One of the numerous sea hares found in the lagoon area

Sea Hare

Sea Hare feeding on algae
Sea Hares are very well camouflaged California Sea Hare California Sea Hare California Sea Hare

California Sea Hare (Aplysia californica)

This is the most common sea slug found in the inter-tidal region. They prefer to graze on specific kinds of red algae. The pigments in the red algae contribute to the overall coloration of the sea hare. These sea hares are particularly difficult to see as they blend into the environment very well.

California Black Sea Hare (Aplysia vaccaria )

this is the largest of all sea slugs. They can grow upwards of 15-30 pounds. They feed on various brown algae in deeper water. They are not commonly seen in tide pools but they can be seen on occasion.
Sea Hare feeding on algae

Navanax ( Navanax inermis )

This sea slug is predatory in that it feeds on other sea slugs, nudibranchs and some snails. The body is generally dark in color with thins blue and orange lines. The body has small white spots. Navanax is typically only a few inches long and found in the water in the lower parts of tide pools, kelp beds and areas with sea grass.

Navanax will track its prey using its keen sense of smell ( chemoreseptors ). The animals will encounter a chemical trail left by a sea slug or other prey item and follow it until it loosed the sent trail ore catches the animal.
Description – Sea Hares are related to snails ( mollusks ) except they do not have an outer shell. They are just like the common garden slugs that devour your backyard plants. The main difference is that they have gills rather than lungs. There are between 60-80 thousand types of mollusks that have been identified. Only three of these are sea slugs commonly found in California tide pools.

Feeding – Most sea slugs feed on specific types of red and brown algae. They use their radula ( sharp mouth parts ) scrape off the algae to feed. Navanax is the only local sea slug that is predatory and feeds on other animals.

Protection – The California Sea Hare has several types of defense mechanisms. The first method of protection is camouflage. It looks very similar to the algae it feeds on and is difficult to see unless it is moving. The second defense mechanism for the California Sea Hare is it can release two types if ink. The first type of ink is a dark purple colored ink similar to squid and octopus. The second form of ink is white in color and will confuse the predator into thinking it is full or no longer hungry. The black sea hare does not have the capability to produce ink.

Ecology – Sea hares are usually short lived and typically life less than a year. They are hermaphrodites in that they are both male and female. They can reproduce sexually when they encounter other animals.
Posted in Animals.

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