Telling them apart
Greater Amberjack vs Almaco Jack
Look at the front of the soft dorsal fin. An almaco jack's front lobe is tall and sickle-shaped; a greater amberjack's is low. The body follows — an almaco is noticeably deeper and more compressed at the same length.
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Side by side
| What to look at | Greater Amberjack | Almaco Jack |
|---|---|---|
| Scientific name | Seriola dumerili | Seriola rivoliana |
| Soft dorsal front lobe | Low | Tall and sickle-shaped |
| Body | Long and slender | Deeper and more compressed |
| Eye bar | Dark olive, jaw to front of dorsal | Dark olive, usually more pronounced |
| Amber flank stripe | Distinct on feeding fish | Fainter |
| Depth | Wrecks, ledges and rigs | Usually deeper structure on the same grounds |
| Size | Grows considerably larger | Smaller |
Why the difference matters
Greater amberjack are among the most tightly regulated reef fish in the Gulf and South Atlantic, with short seasons and a large minimum size, while almaco frequently sit under a looser general aggregate. They come off the same wreck on the same drop, so the dorsal lobe is worth checking before anything goes in the box.
Size limits, bag limits, slot limits and seasons are set by your state wildlife agency — and for many offshore and migratory species by federal regulators — and on many waters they differ from the statewide rule. They also change between seasons. Check the current regulations for the exact water you are fishing before you keep a fish — we do not republish limits here, because a number that is a season out of date is worse than no number.
Full entries
Each fish has its own page with every field mark, the rest of its look-alikes, where it holds and the conditions it feeds in: Greater Amberjack and Almaco Jack.
Or skip the key entirely — photograph the fish and Global Fishing League names the species, returns the scientific name with it, and files the catch with the tide, pressure, water temperature and everything else it came from.