Ecological Archives E090-048-A5

Jebediah F. Brodie, Olga E. Helmy, Warren Y. Brockelman, and John L. Maron. 2009. Functional differences within a guild of tropical mammalian frugivores. Ecology 90:688–698.

Appendix E. Sensitivity of Choerospondias axillaris population growth rate (for all disperser species combined) to demographic vital rates.

We assessed sensitivity using both analytical elasticity analysis (Caswell 2001) and life-stage simulation analysis ("LSA"; Wisdom et al. 2000). The latter accounts for both the ability of infinitesimal changes in each vital rate to affect population growth (analytical elasticity) and the range of variability of the vital rates. For each of 1000 iterations we randomly chose vital rates from uniform distributions bounded by their upper and lower 95% bootstrap confidence limits, constructed projection matrices, and calculated λ. We then performed simple linear regressions of vital-rates values vs. λ. The R2 value of each regression (rescaled so that the total summed to 1) was a measure of the sensitivity of λ to each vital rate.

FigE1
 
   FIG. E1. Sensitivity of Choerospondias axillaris population growth rate (for all disperser species combined) to demographic vital rates.

 

LITERATURE CITED

Caswell, H. 2001. Matrix population models. Second edition. Sinauer Associates, Sunderland, Massachusetts, USA.

Wisdom, M. J ., L. S. Mills, and D. F. Doak. 2000. Life-stage simulation analysis: estimating vital rate effects on population growth for species conservation. Ecology 81:628–641.


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