The many faces of population density.
Oecologia
; 145(2): 276-81, 2005 Sep.
Article
en En
| MEDLINE
| ID: mdl-16001227
ABSTRACT
Population density, one of the most fundamental demographic attributes, may vary systematically with spatial scale, but this scale-sensitivity is incompletely understood. We used a novel approach-based on fully censused and mapped distributions of eastern grey squirrel (Sciurus carolinensis) dreys, beaver (Castor canadensis) lodges, and moose (Alces alces)--to explore the scale-dependence of population density and its relationship to landscape features. We identified population units at several scales, both objectively, using cluster analysis, and arbitrarily, using artificial bounds centred on high-abundance sites. Densities declined with census area. For dreys, this relationship was stronger in objective versus arbitrary population units. Drey density was inconsistently related to patch area, a relationship that was positive for all patches but negative when non-occupied patches were excluded. Drey density was negatively related to the proportion of green-space and positively related to the density of buildings or roads, relationships that were accentuated at coarser scales. Mean drey densities were more sensitive to scale when calculated as organism-weighted versus area-weighted averages. Greater understanding of these scaling effects is required to facilitate comparisons of population density across studies.
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Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Roedores
/
Sciuridae
/
Ciervos
/
Ecosistema
Límite:
Animals
Idioma:
En
Revista:
Oecologia
Año:
2005
Tipo del documento:
Article
País de afiliación:
Canadá