Rachel M. Quinn

Abundance–range size relationships of macrolepidoptera in Britain: the effects of taxonomy and life history variables

1. A positive relationship between the local abundances and regional distributions of species in an assemblage has been observed for a wide variety of taxa, but its underlying mechanisms remain poorly understood.

Coincidence between consumer and host occurrence: macrolepidoptera in Britain

1. The interspecific relationship between the distributions of consumers and resources is examined, using data for macrolepidoptera (moths) in Britain.

The biogeography of scarce vascular plants in Britain with respect to habitat preference, dispersal ability and reproductive biology

Abstract We investigated the effect of five plant and habitat characteristics on the national distribution of scarce British plants defined as those occurring in 16–50 10 × 10 km squares (‘loci’). In all 139 species considered, loci were more aggregated than expected by chance. Habitat, dispersal ability and pollination type were significantly correlated with pattern of locus distribution. Seed size and life history were unrelated to the degree of aggregation of loci. The most important result from a conservation perspective is the tendency for plants with poor dispersal ability to have more aggregated distributions (i.e. they have loci closer together) than plants with good dispersal ability. One implication of this result may be that re-introduction or translocation could be useful techniques for supplementing natural dispersal in the management of such species.

Relative measures of geographic range size: empirical comparisons

Many different measures of range size are used for both empirical and conservation purposes. The possible consequences of the particular methods used in determining observed patterns of results are seldom considered. Using species of butterflies and freshwater molluses in Britain, we investigate the relationship between the range sizes measured by nine different methods and the sets of rare species they distinguish. A comparison of range sizes measured at different scales. Britain and Europe, is also made for the butterflies. We find that for many studies involving range size the various measures of range size are interchangeable. With respect to the identification of rare species the results are not as clear.