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POLYETHISM IN FORAGING IN A POLYMORPHIC PREDATOR, ENOPLOGNATHA OVATA (ARANEAE: THERIDIIDAE): A CASE FOR BALANCE

Published online by Cambridge University Press:  31 May 2012

Carlos F. Greco  and
Peter G. Kevan
Carlos F. Greco
Affiliation:
Department of Environmental Biology, University of Guelph, Guelph, Ontario, Canada N1G 2W1
Peter G. Kevan*
Affiliation:
Department of Environmental Biology, University of Guelph, Guelph, Ontario, Canada N1G 2W1
*
2Author to whom all correspondence should be addressed.
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Abstract

Two colour morphs of Enoplognatha ovata (Clerck), “redimita” and “lineata” the abdomens of which are whitish with two pink stripes and greyish-yellow, respectively, differ in their foraging strategies. When placed in artificial arenas with flowering stems to ascend, we noted that both morphs had a strong tendency to wander over the ground rather than ascend a stem [unlike the crab spider, Misumena vatia Clerck (Araneae: Thomisidae)], but that lineata was significantly more prone to wander than was redimita. Neither morph showed choice for the type of stem or colour of flower. Nevertheless, redimita showed a greater preference for choosing white artificial flowers (discs) atop 30-cm wooden rods than did lineata. We propose that the relative abundances of the two colour morphs in the natural population represents a balanced polymorphism which is maintained in part by polyethism in hunting strategies, with redimita being more fastidious in its selection of cryptic hunting sites in flowers than is lineata, and the latter being more cryptic and more errant on the ground.

Résumé

Deux formes de colorations différentes d’Enoplognatha ovata (Clerck), «redimita» et «lineata», la première à l’abdomen blanc portant deux rayures roses, la seconde à l’abdomen jaune grisâtre, diffèrent aussi par leur stratégie de quête de nourriture. En présence de tiges à inflorescences pour grimper, dans des arènes artificielles, nous avons constaté que les deux formes ont fortement tendance à errer sur le sol plutôt qu’à grimper [contrairement à l’araignée crabe Misumena vatia Clerck (Araneae : Thomisidae)], et que lineata est significativement plus encline à errer que redimita. Ni l’une ni l’autre forme n’ont manifesté de préférence pour une couleur de fleur ou un type de tige en particulier. Cependant, les araignées de la forme redimita ont montré une préférence plus grande à choisir des fleurs artificielles blanches (disques) au bout de tiges de bois de 30 cm que celles de la forme lineata. Nous croyons que les abondances relatives des deux formes dans la population naturelle représentent un polymorphisme d’équilibre maintenu en partie par le polyéthisme des stratégies de chasse : redimita est un chasseur plus pointilleux dans son choix de sites de chasse dissimulés dans les fleurs, alors que la forme lineata a plus tendance à se cacher et est plus encline à errer sur le sol.

[Traduit par la Rédaction]

Type
Articles
Information
The Canadian Entomologist , Volume 131 , Issue 2 , April 1999 , pp. 259 - 268
Copyright
Copyright © Entomological Society of Canada 1999

