Lekking by Default: Female Habitat Preferences and Male Strategies in Uganda Kob

Abstract

JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org.. British Ecological Society is collaborating with JSTOR to digitize, preserve and extend access to Journal of Animal Ecology. Summary 1. In lek-breeding ungulates, males defend small territories clustered on traditional mating grounds called leks. One explanation for the evolution of lek-breeding is that males hold lek territories as a default strategy when they cannot monopolize females by defending female home ranges, stable female groups or predictable resource patches. 2. The assumptions of this explanation were tested by comparing the distribution of males, females and resources in a lekking antelope, the Uganda kob (Kobus kob thomasi) in Queen Elizabeth National Park, Uganda. Methods included repeated censuses along transects and multiple Poisson regression. 3. Female kob were associated strongly with short, green grass and more weakly with particular growth stages, vegetation communities and landforms. Female distribution varied widely over short periods of time and changes in density were associated with changes in grass greenness which apparently resulted from localized rainfall. 4. The distribution of adult males was not strongly related to that of females or of resources; most adult males were found within one kilometre of a lek. 5. The distribution of kob thus differs from that of puku (kobus vardoni), a closely related species in which females are consistently associated with swale vegetation and males hold territories based on patches of swale. These results are consistent with the argument that male kob advertise for females from display sites because no defensible resource patches exist which predictably attract non-oestrous females.

Uganda kob mating success does not increase on larger leks

“…The subspecies Uganda kob (K. kob thomasi Neumann 1886) has been extensively studied in Toro Game Reserve (Buechner 1961(Buechner , 1974Buechner and Schloeth 1965;Leuthold 1966) and in Queen Elizabeth National Park (Modha and Eltringham 1976;Balmford 1990;Balmford et al 1992Balmford et al , 1993Deutsch 1992Deutsch , 1994Deutsch and Nefdt 1992;Deutsch and Weeks 1992;Deutsch and Ofezu in press), both in the Western Rift Valley of southwestern Uganda. Females live in large, mixed-sex aggregations but move to clusters of 5-63 male mating territories when they become sexually receptive, and virtually all mating has been reported to take place on these leks (Leuthold 1966;Balmford 1990;Deutsch 1992). Females become receptive for about 24 h during a single oestrous cycle, and mate multiply with several males during this period (Buechner and Schloeth 1965).…”

“…Non-oestrous females also rest and ruminate on leks, which are in high visibility locations which may offer safety from predators (Deutsch and Weeks 1992). This study was carried out from March 1989 to June 1991, at which time there were 19 stable leks in Queen Elizabeth Park (Deutsch 1992), but kob movement between many of these was restricted by geographical barriers such as the Kazinga Channel and the Maramagambo Forest. Many of the data were therefore collected in the largest unbroken area of kob habitat, a 206-km a study area in the north of the park which supported about 14,700 kob utilizing 11 leks (Fig.…”

“…Many of the data were therefore collected in the largest unbroken area of kob habitat, a 206-km a study area in the north of the park which supported about 14,700 kob utilizing 11 leks (Fig. 1;Deutsch 1992).…”

“…Recent studies of lekking mammals have established some consensus concerning the first of these questions: males apparently hold lek territories as a default option when more common strategies such as the defense of female groups or resource patches are made impractical by the distribution of females and resources (Emlen and Oring 1977;Clutton-Brock 1989;Davies 1991;Clutton-Brock et al 1993;Deutsch 1994). Under these circumstances, males establish small territories based on display sites, and these may become clustered together if clustered territories either attract or retain females more efficiently than dispersed ones (Stillman et al 1993;Clutton-Brock et al 1993).…”

Territory establishment in lekking marine iguanas, Amblyrhynchus cristatus: support for the hotshot mechanism

“…One of the most interesting aspects of leks is the tight spatial clustering of males at specific sites. A number of not mutually exclusive hypotheses have been proposed to explain why males cluster their territories at specific places rather than occupy isolated non-resource based territories (Deutsch 1994;Höglund and Alatalo 1995). The hotspot model predicts that males congregate at areas of high female density (Bradbury and Gibson 1983;Bradbury et al 1986;Westcott 1997).…”