Analysis of Big Game Fishing Catches of Blue Marlin (Makaira nigricans) in the Madeira Archipelago (Eastern Atlantic) and Factors that Affect Its Presence

Roi Martinez-Escauriaza,Margarida Hermida,Nuno Manuel Abreu Gouveia,Maria Lídia Ferreira De Gouveia,Mafalda De Freitas,Eduardo Teixeira,Pablo Pita

doi:10.3390/su13168975

Abstract

The archipelago of Madeira (Portugal) is one of the main European big game fishing locations, where the main target species is the blue marlin (Makaira nigricans). Catch data for these fish were used to analyze their presence over the years, estimate their average weights, and calculate annual fishing success rates. The results showed a marked seasonal effect, with higher average catch rates in summer (June–July), suggesting a migration from the equatorial waters they inhabit at the beginning of the year to northern areas when the waters become warmer. The influences of some environmental factors were analyzed using generalized additive models, and it was observed that the occurrence of blue marlin may be influenced by water temperature, wind, rain, and atmospheric pressure. This fishery did not register a high mortality rate in blue marlin specimens due to the usual practice of catch and release; individuals captured in this fishery can be used as a source of information that allows for follow-up on the status of the blue marlin population in the region.

Highlights

Blue marlin (Makaira nigricans, Lacepède, 1802) is an epipelagic oceanic species distributed throughout tropical regions, which spends most of its time near the surface at night and at greater depths (25–100 m) during the day [1]
These data indicate the effort made by each boat, and allowed the calculation of their catch per unit effort (CPUE) (Table 2)
In 2019, a total of 280 blue marlins were caught, corresponding to a CPUE of 0.049 and a total of 5760 h trolled over 857 fishing trips

Summary

Introduction

Blue marlin (Makaira nigricans, Lacepède, 1802) is an epipelagic oceanic species distributed throughout tropical regions, which spends most of its time near the surface at night and at greater depths (25–100 m) during the day [1]. In the Atlantic Ocean, adults are commonly found in waters with SST ranging between 22 and 31 ◦ C [6,7]. This species has a low market value, catches are not negligible, especially due to the frequent accidental catches by pelagic longliners targeting tuna (Thunnus spp.) and Sustainability 2021, 13, 8975.

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Conclusion