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References

Bristowe, W.S. 1958. The Word of Spiders. London: Collins.Google Scholar
Caraco, T. 1980. On foraging time allocation in a stochastic environment. Ecology 61: 119–28.CrossRefGoogle Scholar
Caraco, T., Gillespie, R.G. 1986. Risk-sensitivity: foraging mode in an ambush predator. Ecology 67: 1180–85.Google Scholar
Freitag, R., Barnes, B.L., Leech, R.E., Tropea, R. 1982. An annotated list of spiders collected during the big dig near Wawa, Ontario, 1971. Canadian Field-Naturalist 96: 383–88.Google Scholar
Greco, C.F., Kevan, P.G. 1994. Contrasting patch choosing by anthophilous ambush predators: vegetation and floral cues for decisions by a crab spider (Misumena vatia) and males and females of an ambush bug (Phymata americana). Canadian Journal of Zoology 72: 1580–88.Google Scholar
Greco, C.F., Kevan, P.G. 1995. Patch-choice in the anthophilous ambush predator Phymata americana: improvement by switching hunting sites. Canadian Journal of Zoology 73: 1912–17.CrossRefGoogle Scholar
Greco, C.F., Weeks, P., Kevan, P.G. 1995. Patch choice in ambush predators: plant height selection by Misumena vatia (Araneae, Thomisidae) and Phymata americana (Heteroptera, Phymatidae). Ecoscience 2: 203–5.Google Scholar
Huey, R.B., Pianka, E.R. 1981. Ecological consequences of foraging mode. Ecology 62: 991–99.Google Scholar
Hippa, H., Oksala, I. 1981. Polymorphism and reproductive strategies of Enoplognatha ovata (Clerck) (Araneae, Theridiidae) in Northern Europe. Annales Zoologici Fennici 18: 179–90.Google Scholar
Janetos, A.C. 1982. Active foragers vs. sit-and-wait predators: a simple model. Journal of Theoretical Biology 95: 381–85.Google Scholar
Levi, H.W. 1957. The spider genera Enoplognatha, Theridion, and Paidisca in America north of Mexico. Bulletin of the American Museum of Natural History 1112(1): 1–123.Google Scholar
Morse, D. 1983. Foraging patterns and time budgets of the crab spider Xysticus emertoni Keyserling and Misumena vatia Clerck (Araneae, Thomisidae) on flowers. Journal of Arachnology 11: 87–94.Google Scholar
Morse, D. 1993. Some determinants of dispersal by crab spiders. Ecology 74: 427–32.Google Scholar
Morse, D., Fritz, R.S. 1982. Experimental and observational studies of patch-choice at three scales by the crab spider Misumena vatia. Ecology 63: 172–82.Google Scholar
Nielsen, E. 1932. The biology of spiders with special reference to the Danish fauna. Vol. I. Levin and Munnksgaard, Copenhagen.Google Scholar
Norberg, R.A. 1977. An ecological theory on foraging time and energetics and choice of optimal food-searching method. Journal of Animal Ecology 46: 511–29.Google Scholar
Oxford, G.S. 1983. Genetics of colour and its regulation during development in the spider Enoplognatha ovata (Clerck) (Araneae, Theridiidae). Heredity 51: 621–34.CrossRefGoogle Scholar
Oxford, G.S. 1985. A countrywide survey of colour morph frequencies in the spider Enoplognatha ovata (Clerck) (Araneae, Theridiidae): evidence for natural selection. Biological Journal of the Linnean Society 24: 103–42.CrossRefGoogle Scholar
Oxford, G.S. 1989. Genetics and distribution of black spotting in Enoplognatha ovata (Araneae, Theridiidae) and the role of intermittent drift in population differentiation. Biological Journal of the Linnean Society 35: 111–28.Google Scholar
Oxford, G.S. 1991. Visible morph-frequency variation in allopatric and sympatric populations of two species of Enoplognatha (Araneae, Theridiidae). Heredity 67: 317–24.Google Scholar
Pianka, E.R. 1966. Convexity, desert lizards and spatial heterogeneity. Ecology 47: 1055–59.Google Scholar
Pyke, G.H. 1984. Optimal foraging theory: a critical review. Annual Review of Ecology and Systematics 15: 523–75.Google Scholar
Real, L. 1980. Fitness, uncertainty and the role of diversification in evolution and behaviour. American Naturalist 115: 623–38.Google Scholar
Reillo, P.R. 1989. Color polymorphism in the spider Enoplognatha ovata (Araneae, Theridiidae), broad-scale morph-frequency variation in Northeastern North America. American Midland Naturalist 122: 199–03.Google Scholar
Reillo, P.R., Wise, D.H. 1988 a. Genetics of color expression in the spider Enoplognatha ovata (Araneae, Theridiidae) from coastal Maine. American Midland Naturalist 119: 318–26.Google Scholar
Reillo, P.R., Wise, D.H. 1988 b. An experimental evaluation of selection on colour morphs of the polymorphic spider Enoplognatha ovata (Araneae, Theridiidae). Evolution 42: 1172–89.Google Scholar
Schoener, T.W. 1971. Theory of feeding strategies. Annual Review of Ecology and Systematics 2: 369–404.CrossRefGoogle Scholar
Seligy, V.L. 1969. Post-embryonic development of the spider Enoplognatha ovata (Clerck) (Araneae, Therediidae). Zoological Journal of the Linnean Society 50: 21–31.CrossRefGoogle Scholar
Sih, A. 1980. Optimal behavior: can foragers balance two conflicting demands? Science (Washington, D.C.) 210: 1041–42.Google Scholar
Stephens, D.W., Charnov, E.L. 1982. Optimal foraging: some simple stochastic models. Behavioral Ecology and Sociobiology 10: 251–63.Google Scholar
Wise, D.H., Reillo, P.R. 1985. Frequencies of color morphs in four populations of E. ovata (Araneae, Theriididae) in Eastern North America. Psyche 92: 135–44.Google Scholar