when males and females spawn their 

 eggs and sperm in the water. The 

 fertilized eggs develop into free- 

 swimming larvae, which metamor- 

 phose into miniature starfish. But if 

 you cut a common starfish into parts, 

 you could create five new organisms. 

 When a starfish loses an arm, a new 

 one will begin growing within days. If 

 the arm is still attached to a part of the 

 body core, it can produce a new 

 starfish. Some species even reproduce 

 by breaking apart and slowly regener- 

 ating an entire body from a single arm. 



Starry-eyed beachcombers 

 scan the shores for a whelk's shell, 

 a blue mussel and — 

 if they're really lucky — 

 the starfish. 



Although the starfish looks rigid, 

 it's actually flexible — watch a 

 starfish flip its arms underneath its 

 body to turn upright after a spill. The 

 duality stems from calcareous plates, 

 which cover the body and act like a 

 suit of armor. These plates are 

 protected with a thin layer of skin 

 cells that are covered with cilia, tiny 

 hairs to sweep away dirt and debris. 

 The plates are also coated with 

 knobs or spines, which 



illlllllllft5&, vary in shape, 

 color and 



size depending 

 on the species. 

 Peeking out between the 

 plates are skin gills — 

 bumps of skin exposed to the 

 ocean environment. These 

 take in oxygen and 

 give off carbon 

 dioxide. Some j 

 types of 

 star- 



fish also have 

 pedicellarias, tiny pincers 

 that crush whatever 

 crosses their path. 



All starfish are 

 successful scavengers 

 and predators. Some 

 attack mollusks, 

 some feed on dead 

 fish and others take 

 in organisms from seawater. 

 Pincer-carrying starfish, such as the 

 Asterias forbesi, can consume massive 

 amounts of shellfish, much to the 

 dismay of oystermen. 



In class, Kirby-Smith likes to 

 compare the eating habits of the 

 Asterias forbesi with another starfish 

 common to North Carolina — the 

 Astropecten. 



Asterias moves from 

 oyster bed to oyster bed 

 by curling up on the tips 

 of its arms and floating with 

 the tide. Some oyster beds 

 have been reported to contain 

 more than 1,000 starfish. In the 

 early 20th century, oystermen 

 would rip up the starfish 

 to kill them, unknow- 

 ingly multiplying 

 their problem. 



* m^. to 



feed, the 

 Asterias 



mounts a mollusk and tugs on the 

 tightly shut shell with its tube feet. It's 

 said that when an Asterias pops open 

 a large clam, it applies 12 pounds of 

 pressure. When the shell opens just a 



Luiclia clathrata, grey sea star 



crack, the starfish everts its stomach 

 through its mouth and into the mollusk. 

 digesting the animal. 



The Astropecten, on the other 

 hand, consumes organisms whole, 

 spitting shell or debris from its mouth. 

 These starfish consume tiny organisms 

 — anything a few millimeters in size, 

 including others of its species. The 

 Astropecten is covered with a special 

 spine that "looks like the canopy of the 

 rainforest," says Kirby-Smith. The 

 branches of the "trees" protect the body 

 from sand and other debris. 



One thing Kirby-Smith wants to 

 see investigated is the status of the 

 common starfish Asterias forbesi. He 

 believes this starfish is becoming more 

 scarce for unknown reasons. 



But most starfish live uncontrover- 

 sial, secluded lives. Starfish have few 

 natural enemies, and the once irate 

 oystermen have all but lost their 

 industry to pollution and disease. 

 Except for tourist shop trinkets, 

 there's no commercial demand for 

 starfish. And outside of class discus- 

 sion and dissection, says Kirby-Smith, 

 there is little search for new starfish 

 information. 



For starry-eyed beachcombers, 

 however, the quest is always on. They 

 scan the shores for a whelk's shell, a 

 blue mussel and — if they're really 

 lucky — the starfish. □ 



COASTWATCH 15 



