Robert P. Hill, age 10, of Winston Salem, North Carolina, for his question:
What do shrimp eat?
We can call him omniverous because he eats a mixed diet. Nearly 8,000 shrimp species have been named and no doubt more are still in hiding. Post species belong to the sea. There they perform valuable clean up duties and the place would be a mess without them. They also play a key role in the great food chain that supports every living thing in the hungry sea. And every year, about 100,000 tons of delicious, nutritious little shrimp are captured and become human food.
Fresh water shrimp gobble up the eggs and larvae of aquatic insects, also small swimmers and various other water dwellers, alive or dead. They also eat water weeds, alive or dead. Some species scrounge a living in brackish bays and inlets. But most species thrive in far greater numbers in the salty sea. Often zillions of them travel together, crowding the shallow coastal waters or venturing far out into the realm of the deep ocean. They are very noisy hunters, clicking and clacking their joints as they go.
Life in the hungry sea tends to be fast and short. Even the seaweeds grow, live and die at a great rate. Large fish are messy feeders that strew the water with uneaten_portions of their victims. If this stuff had time to decay, it would turn the sea into smelly soup. But the leftovers are promptly devoured by hordes of hungry shrimp and other aquatic diners.
They also enjoy fresh algae, which prevents these fast growing seaweeds from suffocating, themselves. They devour enough small swimmers to prevent various fishy population explosions. By eating their mixed diets, the shrimp help keep the seawater clean and also help nature reduce numbers so that there is enough food to go around.
A coral reef would be a miserable mess without several special cleaning shrimp. These dainty midgets feed on the pesky parasites that infest the teeth and scales of their larger neighbors. One lives safely among the stinging tentacles of a giant sea anemone. He earns his lifetime rent by cleaning and manicuring his huge host. The dainty barbershop shrimp, naturally striped in red and white, runs his cleaning business from a pocket in the hard coral.
When a customer signals for service, the shrimp scuttles out to remove his irritating parasites. One fishy customer signals for service by changing color. One stands on his head. The moray eel opens his jaws and the shrimp removes bothersome bits from between his teeth. Sometimes this chump snaps shut and eats his little dentist.
The shrimp is a crustacean with a thin, crunchy coat. With the crusty crabs and lobsters, he belongs in the ten legged decapod order. He may be some shade of plain or freckled brown, tinted with pink or almost glassy clear. His long skinny legs and antennas give him a whiskery look. His two front legs are sturdy pincers. He uses them as weapons and to tear large hunks of food into swallowable bites.