Side by Side

Albacore Thunnus alalunga

Typical: 26–34 in, 15–30 lb

Key field mark: Albacore's pectoral fins are exceptionally long (reaching past the second dorsal and anal fins) and the tail has a clean white trailing margin — both unique among the local tunas.

• Steel-blue back grading to dusky silver sides
• Extremely long pectoral fins reaching past the anal fin origin
• White trailing edge on the tail (caudal) fin
• Rounded football body with a relatively small second dorsal
• Finlets dusky/dark, not bright yellow

Full Albacore guide — season, gear and rules →

Bigeye Tuna Thunnus obesus

Typical: 40–60 in, 60–150 lb

Key field mark: A large eye plus a long pectoral fin AND short (un-elongated) second dorsal and anal fins separate bigeye from yellowfin; note the liver is SMOOTH (only bluefin has a striated liver), so dockside rely on the big eye and the long pectoral with short median fins.

• noticeably large eye
• very long pectoral fin (reaching past the second dorsal, especially in smaller fish)
• short second dorsal and anal fins (never elongated)
• dark metallic blue back, whitish belly
• bright yellow finlets edged in black

Full Bigeye Tuna guide — season, gear and rules →

When Each Is Running July — current month highlighted

Where Albacore and Bigeye Tuna Overlap

Both run in Southern California — that is where telling them apart actually matters.

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