Documents for Gulf sturgeon meeting 2010

Gulf Sturgeon Recovery plan

5-year Gulf Sturgeon Status Review



Gulf Sturgeon Stock Assessment (as presented and discussed at the meeting November 2009)

Gulf Sturgeon Stock Assessment Files (zip file containing data and example ADMB code)


"Sturgeon" PVA model

Here is a simple PVA model that runs in visual basic that Carl Walters built based on a conversation with Phil Kirk. Should be of interest to many of you working with Gulf sturgeon and other sturgeon species (or really any fish species).  The model is individual based and uses a Beverton-Holt stock recruitment relationship to predict number of age 1 recruits.   Compensatory survival improvement is represented by the Goodyear "compensation ratio" (of maximum juvenile survival rate at low abundance to juvenile survival rate at natural population abundance) which is likely pretty low (2-10) for sturgeon species. You can also vary size at maturity, fecundity per body weight of mature fish, skip-spawning interval (which according to this model has big effect on extinction risk for very low populations), and log-normal variation in survival to age 1 (most fish show such variation).

To run the model, you need to

(1) download the zip file here

(2) unzip the two files to a folder (can be on your desktop);

(3) copy the file inside the folder called mtrandom.dll and paste it anywhere in your windows/system32 folder (generally use MyComputer to navigate to your "c" drive, then open you Windows folder, have it show all files, then open the system32 folder and paste the mtrandom.dll file there; then close all of these folders

(4) Go back to the folder you unzipped and click on the PVA.exe file icon to run the program.