, Volume 62, Issue 2, pp 256–261 | Cite as

Effects of water depth on choice of spatially separated prey by Notonecta glauca L.

  • Barbara J. Cockrell
Original Papers


In laboratory experiments, the predator, Notonecta glauca L., was exposed to varying densities of surfacedwelling culicine mosquito larvae and the bottom-inhabiting isopod, Asellus aquaticus L., in either shallow or deep water at 20° C. At this temperature N. glauca spends most of the time at the water's surface, so, by changing water depth the accessibility of Asellus to the predator was manipulated relative to a consistent Culex presence.

All N. glauca spent more time submerged in shallow (75 mm) than in deep (275 mm) water but submergence times were independent of exposure to different prey combinations. Mature females made more descents and remained submerged longer than males.

All N. glauca captured more Asellus in shallow than in deep water but males and newly-moulted females captured Culex predominantly, in all treatments, regardless of water depth or prey availability. Mature females captured mostly Asellus in shallow water and Culex in deep water. When presented with small rather than large Asellus, mature females spent an equivalent amount of time submerged as in the large Asellus treatments and ate the same number of Asellus but more Culex.

By foraging on Culex larvae, male and newly moulted female N. glauca maximise their rate of energy intake. In contrast, mature females may actively select Asellus to optimise something other than energy (e.g. specific nutrients). Alternatively their predation on Asellus may be simply a consequence of a high encounter rate with this prey type, reflecting habitat use determined by factors that do not concern prey capture directly.


Water Depth Laboratory Experiment Shallow Water Deep Water Energy Intake 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Alexander R, McNeil (1971) Animal mechanics. Sidgwick & Jackson, LondonGoogle Scholar
  2. Charnov EL (1976) Optimal foraging: attack strategy of a mantid. Am Nat 110:141–151Google Scholar
  3. Cockrell BJ (1980) A study of predation by Notonecta glauca (L.). Unpublished D. Phil. thesis, University of OxfordGoogle Scholar
  4. Cockrell BJ (1984) Effects of temperature and oxygenation on predator-prey overlap and prey choice of Notonecta glauca. J Anim Ecol (in press)Google Scholar
  5. Cook RM, Hubbard SF (1977) Adaptive searching strategies in insect parasites. J Anim Ecol 46:116–125Google Scholar
  6. Cummins KW, Wuycheck JC (1971) Caloric equivalents for investigations in ecological energetics. Int Ver Theor Angew Limnol Verh 18:1–158Google Scholar
  7. Emlen JM, Emlen MGR (1975) Optimal choice in diet: test of an hypothesis. Am Nat 109:427–435Google Scholar
  8. Giller PS (1979) The predation strategies and bionomics of three species of Nontonecta (Heteroptera/Hemiptera). Unpublished Ph.D. Thesis. University of LondonGoogle Scholar
  9. Goss-Custard JD (1977) Optimal foraging and the size selection of worms by redshank Tringa totanus. Anim Behav 25:10–29Google Scholar
  10. Greenberg B (1959) Housefly nutrition. 1. Quantitative study of the protein and sugar requirements of males and females. J Cell Comp Physiol 53:169–177Google Scholar
  11. Griffiths KJ (1969) The importance of coincidence in the functional and numerical responses of two parasites of the European pine sawfly, Neodiprion sertifer. Can Entomol 101:673–713Google Scholar
  12. Hassell MP, May RM (1974) Aggregation of predators and insect parasites and its effect on stability. J Anim Ecol 43:567–594Google Scholar
  13. Hassell MP, Southwood TRE (1978) Foraging strategies of insects. Ann Rev Ecol Syst 98:75–98Google Scholar
  14. House HL (1974) Nutrition. In: Rockstein, M (ed) The Physiology of Insecta, Vol. 5, Academic Press, London New York, pp 1–53Google Scholar
  15. Hubbard SF, Cook RM (1978) Optimal foraging by parasitoid wasps. J Anim Ecol 47:593–604Google Scholar
  16. Jaeger RG, Barnard DE (1981) Foraging tactics of a terrestrial salamander: choice of diet in structurally simple environments. Am Nat 117:639–664Google Scholar
  17. Kislalioglu M, Gibson RN (1976) Some factors governing prey selection by the 15-spined stickleback, Spinachia spinachia (L.). J Exp Mar Biol Ecol 25:159–169Google Scholar
  18. Krebs JR (1978) Optimal foraging: decision rules for predators. In: Krebs JR, Davies NB (eds) Behavioural Ecology: an Evolutionary Approach, Blackwell Scientific Publications, Oxford, pp 23–63Google Scholar
  19. Milinski M, Heller R (1978) Influence of a predator on the optimal foraging behaviour of sticklebacks (Gasteroteus aculeatus). Nature 275:642–644Google Scholar
  20. Murdoch WW (1969) Switching in general predators: experiments on predator specificity and stability of prey populations. Ecol Monogr 39:335–354Google Scholar
  21. Murdoch WW, Avery S, Smith MEB (1975) Switching in predatory fish. Ecology 56:1094–1105Google Scholar
  22. Popham EJ (1962) A repetition of Ege's experiments and a note on the efficiency of the physical gill of Notonecta (Hemiptera-Heteroptera). Proc Roy Ent Soc Lond (A) 37:154–160Google Scholar
  23. Pulliam HR (1975) Diet optimisation with nutrient constraints. Am Nat 109:765–768Google Scholar
  24. Pyke GH, Pulliam HR, Charnov EL (1977) Optimal foraging: a selective review of theory and tests. Q Rev Biol 52:137–154Google Scholar
  25. Rovama T (1970) Factors governing the hunting behaviour and selection of food by the great tit (Parus major L.). J Anim Ecol 39:619–668Google Scholar
  26. Sih A (1980) Optimal behaviour: can foragers balance two conflicting demands? Science 210:1041–1042Google Scholar
  27. Southwood TRE, Leston D (1959) Land and water bugs of the British Isles. Warne & Co. LondonGoogle Scholar
  28. Strangways-Dixon J (1961) The relationship between nutrition, hormones and reproduction in the blowfly Calliphora erythrocephala (Meig.).1. Selective feeding in relation to the reproductive cycle, the corpus allatum volume and fertilization. J Exp Biol 38:225–235Google Scholar
  29. Ware D (1973) Risk of epibenthic prey to predation by the rainbow trout (Salmo gairdneri). J Fish Res Bd Can 30:787–797Google Scholar
  30. Werner EE, Hall DJ (1974) Optimal foraging and the size selection of prey by the Bluegill Sunfish (Lepomis macrochirus). Ecology 55:1216–1232Google Scholar
  31. Werner EE, Mittleback GG (1981) Optimal foraging: field tests of diet choice and habitat switching. Amer Zool 21:813–829Google Scholar

Copyright information

© Springer-Verlag 1984

Authors and Affiliations

  • Barbara J. Cockrell
    • 1
  1. 1.Department of Zoology (Entomology)University of OxfordOxfordU.K.

Personalised recommendations