Authors
Sean C Anderson, Andrew B Cooper, Nicholas K Dulvy
Publication date
2013/10
Journal
Methods in Ecology and Evolution
Volume
4
Issue
10
Pages
971-981
Description
- A financial portfolio metaphor is often used to describe how population diversity can increase temporal stability of a group of populations. The portfolio effect (PE) refers to the stabilizing effect from a population acting as a group or ‘portfolio’ of diverse subpopulations instead of a single homogeneous population or ‘asset’. A widely used measure of the PE (the average‐CV PE) implicitly assumes that the slope (z) of a log–log plot of mean temporal abundance and variance (Taylor's power law) equals two.
- Existing theory suggests an additional unexplored empirical PE that accounts for z, the mean–variance PE. We use a theoretical and empirical approach to explore the strength and drivers of the PE for metapopulations when we account for Taylor's power law compared with when we do not. Our empirical comparison uses data from 51 metapopulations and 1070 subpopulations across salmon, moths and reef …
Scholar articles
SC Anderson, AB Cooper, NK Dulvy - Methods in Ecology and Evolution, 2013