Effects of varying food and density on reproduction in Diaptomus clavipes Schacht

Abstract

This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, contractors, subcontractors, or their employees, makes any warranty, express or implied, nor assumes any legal liability or responsibility for any third party's use or the results of such use of any information, apparatus, product or process disclosed in this report, nor represents that its use by such third party would not infringe privately owned rights.

The influence of food concentration and container volume on life history parameters of Diaptomus dorsalis Marsh from subtropical Florida

“…These departures from maximum responses have also been noted, for one or more of the parameters I studied, in rotifers (King 1967;Makarewicz & Likens 1979), cladocerans (Banta et al 1939;Hall 1964;Weglenska 1971;Vijverberg 1976;Makarewicz & Likens 1979), estuarine and marine copepods (Marshall & Orr 1952;Corkett & McLaren 1970;Mullin & Brooks 1970; 1970), freshwater cyclopoids (Coker 1933;Elgmork & Halvorsen 1976) and other freshwater calanoids (Eckstein 1964;Cooney et al 1978). However, food concentration has also been found to have no effect on one or more of the parameters examined in all of the taxa listed above (Coker 1933;Hall 1964;Corkett & McLaren 1969;Robertson et al 1974;Makarewicz & Likens 1979).…”

“…There have been many studies of the effects of food concentration on rotifers (e.g., King 1967;Makarewicz & Likens 1979;Snell 1979), on cladocerans (e.g., Banta et al 1939;Slobodkin 1954;Hall 1964;Schindler 1968;Vijverberg 1976;Makarewicz & Likens 1979) and on marine and estuarine copepods (e.g., Marshall & Orr 1952;Corkett & McLaren 1969Mullin & Brooks 1970;Paffenhofer 1970). However, little work has been done on the effects of food concentration on freshwater cyclopoids (Coker 1933;Elgmork & Halvorsen 1976) or calanoids (Eckstein 1964;Robertson et al 1974;Cooney et al 1978). Moreover, these studies of freshwater copepods have been concerned only with temperate zone species and the experiments performed are not strictly repeatable since rigorously defined media and food were not always used.…”

“…The effects of container volume and animal density should be essentially the same since equilibrium population sizes of rotifers (King 1967;Snell 1979) and cladocerans (Slobodkin 1954) have been shown to vary linearly with food concentration. Little work on density effects has involved copepods (Whitehouse & Lewis 1973;Robertson et al 1974;Cooney et al 1978) and these studies were of temperate zone species and did not use strictly repeatable conditions. No laboratory studies have been done on tropical or subtropical freshwater copepods in relation to food concentration or container volume.…”

Factors regulating the reproductive phenology of Onychodiaptomus birgei (Copepoda: Calanoida)1

“…When females at 2 1 "C were divided into three treatments [high food, low food (control), and starvation] starved animals stopped producing eggs, as Cooney et al (1978) observed for Agalodiaptomus clavipes. All starved animals produced clutches comprised of subitaneous eggs after a return to low food levels.…”

Factors influencing Diaptomus distributions: An experimental study in subtropical Florida1

“…Life history parameters of calanoids change with decreased food levels under defined laboratory conditions (Cooney et al 1978;Elmore 1982). Low food concentrations result in smaller body sizes and clutch sizes, lowered survivorship, and longer development times.…”