240
Exercise 16
where N = average numbers/time interval; ~V = average weight increment; and
Te + p = development time from hatching to hatching.
How does this method differ from that outlined in this exercise? What is assumed?
APPARATUS AND SUPPLIES
1. Culture of nearly monospecific Daphnia. (A large fiberglass or similar tank
containing 200 to 500 I of water may be inoculated with a Daphnia population
collected from a particular layer of a stratified lake several weeks in advance of
this exercise. The Daphnia may be fed adequately by daily additions of a water
slurry of dog food.)
2. Screening sieves of differing mesh sizes (Plexiglas cylinders ca. 10 cm in diameter
and 6 cm high with the differing sizes of Nitex mesh glued over one end work very
well).
3. Dissecting microscopes.
4. Petri dishes, probes (insect needles with heads removed, inserted into wooden
match sticks), and mechanical counters.
References
Edmondson, W.T. 1974. Secondary production. Mitt. Int. Ver. Limnol. 20:229-272.
Edmondson, W.T. and G.G. Winberg (eds). 1971. A Manual on Methods for the Assessment
of Secondary Productivity in Fresh Waters. IBP Handbook 17. Blackwell, Oxford. 358 pp.
Haney, J.F. and D.J. Hall. 1973. Sugar-coated Daphnia: A preservation technique for
Cladocera. Limnol. Oceanogr. 18: 331-333.
Likens, G.E. and J.J. Gilbert. 1970. Notes on quantitative sampling of natural populations of
planktonic rotifers. Limnol. Oceanogr. 15: 816·-820.
Prepas, E. 1978. Sugar-frosted Daphnia: An improved fixation technique for Cladocera.
Limnol. Oceanogr. 23:557-559.
Rigler, F.H. and lA. Downing. 1984. The calculation of secondary productivity. pp. 19-58.
In: lA. Downing, and F.H. Rigler, Editors. A Manual on Methods for the Assessment of
Secondary Productivity in Fresh Waters. 2nd Ed. Blackwell, Oxford.
Winberg, G.G. (ed.) 1972. Methods for the Estimation of Production of Aquatic Animals.
Academic Press, New York. 175 pp.
Exercise 16
where N = average numbers/time interval; ~V = average weight increment; and
Te + p = development time from hatching to hatching.
How does this method differ from that outlined in this exercise? What is assumed?
APPARATUS AND SUPPLIES
1. Culture of nearly monospecific Daphnia. (A large fiberglass or similar tank
containing 200 to 500 I of water may be inoculated with a Daphnia population
collected from a particular layer of a stratified lake several weeks in advance of
this exercise. The Daphnia may be fed adequately by daily additions of a water
slurry of dog food.)
2. Screening sieves of differing mesh sizes (Plexiglas cylinders ca. 10 cm in diameter
and 6 cm high with the differing sizes of Nitex mesh glued over one end work very
well).
3. Dissecting microscopes.
4. Petri dishes, probes (insect needles with heads removed, inserted into wooden
match sticks), and mechanical counters.
References
Edmondson, W.T. 1974. Secondary production. Mitt. Int. Ver. Limnol. 20:229-272.
Edmondson, W.T. and G.G. Winberg (eds). 1971. A Manual on Methods for the Assessment
of Secondary Productivity in Fresh Waters. IBP Handbook 17. Blackwell, Oxford. 358 pp.
Haney, J.F. and D.J. Hall. 1973. Sugar-coated Daphnia: A preservation technique for
Cladocera. Limnol. Oceanogr. 18: 331-333.
Likens, G.E. and J.J. Gilbert. 1970. Notes on quantitative sampling of natural populations of
planktonic rotifers. Limnol. Oceanogr. 15: 816·-820.
Prepas, E. 1978. Sugar-frosted Daphnia: An improved fixation technique for Cladocera.
Limnol. Oceanogr. 23:557-559.
Rigler, F.H. and lA. Downing. 1984. The calculation of secondary productivity. pp. 19-58.
In: lA. Downing, and F.H. Rigler, Editors. A Manual on Methods for the Assessment of
Secondary Productivity in Fresh Waters. 2nd Ed. Blackwell, Oxford.
Winberg, G.G. (ed.) 1972. Methods for the Estimation of Production of Aquatic Animals.
Academic Press, New York. 175 pp.