Not many fish prey on penguins, adult or juvenile. However, sharks may prey on penguins occasionally. This is the case only for tropical penguins, such as those in the Genus Spheniscus.

    As a class of fish, sharks are by and large misunderstood by the general population. Most are small and feed on tiny fish, and even the largest shark - the whale shark - feeds on the smallest of sea creatures.

    However, medium to large sized sharks may on occasion take penguins. The most noted possible predator of penguins is the Galapagos shark (Carcharhinus galapagensis). Galapagos sharks may be found in the three largest oceans, but is usually restricted to the coastal islands. Juvenile Galapagos sharks usually limit themselves even more to the shores of these coastal islands.

    The Galapagos shark ranges from 44 to 136 centimeters in length, with an average representative being 79 centimeters. Galapagos sharks grow very slowly (on the average only 4.1 centimeters per year).

    The Galapagos shark is apparently dimorphic since the male is longer. Socially, the species doesn't seem to exhibit any schooling behaviour or coordinated social or attack behaviour.

Aside: unfortunately, these are not pictures of Galapagos sharks