Reproduction rates and secondary production of three species of the rotifer genus Synchaeta in the estuarine Potomac River

Trophic role of planktonic rotifers in the Rhode River Estuary, spring-summer 1991

“…Production of Synchaeta cecilia was estimated using abundance figures from field samples, a biomass conversion factor (0.0168 pg C S. cecilia-l) from the literature (Heinbokel et al 1988), and growth rates derived from 2 different methods. For the 5 dates on which grazing experiments were run, growth rates from the control chambers were used.…”

“…ER was determined by microscopic examination and EDT was calculated using the equation of Heinbokel et al (1988) relating incubation temperature (in situ water temperature, T in "C) to EDT for Synchaeta cecilia:…”

“…Resource competition between the 2 groups could have complicated a rotifermicroflagellate relationship. Because ciliates can sustain growth at much lower food concentrations than rotifers (Heinbokel et al 1988), ciliate numbers should increase and rotifers decrease when food levels are low. While field patterns are rarely unambiguous, no such relationship was obvious (Fig.…”

“…While considered characteristic of freshwaters (Pennak 1978), they are known to occur in estuarine and marine waters and are apparently restricted to coastal areas due to high nutritional requirements (Heinbokel et al 1988). However, beyond these generalities little is known of the importance of their ecological role in estuarine and marine systems, due largely to a lack of reliable quantitative data.…”

An experimental test of the egg‐ratio method with instantaneous birth rate as an independent variable

“…Heinbokel et al 1988). These rates can seldom be measured directly in the field, however, and usually are calculated from mathematical models.…”