Resource Defence or Exploded Lek? – A Question of Perspective

Mating systems involving male territorial defence are usually characterized based on categorical characteristics (Emlen & Oring 1977), for instance the number of mates per male or per female, the presence of resources within territories, the spatial distribution of neighbouring territories, whether male territories include female territories and how many, or the purpose of female visits at territories (see Shuster & Wade 2003). In leks, the purpose of female visits seems to be clear, as a lek is defined as ‘aggregated male display that females attend primarily for the purpose of fertilization’ (Höglund & Alatalo 1995). In exploded leks, male territories within such aggregations are fairly large, and sometimes may contain resources used by females (Emlen & Oring 1977). Resource-based leks differ from exploded leks in that they contain resources that are critical for females and males display close to or at these critical resources (Jiguet 2002). Finally, in resourcedefence mating systems, males control the access to critical resources that females require for reproduction (Emlen & Oring 1977). Although these categories seem well defined, it is not always straightforward to classify a certain mating system of interest as they often include characteristics of different categories. When males set up territories in which females may feed or even breed, a mating system would still be classified as an exploded lek, if the resources present Correspondence Alexander Kotrschal, Behavioural Ecology, Institute of Ecology and Evolution, University of Bern, Wohlenstrasse 50a, 3032 Hinterkappelen, Switzerland. E-mail: [email protected]