Ga. Finenko et Za. Romanova, Population dynamics and energetics of the ctenophore Mnemiopsis leidyi in Sevastopol Bay, OCEANOLOGY, 40(5), 2000, pp. 677-685
The population dynamics of the abundance and biomass were studied and the s
pecific production of population of the ctenophore Mnemiopsis leidyi was es
timated in Sevastopol Bay during one year (from January 1995 to March 1996)
. The ctenophores achieved maximum abundance and biomass in July during the
period of intensive reproduction. The young specimens (<5 mm) contributed
during that period as much as 50-87% to the total abundance of the populati
on. The annually averaged daily specific growth rate was 0.039. The growth,
food consumption, and the rate of filtration were measured in the laborato
ry under two concentrations of food (Acartia clausi and Moina micrura; 60 a
nd 100 specimens per liter, 0.35 and 0.60 mg wet weight/l). Both concentrat
ions sustained the growth of the animals with a dry weight less than 20 mg;
however, these concentrations were insufficient to sustain the growth of l
arger ctenophores. The specific growth rate of the ctenophores with a dry w
eight <20 mg under favorable food conditions was 0.20-0.30. The specific gr
owth rate of the ctenophores in Sevastopol Bay never exceeded 0.093, the me
an biomass of fodder zooplankton in the bay being 90 mg/m(3) in terms of we
t weight. Hence, the conclusion was made that the population of M. leidyi i
n the bay was limited by the lack of food.