Mahi-Mahi Fishing Guide: How to Catch Dolphin Offshore

If you've never tangled with a mahi on light tackle, you're missing one of the best fights in saltwater. These fish hit like freight trains, jump like acrobats, and light up in neon greens and yellows that make every other gamefish look dull. Off the Carolina coast, mahi season means fast action, cooler full of fillets, and the kind of day on the water that keeps you coming back.

Mahi-mahi (also called dolphin or dorado) are the perfect offshore gamefish. I've had days off Hatteras where we boated 30 fish before lunch, and days where we trolled for six hours without a knock. They're aggressive, abundant, and arguably the best-tasting fish in the ocean. Whether you're trolling the Gulf Stream out of Morehead City or casting to weed lines off Hatteras, here's everything you need to put mahi in the box.

Understanding Mahi-Mahi

Mahi-mahi (Coryphaena hippurus) are pelagic predators found in warm waters worldwide. They're one of the fastest-growing fish in the ocean, reaching 30+ pounds in their first year. Bulls (males) develop that distinctive blunt forehead, while cows (females) have a more rounded head profile. Most mahi you'll catch off the Carolinas run 5-20 pounds, with bulls over 40 pounds being legitimate trophies.

These fish are built for speed and aggression. They feed on flying fish, ballyhoo, squid, and anything small enough to fit in their mouths. Mahi are schooling fish, especially the smaller "schoolies" in the 2-10 pound range. Find one and you've usually found a bunch. Bigger bulls tend to travel in pairs or small groups.

Mahi prefer water temperatures between 72-82 degrees F and are almost always associated with some kind of floating structure. Weed lines, debris, lobster pot buoys, floating pallets, and even a single 2x4 can hold fish. If it floats, mahi will find it.

Finding Mahi Offshore

The number one rule for mahi fishing: find the stuff. Floating debris, weed lines, and current edges hold bait, and bait holds mahi. Off the NC coast, the Gulf Stream pushes warm, clean water within 20-40 miles of shore depending on the season. That's where the action lives.

Key structure to target:

• Weed lines and sargassum mats. The single best indicator of mahi. Troll along the edges and cast into gaps where floating grass concentrates.
• Lobster and crab pot buoys. Nearshore pot markers hold surprising numbers of mahi. A quiet approach works best since fish spook from engine noise. Live chumming with menhaden around pots is deadly.
• Floating debris. Pallets, logs, buckets, doors (charter captains have literally found tripletail and mahi holding on someone's front door miles offshore). Anything floating is worth a look.
• Temperature breaks and color changes. Where clean blue Gulf Stream water meets green coastal water, bait congregates along the edge. Troll the line.
• Bird activity. Frigate birds and terns working over bait often mark mahi underneath.

Binoculars are essential for spotting distant weed patches, birds, and debris. I've found that a good pair of 7x50 marine binoculars pays for itself on the first trip.

Pay attention to water temperature. Mahi rarely hold in water below 70 degrees. Use your electronics to track temp breaks while running offshore. When you find 74-78 degree water with color and floating grass, you're in the zone. The best days happen when clean Gulf Stream water pushes within 25 miles of the beach, which can happen any time from May through September off Morehead City and Wrightsville Beach.

Trolling for Mahi

Trolling covers water fast and finds scattered fish. The standard mahi trolling spread runs at 6-9 knots (see our trolling speed chart for species breakdowns) and includes a mix of skirted ballyhoo, small lures, and naked baits.

The go-to rig for about 95% of mahi trolling is a "dink rig": a 6-foot section of 60-pound mono tied to a 6/0 or 7/0 Gamakatsu O'Shaughnessy hook, rigged with ballyhoo and a 1/4-ounce egg sinker as a chin weight. Run 4-6 of these at staggered distances behind the boat.

Sea Witch lures and trolling skirts dressed over ballyhoo add color and vibration. Blue-and-white, pink-and-white, and chartreuse are proven colors. Small trolling lures like feathers and small jets produce well for schoolies.

When you hook a fish, keep it in the water next to the boat. Mahi are schooling fish, and a hooked fish attracts others. This is when you switch to casting and maximize the school. For more on setting up a trolling pattern, see our trolling spread guide. Our king mackerel guide also covers trolling techniques that overlap with mahi fishing.

Casting and Light Tackle

Once you find fish or stop on structure, casting is where the real fun starts. Spinning gear with 20-30 pound braid and a 30-40 pound fluorocarbon leader is perfect. A 7-foot medium spinning rod with a 3000-4000 reel gives you the distance and fight quality that makes mahi fishing addictive.

