caa a22 4500 469060824 CHVBK 20180323132856.0 cr unu---uuuuu 170328e19920601xx s 000 0 eng 10.1007/BF01200563 doi (NATIONALLICENCE)springer-10.1007/BF01200563 A demonstration of asynchronous local cycles in an acarine predator-prey system [Elektronische Daten] [Gerrit van de Klashorst, J. Les Readshaw, Maurice Sabelis, Robert Lingeman] Population fluctuations in a continuous predator-prey system consisting of the spider mite,Tetranychus urticae Koch and its predator,Typhlodromus occidentalis Nesbitt, were assessed for almost 2 years (ca. 50 prey generations), on six mini-orchards of young apple trees in a climatically controlled glasshouse. During the first half of the experiment the plants were either ‘connected' to each other with dowel rods or ‘unconnected' and separate. In the second half, the plants were all ‘connected'. Population densities of both prey and predator on the unconnected mini-orchards were always higher than on the connected ones. Within the mini-orchards (=local scale), prey and predator populations go through a pattern of large amplitude cycles which continued throughout the experimental period. At the regional scale (mean over all mini-orchards) two types of fluctuations were observed. Large amplitude fluctuations associated with synchrony of the local cycles and small amplitude fluctuations associated with periods when local population cycles are proceeding out of phase. Transition from synchronous to asynchronous cycles took place very fast (within a few weeks), suggesting a mechanism generating asynchrony and possibly also partial refuges, which in turn trigger stabilising mechanisms at a regional scale. Causes of the synchrony are unclear. They may relate to the application of a pesticide (pirimicarb) used to control aphids, but there may just as well be an indirect form of causation, e.g. whereby the factors that promote aphid outbreaks also promote spider-mite population growth and temporary escape from control by the predators. Despite the synchronising factors the predator-prey system persisted, without external inputs, at a fairly small spatial scale, the size of a small glasshouse. Assessing the spatial scale and heterogeneity whereby decoupling of local cycles is sufficient for the cycles to proceed out of phase, remains an important area of experimental research. The experiment reported here provides some first clues and may form a standard for forthcoming experiments to assess the mechanisms promoting asynchrony, persistence and possibly also stability. Elsevier Science Publishers B.V., 1992 van de Klashorst Gerrit Zoology Department, Australian National University, Canberra, A.C.T., Australia aut Les Readshaw J. Division of Entomology, CSIRO, Canberra, A.C.T., Australia aut Sabelis Maurice Department of Pure and Applied Ecology, Section Population Biology, University of Amsterdam, Kruislaan 302, 1098 SM, Amsterdam, Netherlands aut Lingeman Robert Department of Pure and Applied Ecology, Section Population Biology, University of Amsterdam, Kruislaan 302, 1098 SM, Amsterdam, Netherlands aut Experimental & Applied Acarology Kluwer Academic Publishers 14/3-4(1992-06-01), 185-199 0168-8162 14:3-4<185 1992 14 10493 https://doi.org/10.1007/BF01200563 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF01200563 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- van de Klashorst Gerrit Zoology Department, Australian National University, Canberra, A.C.T., Australia aut NATIONALLICENCE 700 1- Les Readshaw J. Division of Entomology, CSIRO, Canberra, A.C.T., Australia aut NATIONALLICENCE 700 1- Sabelis Maurice Department of Pure and Applied Ecology, Section Population Biology, University of Amsterdam, Kruislaan 302, 1098 SM, Amsterdam, Netherlands aut NATIONALLICENCE 700 1- Lingeman Robert Department of Pure and Applied Ecology, Section Population Biology, University of Amsterdam, Kruislaan 302, 1098 SM, Amsterdam, Netherlands aut NATIONALLICENCE 773 0- Experimental & Applied Acarology Kluwer Academic Publishers 14/3-4(1992-06-01), 185-199 0168-8162 14:3-4<185 1992 14 10493 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer