, Volume 56, Issue 2–3, pp 249–256 | Cite as

Small scale spatial heterogeneity influences predation success in an unexpected way: Model experiments on the functional response of predatory mites (Acarina)

  • Heinrich Kaiser
Original Papers


A basic assumption usually made in measuring the functional response of a predator (predation rate) is that it depends on the density of the prey but not on the size, form, or small-scale spatial structure of the studied area. This assumption has been tested by experiments with the predatory mite Phytoseiulus persimilis and the spider mite Tetranychus urticae as prey.

In experiments carried out on arenas with different internal spatial structure the predators had a lower predation rate on those arenas with a higher degree of spatial heterogeneity. On arenas with no additional internal structure but of different shape the predation rate was highest on squares with a relatively short border. The differences in predation rate are explained by two effects. The borders influence the otherwise random movements of predator and prey in such a way that both stay slightly more often along the border. The shorter the total length of borders the higher is the probability of predator and prey meeting along a border; therefore predation rates on plain squares are higher than would be expected from completely random movements and distribution. In addition to this edge effect the arrangement of borders forming labyrinths results in a lower predation rate, probably by impeding searching movements. The encounter rate between predator and prey was much higher than the predation rate. Encounter rate and predation rate were not directly proportional.

It may be generally concluded that in predatory mites and probably in all other predators too, the functional response not only depends on the density of the prey but also on the size and the small-scale spatial structure of the experimental area or the habitat.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Amano H, Chant DA (1977) Life history and reproduction of two species of predacious mites, Phytoseiulus persimilis Athias-Henriot and Amblyseius andersoni (Chant) (Acarina: Phytoseiidae). Can J Zool 55:1978–1983Google Scholar
  2. Chant DA (1961) The effect of prey density on prey consumption and oviposition in adults of Typhlodromus (T.) occidentalis Nesbitt (Acarina: Phytoseiidae) in the laboratory. Can J Zool 39:311–315Google Scholar
  3. Everson P (1979) The functional response of Phytoseiulus persimilis (Acarina: Phytoseiidae) to various densities of Tetranychus urticae (Acarina: Tetranychidae). Can Ent 111:7–10Google Scholar
  4. Everson P (1980) The relative activity and functional response of Phytoseiulus persimilis (Acarina: Phytoseiidae) and Tetranychus urticae (Acarina: Tetranychidae): The effect of temperature. Can Ent 112:17–24Google Scholar
  5. Fernando MHJP, Hassell MP (1980) Predator-prey responses in an acarine system. Res Popul Ecol 22:301–322Google Scholar
  6. Fransz HG (1974) The functional response to prey density in an acarine system. Center for Agricultural Publishing and Documentation, WageningenGoogle Scholar
  7. Fujita K, Inoue T, Takafuji A (1979) Systems analysis of an acarine predator-prey system. I. Res Popul Ecol 21:105–119Google Scholar
  8. Hassell MP (1978) The dynamics of arthropod predator-prey systems. Princeton University PressGoogle Scholar
  9. Hassell MP (1980) Some consequences of habitat heterogeneity for population dynamics. Oikos 35:150–160Google Scholar
  10. Hassell MP, Lawton JH, Beddington JR (1976) The components of arthropod predation. I. The prey death-rate. J Anim Ecol 45:135–164Google Scholar
  11. Hassell MP, May RM (1974) Aggregation of predators and insect parasites and its effect on stability. J Anim Ecol 43:567–594Google Scholar
  12. Holling CS (1959a) The components of predation as revealed by a study of small-mammal predation of the European pine saw-fly. Can Ent 91:293–320Google Scholar
  13. Holling CS (1959b) Some characteristics of simple types of predation and parasitism. Can Ent 91:385–398Google Scholar
