How to start identifying the fish you catch

These words help you describe a fish or understand a picture:

• Body shape: long and narrow, rounded, or tall from back to belly—often called deep-bodied.
• Mouth: its position and shape, seen without opening or handling the fish to inspect it.
• Dorsal fin: the fin or fins along the back.
• Pectoral fins: the paired fins near the sides behind the head.
• Tail fin: the fin at the rear. A forked tail has an inward notch between two ends; a rounded tail has a curved outer edge.
• Markings: spots, bars, stripes or patches, including exactly where they occur.
• Barbels: whisker-like feelers around the mouth on some fish.

A note such as “one dark spot near the tail” is more useful than “a spotty fish.” It gives you a feature and a location to compare. It still isn't an identification on its own.

Start with the overall body shape, then compare the fins and markings with a reliable guide. Choose a possible name, read its description and check the similar-looking species too. If a feature doesn't match, keep comparing instead of choosing the nearest-looking picture.

For an illustrative comparison, a tail-area spot may match a candidate description while a folded fin leaves another important feature unseen. Keep the candidate open and ask what else distinguishes it from similar species; don't count the unseen fin as a match. Color alone can be misleading. Record a feature the view doesn't show as unknown rather than absent.

Read the written description as well as the picture. Keep a conflicting feature visible in your note instead of dropping it to make the closest-looking image fit. If the reference or available view cannot settle the distinction, carry that uncertainty to the crew or appropriate identification help before a keeping decision.

The place matters too: name the lake, river or coastal area, rather than only the town where you're staying. Freshwater has little salt; brackish water is a mix of fresh and salt water. Location gives context, but doesn't prove the identity by itself.

Start with LDWF's saltwater fish information or freshwater fish information for the relevant water. LDWF is the Louisiana Department of Wildlife and Fisheries.

Anglers may use a familiar local name instead of the name in a reference. For example, redfish commonly means red drum, and speckled trout means spotted seatrout in Louisiana fishing conversation.

Keep the nickname and proposed full name distinguishable until the identification is confirmed. Then write down the full reference name. Don't assume a nickname used elsewhere means the same fish, or that everyone saying “trout” is referring to the same species.

On a guided trip, ask: ‘Which features tell you that's this fish rather than a similar one?’ Then look for the features the guide names. For your own learning, the fish-guide directory connects common names with beginner introductions; use the responsible reference to resolve an identification before relying on it.

When a photo is appropriate, try to include the whole side of the fish: head, body, fins and tail. A close-up of the face may hide the feature you need later. Add the place, date and a short note such as ‘one spot near the tail; fin folded in photo.’ That separates what you saw from what the picture can't show.

A brief learning note can keep five things together: actual water and date, visible features and their locations, features not shown, possible full name with the reference used, and the question still unresolved. Mark the name as possible or confirmed rather than let a photo filename become the answer. For the folded-fin example, ‘fin not visible’ remains part of the record until suitable evidence resolves it.

Ask the crew to help with positioning and handling. Don't prolong handling or spread sharp fins with your fingers just to improve a photograph. A picture for later learning isn't a reason to improvise with an unfamiliar animal.

Once the species is confirmed, use that name to find the current rule for the water and activity. Then read the size, date, count and other conditions in the entry. A name match doesn't answer those separate questions. Keep the basis for confirmation separate from the rule entry: who or which reference helped resolve the identity, and which official entry applies to that confirmed species and actual outing. A guide's nickname or an earlier trip's rule note isn't a substitute for those two checks. The catch-rule lesson explains the process.

Ask the crew before deciding to keep an uncertain fish. If you're fishing independently, learn the likely species and appropriate handling before the outing, and don't turn a guess into a keeping decision. Use each uncertain encounter as a learning question: which feature was missing, what similar species needed comparison and what evidence would distinguish them? That helps with the next reference check without turning an incomplete encounter into a confirmed species record. This page introduces observation; it isn't a complete identification key or a current rule table.