Snails, Limpets, and Octopus

 
 Moon Snail  (Polinices lewisii)  
 Moon Snail Description: Large white to tan shell, with enormous translucent pink to brown foot. The snail pumps water into its mantle and foot, increasing its mass to 3 or 4 times that of just the shell alone. When threatened, the snail pumps the water out of its body, pulling entirely inside the shell, and sealing the shell with a brown door-like operculum. Common in sandy and rocky intertidal. Up to 5.5 inches high.  
 Food: This snail is one of the top predators of the intertidal environment. Chief among the Moon Snail's preferred foods are clams. The snail surrounds the clam with its foot, then drills into the clam shell with a radula, which is covered in tooth-like rasps. Weak acids also are excreted onto the shell, hastening the drilling process. Once the characteristic hole is made, near the clam's hinge, the snail injects digestive enzymes into the clam. When ready the snail scrapes, and sucks out the meat from the clam, leaving an empty clam shell behind. An adult Moon Snail can eat a clam every 4 days.  
 Reproduction: Female lays eggs in distinctive round moulded sand collar. Made of a layer of sand, then a layer of tiny eggs, and then another layer of sand, the whole egg collar is held together with snail mucus. Eggs are laid in spring through fall, and the 100,000 eggs in each collar hatch out in about 6 weeks.  
 Fun Facts: Besides humans, gulls are the chief predators on the Moon Snail. A gull will pick up a snail and carry it aloft, and then drop it onto the rocks to break open the shell.  

 

 Checkered Periwinkle  (Littorina scutulata)  
 Periwinkle Description: Brown or black elongated shell checkered with white spots. Found on seaweed, or rocky shorelines in high intertidal zones. Can survive long periods out of water and are thought to be the ancestors of all land snails. Good eyesight, with eyes perched on long stalks. Length to about 0.5 inches.  
 Food: These snails use a long radula with up to 300 "teeth" to scrape algae off the rocks.  
 Reproduction: Separate sexes. Females lay eggs.  
 Fun Facts: When holding a periwinkle in ones hand, if one hums to the snail steadily for a minute or two, the snail will come out of its shell and begin crawling around.  

 

 Purple Whelk  (Nucella lamellosa)  
 Welk Description: A relatively large heavy bodied snail often with a shell covered by frilly ridges. In exposed areas the smooth form is encountered (shown at left). Color can vary from white, to purple, yellow, orange and others. Found throughout all intertidal zones on rocks, mussel beds and barnacles. Length to over 3 inches.  
 Food: Feed on mussels and barnacles, drilling a hole with a radula.  
 Reproduction: Females can lay up to 1000 eggs per year, with the eggs resembling yellow oat kernels, leading to their common name, "sea oats."  
 Fun Facts: These snails are eaten by the Red Rock Crab, and Mottled and Ochre Sea Stars.  

 

 Red Octopus  (Octopus rubescens)  
 Red Octopus Description: A small octopus sometimes found exposed or under rock in the intertidal zones. Eight arms, well developed eyes, and a parrot-like beak under the mantle. Suction cups on each arm. Very intelligent. Rough unfolded skin. Color dull red, to reddish brown, can be mottled with white (see below). It can make its den under a rock, in an empty Moon Snail Shell, or even in an empty bottle. Mantle grows to 4 inches. Arms can reach 16 inches long.  
 Food: Hunts crabs and other invertebrates.  
 Reproduction: Separate sexes. Specially developed arm on males delivers sperm packet to female.  
 Fun Facts: This octopus can change color rapidly when disturbed. It can change between bright red, brown, white, speckled gray and black all within a matter of seconds. This ability to change color is useful for defense, and in hunting, but many researchers believe these color changes are an indication of emotional state of this intelligent little animal. This animal has a venomous saliva which it injects with its bite. If found on the beach, do not handle.  

 

 Limpet Group    
 Limpet Group Description: Limpets are mollusks with only one cone-shaped shell (valve), and a suction cup like foot. A ribbon-like radula covered in rasps scrapes algae off the rocks on which it makes its home. Well developed eyes and tentacles. The intertidal limpets are highly territorial, and will defend their home against competition. Most average about 1 inch in diameter.  
 Food: Grazers. Radula scrapes algae off rocks.  
 Reproduction: Lays eggs.  

 Fun Facts: Some limpets will spend their entire lifetime, up to 20 years, on a single rock!

 

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