Marlin: Blue

Pacific blue marlin, Atlantic blue marlin, Indo-Pacific blue marlin, black spearfish, A’u

Makajiki, Mekajiki

Blue marlin are caught (primarily incidentally) throughout the Pacific Ocean in domestic and international troll, longline, and purse seine fisheries. They have a short life span and reach sexual maturity at an early age making them less vulnerable to fishing pressure. The data for Pacific blue marlin are highly uncertain, but suggest that the stock is fully exploited with a long-term biomass decline and a more recent increasing trend.

Marlin are caught with troll, handline, and pole and line gear, pelagic longlines, and purse seine gear. The level of bycatch varies according to the gear type. Purse seine sets on floating objects or fish aggregating devices (FADs) are deemed a high conservation concern due to the bycatch of juvenile tuna, other pelagic fishes, sharks, and sea turtles. The uncontrolled growth of the floating object fishery is cause for concern. Pelagic longlines also catch a number of incidental species, including endangered and threatened sea turtles, seabirds, and marine mammals.

In the international waters of the Pacific Ocean, management of blue marlin falls under the purview of the Western and Central Pacific Fisheries Commission (WCPFC) and the Inter-American Tropical Tuna Commission (IATTC), and the Western Pacific Fishery Management Council in U.S. waters. As marlin are caught incidentally in the pelagic longline fisheries targeting tunas and swordfish, management of these fisheries is used to evaluate the management of blue marlin. There is no management for blue marlin, with the exception of the Hawaii based longline fleet, where bycatch mitigation efforts have been implemented, and the fishery is closed when sea turtle bycatch caps are reached.

Blue marlin has a high intrinsic rate of increase, reaches maturity at a relatively young age, and is moderately long-lived with a maximum age of greater than 20 years. Overall, blue marlin exhibits life history characteristics that should make it inherently resilient to fishing pressure.

Blue marlin is considered fully exploited. Fishing mortality is thought to be below acceptable sustainability thresholds, but stock uncertainty is high.

Blue marlin biomass has exhibited a long-term decline, with a more stable trend in recent years. Overall, the stock status of a blue marlin in the Pacific is considered a “moderate” conservation concern.

Bycatch by pelagic longline and FAD/purse seine sets is remains a critical conservation concern due to the continued bycatch of sea turtles, seabirds, marine mammals, sharks, billfishes and other pelagic fishes.

Pelagic longline, FAD/Purse seine gear have moderate habitat effects, but the ecosystem effects of removing large predators such as blue marlin remains controversial.

There is essentially no international management of blue marlin, which is a critical conservation concern.

Where was this Marlin caught?

How was this Marlin caught?

Only Blue Marlin from the Hawaiian fleet is ranked as “some concerns”. Blue marlin from areas other than Hawaii, and all Striped marlin should be avoided.

Elevated mercury levels + Women should not eat at all + Kids up to age 12 should not eat at all + Men should eat no more than 1 meal per month

No.