Seal

Seals are a widely distributed and diverse infraorder of carnivorous, fin-footed, semi-aquatic, and mostly marine mammals and live in the oceans of Narnia.

The Voyage of the Dawn Treader (The 4D experience)
Like the whales, the seals are seen multiple times during ocean scenes.

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 * California sea lion
 * Grey seal
 * Harbor seal
 * Walrus