A broad plan covering the need for all types of statistical data from resources studies to socio-economics and planning should be prepared. Five stages may be recognized in the compilation of fishery data:
(i) transfer of primary data on field sheets to summary sheets, or in the case of computer records, punching the data onto cards or directly onto discs or tapes;
(ii) checking the basic data for errors of transfer and gross recording errors (in the case of computer punched data, this can in part be done by appropriate automatic checking routines);
(iii) weighting up samples to total landings by day, port, month and region as needed and preparation of summaries of data by different sub-categories (e.g., catch and effort separately by gear type, area, species, time or any combination of them). Here, the great advantage of computerization lies - rounding and other errors are minimized, as well as much time and effort saved;
(iv) analysis of the data to provide conclusions as to (e.g.,) the state of the resources, total exports of fish etc. Some time and thought should also be devoted at an early date to the likely needs for future data analyses, even if personnel are not yet available to make full use of it.
(v) filing and retrieval of data on a way that allows it to be easily retrievable and revised. The use of a large-scale map of the sampling frame, cross referenced to the appropriate file in the storage cabinets, allows them to be updated as new information becomes available. Files should be kept for each landing point, listed and categorized, and separate, but cross-referenced files, should be kept also on the principal fish species landed, and on the main fishing grounds/stocks.
This publication has not developed at great length on the technical aspects of calculation, magnitudes/variances etc, which can be more readily obtained from a standard text book (e.g. Steel and Torrie, 1960), but a brief summary of some of the key concepts is provided in Appendix 4.
The use of a microcomputer for summarizing and analysing data forecasts has advantages for even moderate-sized fisheries departments. The priority in small departments is, however, for actually collecting data, and time spent on learning to operate and use these computer facilities cannot be allowed to detract from this primary function. This kind of equipment can therefore only be justified if it frees individuals from clerical work to actually go in the field and collect data. The advantages here of having some regional organizations whose responsibility is preparing regular data and summaries by computer is evident here, or alternatively, a centralized statistician/programmer working for several government departments in smaller island states.
