2 Recreational fishing data
2.1 Data sources
The rec_data database is designed for data from a range of recreational fishing surveys. In 1991, the Ministry of Fisheries (then MAF Fisheries) initiated marine recreational fishing catch and effort diary surveys and boat ramp surveys.
The first diary survey, in 1991-92, was of fishers living in the South region, (Bell et al 1993,) the second, in 1992-93, was of fishers living in the Central region (Ryan et al), and the third, in 1993-94, was of fishers living in the North region (Bradford 1996). A national survey was run in 1996 (Bradford 1998, Bradford et al 1998) and another in 2000. Local diary surveys have been conducted in areas including Patterson Inlet at Stewart Island, Akaroa, Bluff and Otago harbours, Fiordland, Kaikoura, Wellington and Marlborough.
The first boat ramp survey in 1990-91 was of fishers started in the North region (Sylvester 1993), followed by the Central region in 1992-93 (Ryan et al), the North region in 1994, and nationally in 1996 (Hartill et al 1998) and 2000.
A boat ramp survey was also conducted at a small number of locations in 1998 in the North region. Other regional boat ramp surveys have also been conducted in areas including Kaikoura, Marlborough and Maketu. Boat ramp surveys have been run regularly in the north region since 2000.
Data from shellfish harvest surveys at sites from December 1997 in the North region are also held in this database. (For a more detailed list of the surveys, refer to Appendix 3.)
Data are derived from 2 main sources: boat ramp and diary surveys.
For the boat ramp surveys the top level unit of sampling is a session, where an interviewer meets the fishers at the completion of their fishing trip at the boat ramp or beach. For each group or boatload of fishers intercepted, information including the time of the intercept is recorded. Assuming the group have been fishing as opposed to other activities, and that they agree to be interviewed, then details of the fishing effort of the individual fishers, including method used and location fished are recorded. Details of the length of species landed are recorded along with counts of the number of fish.
Shellfish harvest surveys are conceptually regarded as analogous to the boat ramp surveys.
Observer surveys are regarded as similar to the boat ramp surveys, however fishers are not interviewed but indicators of fishing effort are counted, e.g., boats, buoys, kayaks or people fishing.
The diary surveys were mostly preceded by a telephone or intercept survey, that collected details of the diarists fishing practices in the last year and personal details including age and sex. The basic unit of fishing effort is a trip by a diarist or respondent. The trip data (which includes: the date of the trip, where fished, by what method, and for how long) was supplied by the diarists on a trip record form by return envelope through the post. These data include details of the catch including species and numbers caught. Note that one trip by a diarist on one day may be recorded as 2 or more trips on the database; if, for example, the diarist used 2 or more fishing methods that day. A subset of diarists in the national 1996 survey also filled out details of the length of snapper, kahawai, and blue cod from their catch. Some diarists from the Kaikoura survey also recorded the length of fish from their catch.
2.2 Data validation
While the rec_data database enforces data validation and integrity rules with the use of referential constraints and range checks, the data go through a rigorous data validation and error checking process before being entered.
This process includes simple data validation using perl language scripts, followed by inserting data into a loading database where further checks are carried out using SQL (Structured Query Language). See Appendix 1 for a more detailed description of the processes involved.