Density-Dependent Clutch Size Caused by Habitat Heterogeneity

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 some studies but not in others the average clutch size decreases with density. 2. We propose that density-dependent fecundity occurs because, as density increases, proportionally more poor-quality sites (with small clutches) are occupied, and not because the clutch size in all territories decreases. This mechanism will only cause density dependence if the habitat is heterogeneous at the scale of the home range or territory of an individual. 3. Density-dependent fecundity will be found in some populations but not in others because of differences in the scale of habitat heterogeneity. 4. Results from an experimental study on tits (Parus sp.) support the hypothesis.

Evolutionary conservation advice for despotic populations: habitat heterogeneity favours conflict and reduces productivity in Seychelles magpie robins

“…The ideal despotic model, phrased in its original way or its various alter egos such as 'site-dependent population regulation' (Rodenhouse et al 1997) or the 'habitat heterogeneity hypothesis' (Dhondt et al 1992), has fuelled a rich body of empirical studies on the nature of density-dependent settlement in heterogeneous habitats, both in birds (Ferrer & Donázar 1996;Krü ger & Lindströ m 2001;Kokko et al 2004;Carrete et al 2006;Burgess et al 2008) and other animals (Levin et al 2000;Calsbeek & Sinervo 2002;Morris et al 2004;Bauer et al 2005). Throughout the literature, a strong emphasis is put on distinguishing between despotic regulation and patterns expected from interference versions of the IFD (Ferrer et al 2006).…”

Avian Life History Evolution in Relation to Nest Sites, Nest Predation, and Food

“…In contrast, evidence supporting density-dependence as the cause of the inverse correlation between fecundity and survival is more tenuous. Increased density can cause reductions in both adult survival and clutch size (e.g., Perrins 1965, Ekman 1984, Arcese and Smith 1988, Dhondt et a!. 1992) and such density-dependent effects cause a positive correlation between fecundity and adult survival rather than the negative one observed.…”

A process of pair formation leading to assortative mating: passive age-assortative mating by habitat heterogeneity

“…Age of mates is often correlated with territory quality, with immature birds usually occupying lowquality territories (Newton et al 1981;Steenhof et al 1983). Furthermore, territory quality is one of the main factors affecting reproductive success, especially at the population level in high-density situations (Dhondt et al 1992;Ferrer & Doná zar 1996). Although habitat heterogeneity in natural landscapes has often been emphasized (Wiens 1976;Turner 1989;Kotliar & Wiens 1990;Rodenhouse et al 1997Rodenhouse et al , 1999), few studies have tested how different turnover rates between territories (e.g.…”