  14. Holling CS (1966) The functional response of invertebrate predators to prey density. Mem Ent Soc Can 48:1–86Google Scholar
  15. Huffaker CB (1958) Experimental studies on predation: Dispersion factors and predator-prey oscillations. Hilgardia 27:343–383Google Scholar
  16. Kaiser H (1975) Populationsdynamik und Eigenschaften einzelner Individuen. Verhandl Ges Ökologie, Erlangen, 25–38Google Scholar
  17. Kaiser H (1979a) The dynamics of populations as result of the properties of individual animals. Fortschr Zool 25:109–136Google Scholar
  18. Kaiser H (1979b) Räumliche Heterogenität und Beutefang von Raubmilben. Verh Dtsch Zool Ges 1979, 254Google Scholar
  19. Laing JE (1968) Life history and life table of Phytoseiulus persimilis Athias-Henriot. Acarologia 10:578–588Google Scholar
  20. Laing JE, Osborn JAL (1974) The effect of prey density on the functional and numerical responses of three species of predatory mites. Entomophaga 19:267–277Google Scholar
  21. Michaelis H (1978) Suchen Raubmilben die gleichen Stellen an Pflanzen auf wie ihre Beutetiere? Untersuchungen an Phytoseiulus persimilis Athias-Henriot (Acarina: Phytoseiidae) und Tetranychus urticae Koch (Acarina: Tetranychidae). Diplomarbiet Köln-Bayreuth, 1–108Google Scholar
  22. Mori H (1969) The influence of prey density on the predation of Amblyseius longispinosus (Evans) (Acarina: Phytoseiidae). Proc 2nd Int Congr Acarology 1967:149–153Google Scholar
  23. Mori H, Chant DA (1966a) The influence of prey density, relative humidity, and starvation on the predacious behaviour of Phytoseiulus persimilis Athias-Henriot (Acarina: Phytoseiidae). Can J Zool 44:483–491Google Scholar
  24. Mori H, Chant DA (1966b) The influence of humidity on the activity of Phytoseiulus persimilis Athias-Henriot and its prey, Tetranychus urticae (CL Koch) (Acarina: Phytoseiidae, Tetranychidae). Can J Zool 44:863–871Google Scholar
  25. Murdoch WW, Oaten A (1975) Predation and population stability. Adv Ecol Res 9:1–131Google Scholar
  26. Ohnesorge B (1978) Der Einfluß der Besiedlungsdauer spinnmil-benverseuchter Bohnenblätter auf die räumliche Verteilung der Raubmilbe Phytoseiulus persimilis A.-H. (Acarina: Phytoseiidae). Z ang Ent 85:337–340Google Scholar
  27. Ohnesorge B (1981) Populationsdynamiche Untersuchungen in einem Räuber-Beutetier-System: Phytoseiulus persimilis A.-H. (Acarina: Phytoseiidae) und Tetranychus urticae Koch; 1. Teil: Reproduktionswert, Verzehrwert und Verzehrpotential. Z ang Ent 91:25–49Google Scholar
  28. Rabbinge R (1976) Biological control of fruit-tree red spider mite. Centre for Agricultural Publishing and Documentation, WageningenGoogle Scholar
  29. Sabelis MW (1981) Biological control of two-spotted spider mites using phytoseiid predators. Part I. Centre for Agricultural Publishing and Documentation, WageningenGoogle Scholar
  30. Schliesske J (1981) Vergleichende Untersuchungen an Amblyseius channabasavanni und der in der biologischen Schädlingsbe-kämpfung eingesetzten Phytoseiulus persimilis (Acari: Phytoseiidae). Mitt dtsch Ges allg angew Ent 3:118–121Google Scholar
  31. Schmidt G (1976) Der Einfluß der von den Beutetieren hinterlassenen Spuren auf Suchverhalten und Sucherfolge von Phytoseiulus persimilis A-H. (Acarina: Phytoseiidae). Z ang Ent 82:216–218Google Scholar
  32. Solomon ME (1949) The natural control of animal populations. J Anim Ecol 18:1–35Google Scholar
  33. Takafuji A, Chant DA (1976) Comparative studies of two species of predacious phytoseiid mites (Acarina: Phytoseiidae), with special reference to their responses to the density of their prey. Res Popul Ecol 17:255–310Google Scholar
  34. Voit E (1976) Räumliche Verteilung und Häufigkeit des Zusammentreffens von Spinnmilben und Raubmilben (Tetranychus urticae und Phytoseiulus riegeli, Acarina). Diplomarbeit Köln, 1–91Google Scholar

Copyright information

© Springer-Verlag 1983

Authors and Affiliations

  • Heinrich Kaiser
    • 1
  1. 1.Lehrstuhl für Biologie V (Ökologie) der RWTH AachenAachenFederal Republic of Germany

Personalised recommendations