Red-cockaded Woodpecker Recovery
Conserving the Nature of America

The RCW-IBM model

Model Description

A spatially-explicit, individual-based model of red-cockaded woodpecker population dynamics has been developed by Larry Crowder, Jeffery Priddy and Jeff Walters, and is available to the RCW community on a contractual basis under the conditions described below. The model projects population size and distribution through time by tracking each individual bird and individual territory. The model is parameterized in terms of age- and sex-specific mortality, reproduction and dispersal behavior, and thus population behavior is the outcome of the fates of all the individuals in the population. Model output includes expected population size over time, population structure (i.e., group size, number of helpers, number of solitary males, etc…) and relative probability of abandonment of each individual territory. The relative probability of occupation of recruitment clusters at particular locations can also be examined with the model.


The user must provide the locations of woodpecker groups and recruitment clusters, one point to represent the center of each. This list of locations must be a computer file, either plain text, Excel spreadsheet or ArcView point theme. Optionally, the user can provide ArcView polygon themes or georeferenced bitmaps to represent snapshots of habitat quality through time. The user can also provide an ArcView project of their study area to display model results in geographic context.


The model is available through contracts with the Duke University Marine Laboratory (DUML) where Crowder and Priddy, and the RCW-IBM, reside. Contracts will include a subcontract with Virginia Tech (VT) where Walters resides, to support his involvement with each project. Costs are as follows:

1. Small projects: $6,500 ($4,500 for modeling time, $500 supplies, $500 travel + writing, $1,000 subcontract VT for writing and travel). Most projects with RCW populations under 100 groups would qualify as a small project.

2. Large projects: $13,000 ($9,000 for modeling time, $1,000 supplies, $1,000 travel + writing, $2,000 subcontract VT for writing and travel)

3. Short course: $5,000 for training project short course for qualified model user ($4,000 for modeling time, including user time with Jeffery Priddy, $500 supplies). This option would involve sending someone to the DUML to learn how to run the model. Trainee must be highly computer literate, skilled in computerized analysis, and preferably familiar with ArcView. The trainee would take an executable copy of the model with them and continue to work with it on their own, with e-mail support services from Jeffery Priddy at DUML for the duration of the contract.

Project cost will be determined based on the number and nature of runs requested, and large and small represent the extremes - projects in between would cost something in between. These costs do not include development of new model capabilities.

Contact information

To discuss possible modeling contracts, contact Larry Crowder at the Duke Marine Laboratory (; 252-504-7637) or Jeff Walters at Virginia Tech (; 540-231-3847).

Last Updated: March 28, 2014