Glossary

Dorsal fin

Answer in brief

The fin, or pair of fins, along the top of a fish’s back.

In practice

Spine counts and spots on the dorsal fin settle several lookalike pairs, including the two crappies and walleye versus sauger.

Where it comes up

The linked entry shows the term in use on a real identification problem, and how CatchVault handles that step.

Questions & answers

What is a dorsal fin on a fish?

The fin, or pair of fins, along the top of a fish’s back. Spine counts and spots on the dorsal fin settle several lookalike pairs, including the two crappies and walleye versus sauger.

Sources for this entry

FishBase: Scientific database of fish species, names, ranges and morphology.

Practical guidance is original editorial writing. App details come from the developer’s published descriptions, checked 9 November 2026.

Continue this reading path

Black crappie vs white crappie Glossary CatchVault as a fish identifier

How the related websites connect

This reference is published alongside CatchVault. Species profiles live on the CatchVault website, and sister references cover fishing apps in general and fishing regulations.

Cite this entry

Best Fish Identifier App. “Dorsal fin.” Content reviewed 9 November 2026.

https://bestfishidentifierapp.com/glossary/dorsal-fin/