Abstract:
Recreational fishers in New Zealand often make use of lunar and indigenous Maori fishing calendars in order to predict fishing success on specific days. Little is known as to the performance of such predictions and whether or not they hold any practical use to the everyday angler. Here, generalised nonlinear mixed effects models are built in AD Model Builder (ADMB) and WinBUGS using recreational fishing data provided by the Ministry of Fisheries. These data are based on catches of snapper Pagrus auratus, New Zealand's most popular recreational species, and take the form of diary and boatramp surveys. Evidence is found for a relationship between lunar phase and fishing success, and also to support some aspects of the performance of the Maori fishing calendar predictions. The magnitudes of these effects are small, however, casting doubt on the practicality of lunar based fishing predictions. These analyses also allow for the assessment of ADMB in its capabilities of explaining large datasets using complex nonlinear mixed effects models.