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Calculations of results in grazing experiments using the counting method

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Abstract

Different formulae used in the literature for calculation of ingestion rates are reviewed. Their applicability is discussed in relation to two criteria: the occurrence of saturation of the feeding and/or growth of the food particles. It is shown by simulations that the differences in results obtained by calculating ingestion following a linear or an exponential model are restricted to a few percent. Calculation of ingestion rates by subtraction of particle concentrations from control and grazing bottles can result in substantial over- or underestimation depending on the growth constant of the food particles and the grazing time.

The formule l=Vk(Czt−Czoekt)/N(l−ekt) is proposed for the calculation of ingestion rates under saturated circumstances.

It is demonstrated that, with data obtained by multi-size class analysis, calculations on total particle concentrations are only feasible when growth constants and grazing coefficients are equal for all size classes considered.

Attention is drawn to calculation problems resulting from non-normally distributed results and from non equal particle concentrations in control and grazing bottles at the beginning of the experiment. For the latter problem, two correction methods are proposed.

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References

  1. BARETTA, J.W. and J.F.P. MALSCHAERT, 1985. Experimental problems using electronic particle counters. Hydrobiological Bulletin 19: 21–27.

  2. FROST, B.W., 1972. Effects of size and concentration of food particles on the feeding behaviour of the planktonic copepodCalanus pacificus. Limnol. Oceanogr., 27: 805–815.

  3. GAULD, D.T., 1951. The grazing rate of planktonic copepods. J. Mar. Biol. Ass. U.K., 29: 695–706.

  4. MULLIN, M.M., 1963. Some factors affecting the feeding of marine copepods of the genusCalanus. Limnol. Oceanogr., 8: 239–250.

  5. PAFFENHOFER, G.A., J.R. STRICKLER and N. ALCARAZ, 1982. Suspension-feeding by herbivorous calanoid copepods: a cinematographic study. Mar. Biol., 67: 193–199.

  6. POULET, S.A., 1973. Grazing ofPseudocalanus minutus on naturaly occurring particulate matter. Limnol. Oceanogr., 18: 564–573.

  7. PRICE, H., G.A. PAFFENHOFER and J.R. STRICKLER, 1983. Modes of cell capture in calanoid copepods. Limnol. Oceanogr., 28: 116–123.

  8. RIGLER, F.H., 1971. Feeding rates-Zooplankton. In: EDMONDSON, W.T. and G.G. WINBERG e.d., 1971. Secondary Productivity in Fresh waters. Blackwell Scientific publications Oxford and Edinburg, p. 228–256.

  9. SHELDON, R.W., A. PRAKASH and W.H. SUTCLIFFE, Jr., 1972. The size distribution of particles in the ocean. Limnol. Oceanogr., 27: 327–340.

  10. VANDERPLOEG, H.A., 1981. Seasonal particle-size selection byDiaptomus sicilis in offshore Lake Michigan. Can. J. Fish. Aquat. Sci., 38: 504–517.

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Communication no. 327 of the Delta Institute for Hydrobiological Research.

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Tackx, M.L.M., Van De Vrie, E.M. Calculations of results in grazing experiments using the counting method. Hydrobiological Bulletin 19, 29–36 (1985). https://doi.org/10.1007/BF02255090

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Keywords

  • grazing
  • Coulter counter
  • clearance rate
  • ingestion rate