Offshore Fishing Charter, Marathon FL – Mahi Mahi and Tuna
If you're looking for some serious offshore action in the Florida Keys, Captain Alex's Marathon charter is where you want to be. This isn't your typical half-day trip close to shore – we're talking about a full 6-hour adventure targeting two of the most sought-after game fish in these waters: Mahi Mahi and Blackfin Tuna. Whether you've been fishing these waters for years or you're just getting your feet wet with offshore angling, Captain Alex knows how to put you on fish. The boat handles up to 4 anglers, so you'll have plenty of room to work without feeling cramped when the action heats up. Keep in mind that fuel runs about 40-50 gallons for the day and isn't included in your charter rate – that's just part of getting out to where the big fish live. All your tackle and gear are provided, and you'll settle up the remaining balance right there at the dock before we head out.
What to Expect on the Water
Marathon sits right in the heart of some of Florida's most productive offshore waters, and Captain Alex knows every current break, weed line, and structure that holds fish. We'll be running anywhere from 8 to 20 miles offshore depending on where the fish are showing up and what the conditions look like. The Gulf Stream influence here creates the perfect setup for pelagic species, with temperature breaks and current edges that concentrate baitfish – and where there's bait, there's game fish. You'll spend your day working blue water that can range from 200 to over 1000 feet deep, watching for bird activity, floating debris, and those telltale signs that fish are feeding. The vibe is relaxed but focused – Captain Alex will keep you moving and fishing efficiently while making sure everyone on board gets their shots at fish. Even if you've never caught anything bigger than a snapper, don't worry. The captain will walk you through everything from how to work the drag to proper fighting technique when you hook up.
Trolling Tactics & Gear
Most of your day will be spent trolling, which is hands-down the most effective way to cover water and find active fish in the offshore environment. Captain Alex runs a spread of lures and baits designed specifically for Mahi and Tuna – think ballyhoo rigged behind colorful skirted trolling lures, feathers, and maybe some cedar plugs or diving plugs depending on conditions. The boat is rigged with outriggers to spread your baits wide and keep them in the clean water behind the boat's wake. When we mark fish on the finder or spot diving birds, we might switch to live bait fishing or chunking to get them fired up. The tackle is sized appropriately for the target species – heavy enough to handle a big bull Mahi or a screaming Blackfin, but not so heavy that it takes the fight out of the fish. You'll be fishing conventional reels spooled with 30-50 pound test, paired with rods that have the backbone to move fish but enough flex to keep from pulling hooks. If you've got your own gear and prefer to use it, just let Captain Alex know ahead of time so he can make sure it's appropriate for what we're targeting.
Target Species
Mahi Mahi, also called Common Dolphinfish, are absolutely what dreams are made of when it comes to offshore fishing. These fish are built for speed and acrobatics – when you hook a Mahi, especially a bull over 20 pounds, get ready for jumps, runs, and head-shaking that'll test your drag and your nerves. They're attracted to floating structure like sargassum weed, debris, and even floating trash, which makes them relatively predictable to target if you know what to look for. The best part about Mahi fishing in Marathon is that they travel in schools, so when you find one, there's usually more around. Peak season runs from late spring through early fall, but you can find them here almost year-round when conditions are right. Bulls can push 30-40 pounds, while the smaller "schoolies" typically run 5-15 pounds – but don't let the size fool you, even a small Mahi will give you a fight you won't forget. Plus, they're absolutely gorgeous fish with those brilliant gold and green colors, and they make fantastic table fare if you decide to keep a few for dinner.
Blackfin Tuna are the other stars of this show, and they're every bit as exciting as Mahi but in a completely different way. These fish are pure muscle – compact, torpedo-shaped speedsters that'll burn drag like there's no tomorrow. Blackfins in these waters typically run 10-25 pounds, which might not sound huge, but pound-for-pound they're some of the strongest fish you'll ever tangle with. They travel in schools and feed aggressively, often pushing bait to the surface where you can see the commotion from a distance. When they're feeding up top, it's game on – you can cast into the school with live bait or lures and hook up immediately. The key with Blackfins is staying tight to them once you're hooked up because they'll sound deep and try to cut you off on anything they can find. They're most active during cooler parts of the day and can be found year-round in Marathon's offshore waters, though they seem to concentrate more during the winter months when water temperatures drop slightly. If you're looking for sushi-grade fish, Blackfin Tuna is about as good as it gets – the meat is dark red and incredibly flavorful.
Time to Book Your Spot
Captain Alex's offshore charters book up fast, especially during peak season when the fishing is hot and weather windows are consistent. This 6-hour format gives you the time you need to really get out there and work the water properly – no rushing, no feeling like you just got started when it's time to head back. With only 4 spots available