egg production of A. tonsa and C. velificatus.
During the spring, protein-specific production in C. velificatus varied inversely with the lipid concentrations of both particle size classes (1-100 um and 8-100 um) (correlation coefficient [r] = -0.62, significance level [P] < 0 .05, number of data points [n] = 12) and water temperature (r = -0.62, P < 0.05, n = 12) . Protein-specific production in Acartia tonsa was correlated with seston water-soluble carbohydrate concentrations in the seston (r = 0.88, P < 0.05, n = 10 ) except during a diatom bloom which occurred in June 1993.
Multi-variate analysis revealed a strong relationship between protein- and carbon-specific production of A. tonsa and nutrients utilized for energy (carbohydrates and lipids) (r = 0.91, P < 0.001, n = 9). Centropages velificatus protein- and carbon-specific production was significantly correlated with the combination of water-soluble carbohydrate and protein concentrations in the seston (8-100 um) (r = 0.72, P < 0.05, n = 14).
Estimated ingestion rates suggest copepod species feed at different rates in order to obtain the same percentage of body nutrients. This may be due, in part, to the relationship between the nutrient content of a particular species and the seston nutrient concentrations observed in their distinct environments.
| Identifer | oai:union.ndltd.org:nova.edu/oai:nsuworks.nova.edu:occ_stuetd-1050 |
| Date | 01 January 1995 |
| Creators | Carter, Kevin |
| Publisher | NSUWorks |
| Source Sets | Nova Southeastern University |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | Theses and Dissertations |
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