Projects

View All Projects

Billfish Logbooks

The New Zealand billfish logbook programme is designed to collect catch and effort information from recreational vessels targeting marlin off northern New Zealand during the season, December through May.

Funded by the Ministry for Primary Industries
Researchers Blue Water Marine Research

Billfish logbooks

The New Zealand billfish logbook programme is designed to collect catch and effort information from recreational vessels targeting marlin off northern New Zealand. Information on the catch of mako sharks and yellowfin tuna is requested as these are also important fisheries.

The programme has been developed following consultation with key participants in the fishery. The logbook is designed for charter boat operators and skippers of private vessels who fish frequently. The data collected will complement and assist in the understanding of catch records collected by fishing clubs affiliated to the New Zealand Big Game Fishing Council.

The fishing diary we supply will be a great personal record for your own use. The focus of the survey is striped marlin and we already have a 30 year time series of striped marlin catch and effort from the annual postal survey of billfish charter boat skippers, which was started by Pete Saul in 1977.

Figure 1. The line is the catch rate by charter boats fishing off east Northland since 1977. The dots are the difference from the average (anomaly) of January sea surface temperatures for that year.

marlin-catch-rate

 The line in the graph above shows the average number of striped marlin caught per day by charter boats off east Northland (not the 3 Kings) since 1977. Higher catch rates are often associated with warmer years (as indicated

 by the red dots near the top of the plot), which are the sea surface temperature anomaly for January each season.

Information on catch and effort is vital to monitor any fish stock. The commercial records since 1988 are patchy as they are not able to land marlin taken on commercial vessels in New Zealand waters. The only consistent data we have for this fishery comes from recreational records.

By collecting catch per unit effort information and factoring in changes in fishing area, methods, gear, sea surface temperature and weather conditions we can investigate trends in the striped marlin fishery back to the 1970s.

The New Zealand fishery tends to catch large striped marlin and is on the southern boundary of their distribution. The quality of our striped marlin fishery may be a good indicator for the status of the stock across the south west Pacific region.

Join the Billfish Logbook Programme and receive:

  • A free bound logbook with year planners, conversion tables and other useful information. We only need a copy of the log book forms;
  • An exclusive email newsletter with the latest information on billfish and tuna research projects in New Zealand;
  • Free supply of the new nylon tipped billfish tags;
  • Free Billfish Logbook polo shirt when your logbook is returned;
  • Feedback on the project progress and results. Feedback is vital for the long term success of the project and recognition of its value.

Email John@bluewatermarine.co.nz or Phone 09 434 3383 to join.

Site by Big Fish Creative