Waterman's Journal

Apr 14, 2022


Black Marlin Fishing in Costa Rica – the secret is out!

When it comes to targeting Black Marlin, most people think they need to travel all the way to Australia’s Great Barrier Reef to catch a glimpse of one of these apex predators… but let me tell you a little secret… Costa Rica has a GREAT black marlin fishery!!! and its relatively untouched because most crews tend to target blue marlin and sailfish which are also very plentiful in Costa Rica.  Join Captain Ron and the crew of PELAGIC as they share some of their secrets and provide valuable insights, strategies, and tactics for targeting black marlin in Costa Rica…

Above: The majestic Black Marlin is on every serious angler's bucket list. || photo by Adrian Gray

How to tell the difference between a Black Marlin and a Blue Marlin?

Black and Blue Marlin are definitely two of the most sought after pelagic gamefish in the world. Both species are super aggressive apex predators that can grow to well over 1,000 pounds or more. To the casual observer, black and blue marlin look very similar, but there are several key differences that set apart the two species.

The black marlin (Istiompax indica) is a species of marlin found in tropical and subtropical areas of the Indian and Pacific Oceans. They are considered by many to be amongst the world's premier gamefish. They certainly have size on their side, with the all-tackle world record black marlin weighing in at 1,560 lbs. taken by Alfred Glassell way back in 1953 off Cabo Blanco, Peru. Over the years, there have been reports of several commercial landings that have seen black marlin tip the scales at over 2,000 pounds – however, these fish were caught in nets and on commercial long lines, rather than on traditional rod and reel.

Above: Alfred Glassell stands next to his world record 1,560 pound black marlin caught in 1953 off Cabo Blanco, Peru.

Above: Captain Cornelius Choy with his massive 1,805 pound blue marlin caught in 1970 off Honolulu, Hawaii.

The blue marlin, (Makaira Nigricans) can be equally massive in size, if not bigger, with a 1,656 lbs. blue marlin caught by the legendary “Black Bart” Miller in 1984 and of course “Choy Lees Monster” blue marlin caught in 1970 that weighed in at 1,805 lbs. – both of these fish were caught on rod and reel off the Hawaiian Islands.

But how are these fish different? And what are the best ways to tell them apart? First of all, black marlin can be found ONLY in the Pacific and Indian Oceans, and NEVER found in the Atlantic. So if you catch a large marlin in the Atlantic ocean, its probably NOT a black. Generally speaking, black marlin can often be found hunting their prey in shallow nearshore waters (from 200 to 2000 feet deep), while blue marlin are found primarily offshore, in deep open waters far from land.

Above: The crew of PELAGIC prepare to release a Costa Rican black marlin.

As for physical differences, the black marlin has a larger head, a shorter more thick and stubby bill, and a rounder and lower dorsal fin. One of the best ways to positively identify a Black marlin from all other marlin species is by their rigid pectoral fins that are unable to be folded flat against their sides like all other marlin species. Also, their dorsal fin is proportionately the lowest of any billfish, it stands less than 50 percent of the fish's body height. Black marlin are renowned for their sporting hardiness, powerful water antics and ability to test the most experienced anglers. A highly rated game fish, the black marlin has the power, size, and persistence of which anglers dream.

Costa Rica Map

Where to find Black Marlin

As you may recall, BLUE marlin are typically found far offshore, in deep waters around banks, upwellings, and temperature breaks. Turns out, BLACK marlin are pretty much the opposite - they are usually found hunting in relatively shallow waters, near shore, around structure that hold bait. Typically, they are found in depth ranges from 200 to 2000 ft, although they rarely swim deeper than 100 feet below the surface. This behavior makes fishing around nearshore banks and pinnacles an excellent tactic for targeting these highly prized billfish.

Above: Located on the Pacific Coast of Central Costa Rica, Marin Pez Vela is a super clean, world-class marina and the home port of the world famous PELAGIC charterboat.

Finding Black Marlin on the water in Costa Rica

Fishing along the Central Pacific Coast of Costa Rica, you will find plenty of rocky outcroppings along the beach, which is a good indication that there is similar bottom structure located just a few miles offshore, in about 1000 to 2000 feet of water. Look for open water pinacols, drop-offs, reef edges and structure that hold mid-sized bait such as skipjack tuna and bonito. Once you find the structure that is holding bait you are in the zone, keep your eyes on your sonar as you may even catch a black marlin prowling beneath the boat.

Above: The depth sounder showing a rocky structure that rises from the depth of 1,500 feet to just 238 feet - this is a prime spot to target black marlin by slow-trolling live skipjack tunas.

What do black marlin eat?

The Black Marlins diet mostly consists of various small to mid size schooling baitfish, like small tunas, flying fish, jacks, mackerels, mahi, and squids. Giant black marlin have even been spotted taking down large tunas and small billfish, they are fierce apex predators.

Above: The crew of PELAGIC bridles a live skipjack tuna intended to entice a Costa Rican black marlin.

How big do black marlin grow?

Black Marlin grow very fast. The female of the species grows faster and larger than the male. For example, juvenile fish can reach around 33 lbs in their first year and up to 110 lbs by the time they are three years old. If adequate food is available its possible for a female to reach over 1000 lbs by the time she is 10-12 years old. In contrast, males rarely reach more than 500 lbs in weight.

When is the best time of year to catch Black Marlin in Costa Rica?

Black marlin are most abundant in Costa Rica in May, June, July, and August, but like its cousin the blue marlin, we have been seeing more and more throughout the year. Black marlin fishing is the best around the areas of Central and Southern Costa Rica.

