thumbnail

Consumers limit the abundance and dynamics of a perennial shrub with a seed bank

American Naturalist

By:
,
DOI: 10.1086/507877

Links

Abstract

For nearly 30 years, ecologists have argued that predators of seeds and seedlings seldom have population-level effects on plants with persistent seed banks and density-dependent seedling survival. We parameterized stage-based population models that incorporated density dependence and seed dormancy with data from a 5.5-year experiment that quantified how granivorous mice and herbivorous voles influence bush lupine (Lupinus arboreus) demography. We asked how seed dormancy and density-dependent seedling survival mediate the impacts of these consumers in dune and grassland habitats. In dune habitat, mice reduced analytical ?? (the intrinsic rate of population growth) by 39%, the equilibrium number of above-ground plants by 90%, and the seed bank by 98%; voles had minimal effects. In adjacent grasslands, mice had minimal effects, but seedling herbivory by voles reduced analytical ?? by 15% and reduced both the equilibrium number of aboveground plants and dormant seeds by 63%. A bootstrap analysis demonstrated that these consumer effects were robust to parameter uncertainty. Our results demonstrate that the quantitative strengths of seed dormancy and density-dependent seedling survival-not their mere existence-critically mediate consumer effects. This study suggests that plant population dynamics and distribution may be more strongly influenced by consumers of seeds and seedlings than is currently recognized. ?? 2006 by The University of Chicago.

Additional Publication Details

Publication type:
Article
Publication Subtype:
Journal Article
Title:
Consumers limit the abundance and dynamics of a perennial shrub with a seed bank
Series title:
American Naturalist
DOI:
10.1086/507877
Volume
168
Issue:
4
Year Published:
2006
Language:
English
Larger Work Type:
Article
Larger Work Subtype:
Journal Article
Larger Work Title:
American Naturalist
First page:
454
Last page:
470
Number of Pages:
17