For big game anglers, fishing for Bluefin and Yellowfin Tuna is as good as it gets. Not only are the two fantastic fighters, but their culinary value is also off the charts. Bluefins and Yellowfins can sometimes look very similar, and on top of that, they often share common habitats. This can make it tricky to tell the difference between Bluefin vs. Yellowfin Tuna. But don’t worry, this quick guide will help you tell them apart in no time.

As you may know, Bluefin Tuna is actually not a single species. It’s a group of five distinct species of fish. These are the Atlantic, Pacific, Southern, Bigeye, and Longfin Tuna. To keep things simple, we’ll focus on comparing the two types of Bluefin that are most widespread and most commonly confused with Yellowfin Tuna. These are the Atlantic and Pacific Bluefin Tuna.

Before we dissect the differences between Bluefin and Yellowfin Tuna, we’re going to take a look at where you can find these fish in the ocean. If you already know which waters your favorite fish inhabits, scroll down to the Appearance section.

Habitat

Yellowfin Tuna

Yellowfin Tuna are widespread around the world. Although they mostly swim beyond the continental shelves, Yellowfins also approach shallower waters when the temperatures are higher. They are often seen prowling around mid-ocean islands. Generally speaking, Yellowfins prefer more temperate waters compared to Bluefins.

In the eastern Pacific, Yellowfins are found around the Hawaiian archipelago, as well as many islands off Baja California. This is why they have become a favorite catch on California long range fishing trips.

On the Atlantic side, you can find Yellowfin from Nova Scotia down to North Carolina. Further to the south, they’re found throughout the Caribbean, as well as around Bermuda, The Azores, The Canary Islands, Saint Helena, and Ascension Island to the east. Yellowfins also inhabit the waters around South Africa and Madagascar, as well as the shores of Western Australia.

Bluefin Tuna

You can find Atlantic Bluefins throughout the Atlantic Ocean. They mostly keep to North America’s eastern coastline, with one portion of the population migrating to the Mediterranean, and the other to the Gulf of Mexico to spawn.

Pacific Bluefins are similarly widespread throughout the Pacific Ocean. As juveniles, they make a long swim from the shores of Japan to the western Pacific. Here, they swim from Washington state all the way down to Mexico. After several years of maturing, they return to the Philippine Sea and the Sea of Japan to spawn.

That’s a lot of information. Let’s sum that up with a visual:

Appearance

Bluefin Tuna grow significantly larger than Yellowfin Tuna. Where Bluefins can reach a massive 1,000 pounds, Yellowfins usually top out in the 400–500 lb range. However, younger Bluefins can easily be confused with their adult Yellowfin relatives. Luckily, there are a few key features that set them apart:

1. The pectoral fin on a Bluefin Tuna does not reach past the beginning of the second dorsal fin. A Yellowfin’s pectoral fin is noticeably longer.

2. The underside of a Bluefin’s body is silver, with uneven lines. On a Yellowfin, the underside is silver as well, but there’s also a distinctive yellow lateral line.

3. The second dorsal fin on a Bluefin is a mixture of gray and yellow. On a Yellowfin, the second dorsal fin is bright yellow.

4. The tail on a Bluefin is dark blue in color, unlike the yellow-and-gray combination on a Yellowfin.

Again, that might be a little difficult to grasp, so let’s take a look at what these differences actually look like. 

Bluefin vs. Yellowfin Tuna Taste

Bluefin Tuna are the most prestigious and luxurious fish money can buy. Because of their delicious fatty meat, they’ve become a sought-after dish in many high-end restaurants. They are the perfect choice for sashimi or Tuna steak. In Japan, a local restaurant chain recently bought a single Bluefin for a whopping $3 million! 

You can mostly find Bluefin Tuna in restaurants these days. Sometimes, you can find Bluefin in supermarkets, but these are likely farmed, lacking the quality and richness of flavor wild-caught Bluefins have.

In comparison to Bluefin Tuna, Yellowfin Tuna meat is leaner, with a lighter taste. While it may lack the coveted fat content of Bluefin Tuna, Yellowfin meat is still of great quality. Yellowfin meat is great for sashimi and steaks. You can also find Yellowfin Tuna in tins. Whichever form you find it in, you’ll notice that Yellowfin meat is considerably more affordable than that of Bluefin.

Conservation

One of the most significant differences between Bluefin and Yellowfin Tuna is their conservation status. While Yellowfin Tuna can be found in relative abundance throughout their range, Bluefin Tuna are a different matter entirely.

Because of their delicious meat, some Bluefin subspecies have been overfished to the brink of extinction. As a result, the International Union for Conservation of Nature (IUCN) has listed Atlantic Bluefin Tuna as “endangered” and Southern Bluefin Tuna as “critically endangered”.

Therefore, if you’re buying Tuna for food, we urge you to always make sure you’re making the most sustainable choice.

So there you have it – now you know how to tell Bluefin and Yellowfin Tuna apart. All you have to do now is catch one!

What’s your favorite Tuna species? Have you ever caught a Tuna? Let us know in the comments below.