How do you target black marlin in Costa Rica using live bait?

Step one is to catch live bait, our most successful method is to troll a combination of small shiny spoons and skirted hoochies behind a planer rig that takes the baits to 10’ to 20’ down where mid-sized bonito and skipjack school up. To keep the small tunas alive, most high-end charter boats are outfitted with tuna tubes that help keep your baits fresh and lively until ready to be deployed.  Aboard PELAGIC, we have a total of ten tuna tubes that we like to be filled completely, before we start fishing.

Above: Captain Ron deploying a "silver bullet" - a 12-inch skipjack tuna - which is an ideal bait for hungry black marlin prowling the waters of Costa Rica.

Once we have filled our tubes with bait, we are ready to rig and deploy our first baits of the day. We normally start fishing in the same spot that we caught bait, because predators are usually found near bait. Our preferred method of fishing for Black Marlin is slow trolling live tunas like skipjack, bonita, and small yellowfin. Bridle rigging is best for this type of slow trolling, as this technique keeps the circle hook completely exposed and in front of the bait so it can swim freely and naturally.

It's important to have the correct rigging tools such as an "open eye" rigging needle and a 6” loop of rigging floss or a heavy-duty rubber band. To start your bridle rig pass the needle through the fish's eye sockets on the forward area of the head. Next, slip the hook point into the floss loop where the needle was and twist it 3-4 times until the two doubled floss lines are wrapped tight. Finish the rig by passing the hook point from front to back between the fish's head and the floss. This position allows the fish to swim naturally as it is pulled along by the boat.

Above: The nearshore waters off Quepos, Costa Rica feature plenty of rocky pinnacles and structure that make it an ideal location to target black marlin.

When black marlin are in feeding mode, they are voracious predators that will attack almost anything big enough to get their attention that is presented in a natural manner.  Aboard PELAGIC, our number one preferred fishing method for black marlin is slow trolling a 12 to 14 inch bridled skipjack tuna. Remember, bigger baits require more time for the fish to swallow so don’t be too eager to set the hook… let-her-eat!!!!

Pro-tip: When there are black marlin in the area but your not getting bit, try dropping down in leader size, so its harder for the fish to detect the line.  For example if you switch from 200 lb test leader to 130 lb it may help increase your chances of getting the bite due to the decreased diameter of the lighter line, which gives a more natural bait presentation. That is all but guaranteed to persuade even the wariest billfish to bite.

Above: PELAGIC, a 58-foot Garlington Custom Sportfisher, is an excellent fishing platform with a world-class crew to put you on the fish day in and day out.

How to Hire the right boat and guide?

Live baiting marlin is a specialized technique that can be extremely effective for black marlin. Costa Rica has a number of great captains that specialize in marlin fishing but ask specific questions to find a boat that has had recent success specific to black marlin. This may require some over the phone or on the dock recon.

What kind of fishing tackle and gear is needed to catch black marlin in Costa Rica?

Remember: Black marlin are much more aggressive and powerful predators than many other fish. If you are trying to catch a bucket list fish don’t go in under-gunned, a large black marlin will take everything you’ve got to land. Here’s what is recommended as standard tackle for catching Costa Rican black marlin:

● 6-7 foot conventional boat rod with extra heavy action with good backbone
● Strong conventional reel like a Shimano Talica 50 or Tiagra 50 two speed reel
● 100 to 130 pound braid or spectra backing
● 80 to 130 pound monofilament mainline
● 130 to 300 pound fluorocarbon leader
● 10/0 to 12/0 Owner circle hooks

Above: PELAGIC heads in after catching a Grand Slam of sailfish, blue marlin, and black marlin.

Conclusion on live baiting black marlin in Costa Rica.

When it all comes together, catching a black marlin on live bait is an overall incredible experience. From finding the perfect spot, to dropping back a perfectly rigged bait, to watching your bucket list fish explode on the surface and then landing a trophy black marlin; there are few experiences in sportfishing that even come close. Remember you can tip the odds in your favor by hiring the right boat, captain, and crew that knows how to target these iconic marlins. Hopefully, this article will help you to get one step closer to catching that elusive bucket list fish – the Black Marlin - and tame one of the largest predators in the ocean.

Ronald “Captain Ron” Kawaja: Captain Ron is the president and founder of Pelagic clothing company and a world-class angler who has traveled the globe for the past 20+ years in search of big fish, exotic fishing destinations, and pure ocean adventure. His voyages have included fishing & competing in the world’s largest and richest sport fishing tournaments; pursuing the elusive “grander” (1,000+ pound marlin or tuna) on rod and reel; and seeking out the world’s ultimate fishing destinations in places like Australia, Africa, Ascension Island, Bahamas, Belize, Brazil, Cabo, Cancun, Costa Rica, Dominican Republic, Guatemala, Madeira, Nicaragua, Panama, and Puerto Rico (to name a few). Over the years, Captain Ron has won and placed in numerous fishing tournaments around the world, including the prestigious White Marlin Open in Ocean City, MD where he was named “Grand Champion & Top Overall Angler” - to win this title, Kawaja competed against more than 2,000 anglers, and finished in first place. As recently as October 2021, Captain Ron led his team to a first place victory against 189 of the world’s top sport fishing teams at the world famous Bisbee’s Los Cabos Offshore Tournament in Cabo San Lucas, Mexico.  As an angler, he has extensive experience in a diverse range of fishing situations, from fighting giant fish up to 1,000 pounds on stand-up tackle, to chasing light line world records, and he credits 100% of his success to all the pro captains and crews he has fished with and learned from over the years.