Abstract

AimOne of the few general laws in ecology is that species richness is a positive function of area. However, it has been proposed that area would merely be a proxy for energy. Additionally, habitat heterogeneity has been found to be an important factor determining species richness. Yet the relative importance of those relationships is little known, and it is still unclear how they are brought about. We aimed to dissect which factors drive the species richness of boreal forest birds, and to identify the most probable mechanisms.LocationForested protected areas in Finland.MethodsUsing bird line census data collected in 104 protected areas, we ran simultaneous autoregressive models to explain the species richness of forest birds. We explored the value of forest area, tree volume, tree growth, mean degree days and habitat heterogeneity as explanatory variables and used the species richness within different species groups, based on the predictions of hypothesized mechanisms, as a response variable.ResultsEnergy, rather than area or habitat heterogeneity, seems to be the main driver of species richness in boreal forest birds. More specifically, productive energy was a better predictor of total species richness than solar energy. Among the tested hypothetical mechanisms, the sampling hypothesis received strong support. After accounting for sampling, solar energy had an effect on species richness.Main conclusionsAs productive energy, such as tree volume, is associated with species richness, high-energy areas should be prioritized in forest conservation planning. Reductions in productive energy may first lead to the disappearance of the rarest species due to the random sampling process. Climate change may result in increased species richness due to increasing amount of productive and solar energy in forests. However, the range shifts of bird species may not be fast enough to keep up with the temperature increases.

Keywords

Birds; Finland; habitat heterogeneity; productive energy; solar energy; species-area relationship; species-energy relationship; species number

Published in

Global Ecology and Biogeography
2010, Volume: 19, number: 1, pages: 61-71
Publisher: WILEY-BLACKWELL

SLU Authors

• Roberge, Jean-Michel

  • Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences
    
  • University of Jyväskylä

Sustainable Development Goals

SDG15 Protect, restore and promote sustainable use of terrestrial ecosystems, sustainably manage forests, combat desertification, and halt and reverse land degradation and halt biodiversity loss
SDG13 Take urgent action to combat climate change and its impacts


UKÄ Subject classification

Forest Science
Physical Geography
Ecology


Publication identifier

DOI: https://doi.org/10.1111/j.1466-8238.2009.00491.x

Permanent link to this page (URI)

https://res.slu.se/id/publ/60183