Stunning and Strange Starfish!

Who knew that starfish could come in so many shapes and colors ... and with so many arms?!?! Continuing with my recent postings about the wonders of the animal kingdom, today's blog is about starfish!

Starfish, or more technically accurate, sea stars, are fascinating creatures who are amazingly diverse. Most commonly thought of as a five-armed, coastline dwelling animals, starfish come in myriad shapes, sizes, colors, arm counts, and are found from shorelines to the deep sea. About 1,500 species of starfish occur on the seabed in all the world's oceans, from the tropics to frigid polar waters. While they appear to be docile creatures, they can actually be voracious and rather savage predators.

Here are some of the many beautiful, odd and surprising varieties of sea stars around the world.

1.  Leather star (Dermasterias imbricata): Found along the west coast of North America, from Alaska to Mexico, the leather star lives in the seashore down to depths of about 300 feet where it dines on everything from algae to sponges to sea cucumbers. Meanwhile, it does its best to avoid the morning sun star, another species of sea star that makes a quick meal (well, relatively speaking) of the leather star. Leather stars make up to 50% of the diet of the morning sun star.

2.  Morning sun star (Solaster dawsoni): And here is that voracious predator. With anywhere from 8 to 16 arms and usually red or orange coloring, the morning sun star looks...well...like a cartoon sun. It is found in the northern Pacific, from Japan to Siberia and down the coast of North America down to California. Other sea stars literally run away from it if they’re touched by it. Some, however, fight back, including the velcro star and rainbow star which can pinch the morning sun star to make it recoil and provide a window for escape. Other stars have defense mechanisms -- the slime star inflates itself and exudes a noxious mucus, and the sunflower sea star can detach an arm in order to get away. If a morning sun star can’t catch a star of a different species, it has no problem chowing down on an individual of its own species - Hannibal Lecter-style.

3.  Sunflower star (Pycnopodia helianthoides): The sunflower star (above) is the largest sea star in the world, reaching an armspan of 3.3 feet. That space is taken up by 16-24 arms. Their color ranges from bright orange, yellow and red to brown and sometimes to purple. They’re found along the coast of North America, from Alaska to California, but they’re largest in the northern areas. They dine on sea urchins, clams and snails and are usually found in subtidal areas where there is always water, since they can’t support their bodies out of water. Sunflower seastars are quick, efficient hunters, moving at a speed of 3.3 ft/min using 15,000 tube feet which lie on the undersides of their bodies.

4.  Pink short spined star (Pisaster brevispinus): Even starfish look pretty in pink. This sea star can reach a whopping two feet in diameter, and can weigh up to two pounds. It dines on clams and sand dollars, so is usually found on sand or mud, but its soft texture allows it to also grip on coral and rocks where it can feast on mussels, tube worms and barnacles. This is also a celebrity species: Spongebob Squarepants’ neighbor Patrick Star is a pink starfish. So next time you see one, ask for an autograph.

5.  Granulated sea star (Choriaster granulatus): This species goes by many names, including the cushion sea star or doughboy star, for obvious reasons. The plump starfish is found in shallow waters on coral reefs and rubble slopes where it feeds on algae, coral polyps, and scavenges on dead animals. This species is found in numerous tropical waters, including the Great Barrier Reef, Fiji, Red Sea, and Papua New Guinea.


6. Royal starfish (Astropecten articulatus): This vividly colored species (below) is found along the east coast of North America, primarily in the southeast. While it can live at depths of up to 700 feet, it mostly hangs out at around 70-100 feet deep where it dines on mollusks. This pretty star is a carnivore and feeds on molluscs, which it catches with its arms and then takes to the mouth. The prey is then trapped by the long, moving prickles around the mouth cavity. Unlike many other species of starfish, the royal starfish eats its prey whole.

7.  Bat sea star (Asterina miniata): This fascinating species is called the bat star because of the webbing between its arms, which (so some say) look like bat wings. It is found along the west coast of North America, from Alaska to Baja. While the species usually has five arms, it can have up to nine, and it can be a wide range of colors from green to orange to purple. So if you’re wondering if you’re looking at a bat sea star, check if it has the tell-tale webbing.

8.  Crown-of-thorns starfish (Acanthaster planci): The name of this species is fairly clear. The spines covering its upper surface make it look like, well, you know. Those spines are also venomous, which aid it in its quest for world domination. Found over a wide range in subtropical waters, from the Red Sea to across the Indian Ocean, and across the Pacific Ocean to the western coast of Central America, this species preys on coral polyps. As one of the largest starfish in the world, it has a voracious appetitive. When numbers are low, crown-of-thorns starfish help boost the biodiversity of coral reefs by preying on the fastest growing coral species. But if their populations become too high, they can wreak havoc on coral reefs. Their population booms are due in part from human fishing of and collection of their natural predators, the humphead wrasse and triton snail.

9.  Pacific blood star (Henricia leviuscula): Despite the creepy name, this common starfish (below) is actually a very small, slender species that feeds on sponges and bacteria. Meanwhile, its main predators are birds and humans. They are among the most brightly colored sea star species in the intertidal zone and are found at depths of over 1,000 feet.

Don't forget to study for that upcoming test!