|Growth dynamics of a ctenophore (Mnemiopsis) in relation to variable food supply: I. Carbon biomass, feeding, egg production, growth and assimilation efficiency|Reeve, M.R.; Syms, M.A.; Kremer, P. (1989). Growth dynamics of a ctenophore (Mnemiopsis) in relation to variable food supply: I. Carbon biomass, feeding, egg production, growth and assimilation efficiency. J. Plankton Res. 11(3): 535-552. hdl.handle.net/ 10.1093/plankt/11.3.535
In: Journal of Plankton Research. Oxford University Press: New York,. ISSN 0142-7873; e-ISSN 1464-3774, meer
Mnemiopsis L. Agassiz, 1860 [WoRMS]
|Auteurs|| || Top |
- Reeve, M.R.
- Syms, M.A.
- Kremer, P.
This paper contains new experimental data on the growth dynamics of a lobate coastal ctenophore, Mnenmiopsis mccradyi, which add significantly to our understanding of the nutritional ecology of ctenophores and their role as opportunistic predators. These experimental observations were necessary to refine the dynamic carbon budget presented as a simulation model in another report. The ratio of carbon biomass to dry weight may vary several-fold depending on the nutritional state and size from >12% in well-fed larvae to <1% in starved adults. Feeding effort (clearance rate) is higher for previously starved animals, falling sharply within a few hours after re-exposure to food. Direct visual observations of feeding activity of animals confirmed this. Assimilation efficiency can be high (72%) in these animals but if they continue to feed at high food concentrations, incoming food displaces material which is only partially digested and assimilation efficiency decreases substantially. Except at very low food concentrations, growth efficiency ranges between 20 and 45%. Mnemiopsis, begins to produce eggs at a size much less than its maximum. Egg production is very sensitive to food supply, and somatic growth is favored over egg production at low food densities. Even though several thousand eggs may be produced over a few days, they represent <2% day-1 of the carbon biomass of the ctenophore and several-fold less than respiratory carbon.