Ask most people what tuna fishing in Southern California means and they'll say bluefin. Fair enough — the cows get the photos, the podcasts, and the sleepless nights. But bluefin also ask for a longer trip, heavier tackle, and a tolerance for being refused by fish that can spot your leader from twenty feet away.
Yellowfin are the other answer. They're more forgiving, they're inside the range of boats that don't require you to clear three days off your calendar, and right now they're around. When the fleet posts 200 yellowfin off a single trip, that's not a fluke. That's what a warm-water August looks like.
The catch is that catching them well means understanding a piece of ocean most people never think about: a mat of floating kelp the size of a card table, drifting in a thousand feet of water, holding an entire food chain underneath it. Find those, work them correctly, and the rest follows.
First: the El Niño in the room
You've probably heard it mentioned at the landing this summer. It's worth understanding, because it shapes what's realistic between now and the end of the year.
NOAA's Climate Prediction Center has an El Niño Advisory in effect. In its August 13 diagnostic discussion, the agency reported that El Niño strengthened again through July, with sea surface temperature anomalies exceeding +2.0°C in the eastern equatorial Pacific, and put the odds of a very strong event during fall and winter at greater than 90 percent.
For an angler the translation is simple: warm water moves north, and the fish that live in warm water come with it. Yellowfin follow water in roughly the 72–82°F range, and so do dorado. In a normal year that band sits well south of us for most of the season. In a strong El Niño year it pushes up the coast, drags the bait with it, and brings the whole warm-water cast into range earlier and in better numbers.
It's worth being honest about the other side of that. Warm water isn't universally good news — strong El Niño conditions can suppress the cold-water upwelling that drives much of our local productivity, and species that want colder water get scattered or pushed out. A banner tuna season and a strange local season aren't contradictory. They're the same thing viewed from two angles.
But if yellowfin are what you're after, the setup between now and October is about as good as it gets here.
Why yellowfin fish differently than bluefin
A bluefin mindset will make you overwork this.
They're less leader-shy. Bluefin refuse baits over line they can see, which is why that game lives on light fluorocarbon. Yellowfin are more forgiving — though as you'll see below, "more forgiving" doesn't mean "fish heavy and don't think about it."
They follow a hooked fish. This is the single most exploitable thing about them, and it's the foundation of the entire program described below.
They hold on structure. Floating kelp is the classic. Yellowfin also travel under pods of dolphin, and boats work those the same way.
They're reachable. Yellowfin generally show off San Diego from around July into October. Bluefin usually want a longer run.
Finding the paddy
The run out isn't just transit. It's searching.
The productive approach is to get out past the offshore banks and look for a temperature break — the seam where warm and cool water meet. That's where the junk collects. Kelp, debris, anything floating gets pushed up against that line, and with it comes the bait and everything eating the bait.
Boats scan at around 6 to 8 knots, not at full speed. Someone should be up high with good binoculars watching for working birds, boils on the surface, or a piece of kelp sitting out there by itself. Birds sitting on a paddy are one of the strongest tells there is.
The moment you spot one, mark it on the plotter. Wind and current move paddies, and a paddy you can't relocate is a paddy you didn't find.
Not every one holds fish. Most hold very little. On a good day the boat may check a dozen to find three worth working.
Working the paddy
This is where most of the mistakes happen, and it's the part a research article usually gets wrong.
Don't drive up on top of it. Ease in from upwind or up-current and let the drift carry you past, staying 15 to 20 yards off, with the engine down if conditions allow. A boat that motors straight onto a paddy pushes the school down and off.
Start chumming before you arrive. Sardines or anchovies — whatever the bait receiver had that morning — going over the rail as you come to a stop, not after. The chum line should be working by the time the boat settles.
The fish usually aren't glued to the kelp. They'll be anywhere from a few feet underneath it to well off to the side. Don't be afraid to work a chum line out away from the paddy entirely. Some of the best fishing happens forty yards from the thing everyone's staring at.
