Jump to main content.

Markov Chain Nest Productivity Model (MCnest)

You will need the free Adobe Acrobat Reader to view some of the files on this page.
See EPA's PDF page to learn more about PDF, and for a link to the free Adobe Acrobat Reader.

The Markov Chain Nest Productivity Model (or MCnest) integrates existing toxicity information from three standardized avian toxicity tests with information on species life history and the timing of pesticide applications relative to the timing of avian breeding seasons, to quantitatively estimate the impact of pesticide-use scenarios on the annual reproductive success of bird populations. MCnest provides risk assessors with a tool to go beyond the current screening-level quotient method approaches for assessing reproductive effects by estimating the proportional change in reproductive success. MCnest translates toxicity information into the currency needed for conducting a population-level assessment of pesticide risks.

The User’s Manual (PDF) (41 pp, 1.4 MB) provides users with an introduction and examples of all the features of the MCnest model. The Technical Manual (PDF) (90 pp, 644 KB) provides risk assessors with background on how the model functions and the scientific basis for its approach to estimating changes to reproductive success. It is intended to help users of MCnest to understand the strengths and limitations of the model and to effectively interpret the results of MCnest simulations. The Species Life History Profiles (PDF) (197 pp, 1,199 KB) provide background information and rationale for selecting the default life history characteristics for a suite of avian species.

The basic version of MCnest consists of the following two self-extracting zip files as well as the Matlab Compiler Runtime (see instructions below for how to download this file from the Mathworks website).  Note that the two files below must be saved to the same directory on your computer.

MCnest was designed in Matlab R2012a and requires the Matlab Compiler Runtime (MCR) to be installed on your computer.  MCnest will not run without the MCR.  Due to its size, we are not hosting the MCR on our website.  It can be downloaded free of charge from the Mathworks website.  The required version is the Windows 32-bit MCR for Matlab release 2012a.

For a list of recent changes and bug fixes see the MCnest revision history. (PDF) (1 pp, 16 KB)
See the list of species library releases. (PDF) (1 pp, 5 KB)

Background references:

Bennett, R.S. and M.A. Etterson. 2013. On selecting surrogate endpoints for estimating pesticide effects on avian reproductive success. Integrated Environmental Assessment and Management 9:600-609.

Etterson, M.A. and R.S. Bennett, R.S. 2013. Quantifying the effects of pesticide exposure on annual reproductive success of birds. Integrated Environmental Assessment and Management 9:590-599.

Etterson, M. A., S. N. Ellis-Felege, D. Evers, G. Gauthier, J. A. Grzybowski, B. J. Mattsson, L. R. Nagy, B. J. Olsen, C. M. Pease, M. P. van der Burg, and A. Potvien. 2011. Modeling fecundity in birds:  Conceptual overview, current models, and considerations for future developments. Ecological Modelling 222: 2178-2190.

Etterson, M. A., R. S. Bennett, E. L. Kershner, and J. W. Walk.  2009.  Markov chain estimation of avian seasonal fecundity.  Ecological Applications  19(3): 622-630.

Bennett, R. S. and M. A. Etterson.  2007.  Incorporating results of avian toxicity tests into a model of annual reproductive success.  Integrated Environmental Assessment and Management  3(4): 498-507.

Bennett, R. S. and M. A. Etterson.  2006.  Estimating pesticide effects on fecundity rates of wild birds using current laboratory reproduction tests.  Human and Ecological Risk Assessment 12(4): 762-781.

Etterson, M. A. and R. S. Bennett.  2006.  On the use of published demographic data for population-level risk assessment in birds.  Human and Ecological Risk Assessment 12(6):1074-1093.

Bennett, R. S., I. C. Dewhurst, A. Fairbrother, A. D. M. Hart, M. J. Hooper, A. Leopold, P. Mineau, S. R. Mortensen, R. F. Shore, and T. A. Springer.  2005.  A new interpretation of avian and mammalian reproduction toxicity test data in ecological risk assessment.  Ecotoxicology 14(8): 801-815.

For further information, please contact Matt Etterson etterson.matthew@epa.gov, (218) 529-5158.

Local Navigation

Jump to main content.