Small soft plastics, metals, poppers, and bucktails all catch mahi when they're fired up. Prismatic swimming plugs cast around floating structure draw reaction strikes. For deeper fish holding 20-40 feet down, heavier metals and diamond jigs get down fast.

Live bait is the ultimate mahi magnet. We've had our best days when we took the time to catch live bait before running offshore. Live peanut bunker, killies, or sardines create a feeding frenzy. Chunk sardines into one-inch pieces for chum, then pitch live baits on 1/0-3/0 live bait hooks into the chaos. Heavier gear with larger baits like butterfish or whiting targets the bigger bulls hanging below the school.

Tackle Setup for Mahi

Mahi don't require exotic gear. Here's what works:

• Trolling rods: 5.5-6.5 foot medium-heavy, matched with conventional reels in the 20-30 pound class. Load with 30-50 pound braid or 20-30 pound mono.
• Casting/spinning: 7-foot medium power with 3000-4000 size reel and 20-30 pound braid.
• Leaders: 30-60 pound fluorocarbon depending on fish size and water clarity. Mahi aren't leader shy but clear water calls for lighter.
• Hooks: 6/0-7/0 for trolling rigs, 1/0-3/0 for casting and live bait.
• Gaff: A 3-foot gaff for anything over 10 pounds. Mahi thrash violently at the boat, so gaff shots need to be quick and decisive.

Good pliers are essential. Mahi swallow hooks deep, especially on bait. Long-nose pliers save time and prevent cuts from teeth and gill plates. Check our live bait vs. artificial guide for more on when to troll versus cast. For rigging details, our live bait rigging guide covers hook placement and leader setup.

Seasons and Best Times

Off the Carolinas, mahi season generally runs May through October, with peak action from June through September when Gulf Stream water pushes closest to shore.

• May-June: First wave of fish arrives. Smaller schoolies dominate early, with bigger bulls following. Water temps hitting 72+ trigger consistent action.
• July-August: Peak season. Weed lines build, debris accumulates, and fish are everywhere in the Stream. This is when 50+ fish days happen if you find the right weed mat.
• September-October: Second migration brings another wave of fish. Fall mahi can be larger as they feed heavily before moving south. This is often the best window for trophy bulls.

Mahi fishing rewards the angler who covers water and stays flexible. Some days you'll troll for hours before finding a weed line that produces. Other days you'll see green-and-gold shapes busting the surface before you even get lines in. Full moon periods can push fish deeper during the day, so consider deeper-running lures and heavier egg sinkers on your rigs during bright moon phases.

The Gulf Stream current runs roughly 2-4 knots, which means trolling with the current covers ground faster but puts less action on your lures. Troll against or across the current for better lure action, then reposition and make another pass. Working a productive weed line from multiple angles maximizes your time in the strike zone.

Tips for More Mahi

• Keep one in the water. A hooked mahi attracts the school. Leave a fish swimming alongside the boat while others cast to the school.
• Bring live bait. When you can get live bait, bring it. Mahi are more selective toward artificials without live bait in the water to fire them up.
• Approach structure quietly. Cut your engines and drift into weed lines and pot buoys. Engine noise scatters fish.
• Use brightly colored lures. Chartreuse, pink, blue-and-white, and anything flashy matches mahi's aggressive visual hunting style.
• Bleed them immediately. Mahi have incredible table quality, but only if you bleed and ice them right away. A quick gill cut and straight into the fish box.

Mahi-mahi fishing is pure fun. Fast action, beautiful fish, incredible table fare, and the kind of offshore excitement that makes long boat rides worth every minute. Whether you're dragging ballyhoo through the Stream or pitching live bait to fish stacked under a weed mat, every trip has the potential for a cooler full of fillets and a few stories worth telling.

Get your trolling spread dialed in, watch for the birds and the grass, and be ready to switch to casting the second you find fish. The best mahi days happen when you stay flexible and cover water until you find what's holding fish that day. Once you find the bite, milk it for everything it's worth. Tight lines.

Questions about mahi tackle? Call us at 888.453.3742 or email help@thetackleroom.com.

Know Before You Go: Regulations change frequently. Always check current size limits, bag limits, seasons, and gear restrictions with your state fisheries agency before heading out. For Atlantic species, visit ASMFC.org for interstate management updates.