On an open-party boat this is the crew's job, not yours — but knowing what they're doing tells you where to put your bait, and why the captain stopped somewhere that looks like nowhere.
What to have rigged
The single biggest difference between a good day and a frustrating one is being ready before the boat stops. When the stop happens, it happens fast.
Main outfit: a 7'6" to 8' rod rated 20–30 lb with a small lever-drag reel — Avet SX or Trinidad class. This is the setup for pitching a bait light and easy, and it'll handle most of what you'll hook.
Second outfit: something a bit heavier, 20–40 lb, for when the grade steps up or you need to turn a fish away from the kelp before it wraps you.
A jig rod, rigged and ready, for when the fish are marking deep and won't come up.
Line: 50–65 lb braid on everything. Heavier than you might expect for the size of these fish, and the reason is kelp — braid cuts through fronds far better than mono when a fish wraps you up.
Leader: 3 to 4 feet of fluorocarbon, and here's where judgment matters. Run it light, 20–25 lb, when they're finicky in daylight — which is what's been happening lately. Step up to 30–40 lb if they're eating well. Only go 40–50 lb if the fish showing are genuinely big.
The instinct is to fish heavy because it's tuna. Resist it. On a picky daylight bite, the leader is the variable that decides whether you get bit.
Fly-lining the bait
Nose-hook a lively sardine or a mackerel on a 1/0 to 2/0 circle hook, fly-lined with no weight so it swims naturally. Pick the bait that fights you when you reach into the tank — a bait that swims hard behaves like the free food in the chum line. A tired one hangs there and gets ignored.
When it loads up, lean into it. Don't set like a J-hook. This is the mistake that costs more first-timers more fish than anything else. A circle hook needs steady pressure and a turning fish. Swinging on it pulls the bait right out of their mouth.
Keep one rod with a light egg sinker — about an ounce — for when the fish are sitting a little deeper than the surface chum reaches. Small adjustment, big difference on a slow bite.
If the chum isn't pulling them up at all, that's the jig rod's moment: a flat-fall or knife jig in the 150–250 gram range, dropped to whatever depth the boat is marking, and worked back with slow lifts. Same rule on the bite — reel, don't swing.
What's actually out there right now
Honest read on the current grade: the yellowfin showing lately have been more school-sized, mixed in with yellowtail, rather than a thick heavy bite of big fish. That's not a complaint — school-grade yellowfin on light line is genuinely fun fishing, and the mixed bag means you're rarely doing nothing.
But it does change how you rig. With that grade, the smart play is staying on the lighter leader unless you actually see real size showing color at the boat, then bumping up before it gets bitten off. Rigging heavy for fish that aren't there is how you spend the day watching other people hook up.
Trip length, licenses, limits
Which trip? Yellowfin are showing on full-day, overnight, and 1.5-day trips, with longer runs reaching them more consistently. An overnight or 1.5-day gives the boat time to get to the grounds and work multiple paddies. (Not sure what fits you? Here's how to think about trip length.)
Licenses. You'll need a valid California sport fishing license. Many yellowfin trips out of San Diego cross into Mexican waters, which requires a Mexican fishing license — the landing can usually arrange it, but ask when you book.
Limits. Check current CDFW regulations before your trip. Limits and aggregate rules change, and the landing will confirm what applies to your specific trip.
Seasickness. Offshore means open ocean and long run times. Take motion-sickness medication the night before and the morning of. Once you feel it coming on, it's too late.
The bottom line
Yellowfin are the most accessible serious tuna we have, and this year the ocean is set up in their favor.
You don't need to master four techniques. You need to understand what a paddy is, be rigged and ready before the boat stops, run your leader lighter than your instincts want, put a lively bait in the chum line, and lean into it instead of swinging when it loads up. The crew handles the rest.
See who's putting yellowfin on the boards this week on our live fish counts, then find a trip that's running to them. For the full picture of what's biting off SoCal right now, our August forecast breaks down the month.
Tight lines — and go find your next catch.