Mass development of cladocerans
starts in June when they make up about 30% of the total zooplankton biomass; they dominate in biomass in July (mainly the genus Daphnia) and account for about 50% of biomass in the autumn months (genus Bosmina).
New and little know cladocerans
(Crustacea: Anomopoda) from southeastern Mexico.
The proportion of copepods (in the abundance of total zooplankton) in Lake Dridzis decreased from 56% in 1954 (Kumsare & Laganovska, 1959) to 40% in 2007 and that of cladocerans
from 23% to 13%.
made up such a small percentage of the zooplankton counted that they could not be accurately analyzed, this taxa is worth mentioning in context to this study as a majority of zooplankton-cyanobacteria studies use cladocerans
Range expansion and potential dispersal mechanisms of the exotic cladoceran
The predaceous European cladoceran
Bythotrephes cederstroemi (Schoedler) was first discovered in the Laurentian Great Lakes in the 1980s (Garton and others 1993), presumably introduced via freshwater ballast of ships from European ports during peak shipping traffic of the late 1970s and early 1980s (Sprules and others 1990).
biomass was built up of species from the genus Bosmina (B.
The calanoid:cyclopoid plus cladoceran
ratio is specifically applicable for detecting differences in trophic status among water masses of differing eutrophy in the Laurentian Great Lakes (Stemberger & Gannon 1978), however, care must be taken to use it elsewhere.
Balcher (1983) found that young rainbow smelt (Osmerus mordax) prefer copepods to cladocerans
, locating cladocerans
from a similar distance to copepods but avoiding attacks on the spiny cladoceran
Schaefer and Miura (1990) similarly reported a reduction in fecundity of mixed populations of cladocerans
and ostracods at pyriproxyfen exposure levels of 31 nM (Schaefer and Miura 1990).
Additional small prey taxa are commonly reported in Pacific herring and other species diets, including invertebrate eggs, barnacle larvae, cladocerans
, oikopleurans, and juvenile amphipods and euphausiids (Wailes, 1936; Sherman and Perkins, 1971; Last, 1989; Arrhenius and Hansson, 1994; Arrhenius, 1996; Haegele, 1997; Willette et al.
Resting eggs are very tolerant of extreme environmental conditions, such as freezing and drying, and ensure the survival of cladoceran
populations during the winter, from which new asexually reproducing females hatch in spring.
"bloom" in October accompanied a decrease in phytoplankton populations.
The cosmopolitan cladoceran
genus Daphnia is considered as a taxonomically difficult complex due to its variable morphological features.
1st records of a European cladoceran
, Bytbotrephes cederstroemi, in Lakes Erie and Huron.