P. S. Petraitis and S. R. Dudgeon. 2015. Variation in recruitment and the establishment of alternative community states. Ecology 96:31863196. http://dx.doi.org/10.1890/14-2107.1


R script and data file to run cusp analysis presented in Tables A4 and A5.
Ecological Archives E096-274-S4.


File list (downloads)


P. S. Petraitis
Department of Biology
University of Pennsylvania
Philadelphia, PA 19104-6018, USA
E-mail: [email protected]

S. R. Dudgeon
Department of Biology
California State University
Northridge, CA 91330-8303, USA
E-mail: [email protected]

File list

S4_Recruit_cusp.R (MD5: 580d2455a8982fd087643b6feaa0ce1c)

S4_Cusp_data.csv (MD5: e99f1a6c2f4e4e3bbf3a872a8adea00e)


S4_Recruit_cusp.R is R code to run seven competing models to fit percent cover by rockweeds, mussels, and barnacles as a cusp catastrophe. Models used different combinations of recruitment rates are used as parameters. The package allows the parameters and the ecosystem state to be defined as linear functions of several variables, and finds the coefficients of these functions that provide the best fit.

S4_Cusp_data.csv is the data file needed to run R script. Ecosystem state data are from Petraitis et al. (2008; Ecological Archives E089-032) and include understory cover by barnacles and mussels and canopy cover by Ascophyllum and Fucus. Recruitment data are from data file S3_Recruit_1997-2008_R_ready.csv in Supplement 3. Note file has 59 lines of data; site MD for S2 was dropped because of missing data for cover.

Suppl 4 table