Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1016/S0304-3800(98)00180-X
Title (Primary) Intraspecific competition in a social spider
Author Ulbrich, K.; Henschel, J.R.
Source Titel Ecological Modelling
Year 1999
Department BZF
Volume 115
Issue 2-3
Page From 243
Page To 251
Language englisch
Abstract An individual-based model was developed to investigate the population dynamics of a permanently-social spider, Stegodyphus dumicola (Eresidae), in relation to intraspecific competition for food. This further develops our initial model that demonstrated that individual variability in body mass causes contest competition and is based on it. This confirmed field observations. In the present study, we examined whether intraspecific contest competition for food could be a mechanism for density regulation in S. dumicola. We investigated the consequences of contest competition on the individual variability in body mass as well as on the individual fitness of female spiders. Results demonstrate that colony size stabilises above a threshold of food level. At low food levels the risk of colony extinction is high because only few individuals survive and reproduce. Contest competition for food leads to high variance in body mass under conditions of food scarcity. Those variances tend to decrease with increasing food resources and a threshold of food level separates ranges of high and low variances. Model results indicate that individual females differ significantly by their fitness. An optimum of fitness was found at intermediate food levels. Results suggest that contest competition is a mechanism of density regulation in spider societies which stabilises colony size as well as variability in body mass and fitness.
Persistent UFZ Identifier https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=8458
Ulbrich, K., Henschel, J.R. (1999):
Intraspecific competition in a social spider
Ecol. Model. 115 (2-3), 243 - 251 10.1016/S0304-3800(98)00180-X