Which feature is characteristic of fin whales for identification?

• A. Common dolphin, white-sided dolphin
• B. 10 knot speed limit zones, 500 yard exclusion
• C. Asymmetrical jaw coloring
• D. Small size, pointed snout

Answer: (C)

Identifying fin whales at sea often hinges on distinctive color patterns around the mouth. A telling field mark is that the lower jaw coloration is asymmetrical—one side differs from the other. This kind of uneven jaw coloring helps you pick out fin whales from other large baleen whales that tend to have more uniform jaw coloring, and it’s not something you’d use to identify dolphins or rely on for regulatory zones. The other options don’t describe whale anatomy: a reference to different dolphins, a regulatory rule, or a general small size and pointed snout don’t fit fin whales. So this asymmetrical jaw coloring is the feature to look for.