FAO Home>Fisheries & Aquaculture
FAO of the UN

P. Fréon, C. Mullon and G. Pichon
213 rue Lafayette
75480 Paris Cedex 10, France

System Requirements.

MS-DOS 3 and over; MS-Windows 3 or Windows95 and over + EXCEL4 and over for the 2.0 version.
Disk space: 2 mega bytes
RAM : 0.5 mega bytes
Video card: any


Stock assessment by surplus production models incorporating an environmental variable

Various equations allowing for the introduction of an environmental variable into surplus production models are available. CLIMPROD helps the user to select the model corresponding to a particular case according to objective criteria. It looks like a simple expert-system and uses artificial intelligence to converse with the user. The basic inputs are annual data-series on catch (Y) and effort (E) of a fishery on a single stock, and annual (or seasonal) data-series on an environmental variable (V) known to influence the abundance or the catchability of this stock. At least 12 years observation are required, or more in non-equilibrium (transition) situations.

The software provides a statistical and graphical description of the data-set and then allows for choice of an appropriate model, fitting it and trying to assess the fit with parametric and non-parametric tests before presenting tables and graphs of the results.

CLIMPROD can also be used for fitting the three conventional production models (linear, exponential, generalised) without environmental influence or, conversely, for fitting the relationship between environment and production without the influence of fishing effort. In both cases, non-parametric tests and graphical facilities are available.

Improvements in Version 2.0.

The software was first designed under MS-DOS (version 1.0) and did not allow for convenient printing of graphics. The new version is still in DOS but an EXCEL interface has been added. An XL macro allows for fast and friendly re-plotting and editing of the plots and tables seen during the DOS session.

A minor bug existed in the 1.0 version (only for past-averaging effort in conventional surplus production models, not in the other models). This bug has been removed in the 2.0 version.


A short manual is available for the 1.0 version. It is subdivided in two parts: a reference guide and a user guide. There is no manual for the 2.0 version but on-line help is available.

A Recommendation.

This software is mentioned in a recent book (Computers in Fisheries Research, by B.A. Megrey and E. Moksness, 1996, Chapman & Hall) on half a page. It is said: 'CLIMPROD is an excellent example of an expert system embedded within a comprehensive computational model and data'.

Statistics and Information Branch (FIAS)

Fisheries and Aquaculture Department
Food and Agriculture Organization of the United Nations
Viale delle Terme di Caracalla

Email: Fish-Statistics-Inquiries

Powered by FIGIS