Jellyfish. By: Jeff Kuwabara, UHM MOP Coordinator.
PEANUT BUTTE
THE INDISPENSIBLE ROLE ECOSYS
By: Amiti Maloy, U Jellyfish may be transparent in structure, but their value to marine ecosystems is certainly anything but. Jellyfish are made up of a hydrostatic hollow skeleton called the mesoglea. This is a combination of 95% water, as well as collagen, fibrous proteins, and wandering amoebocytes for debris and bacteria collection. This may seem like a strange composition for an animal; however, jellyfish are incredibly unusual- they do not possess a brain, blood, or heart. They are actually a type of zooplankton with an umbrella-shaped bell; the mesoglea creates a light, delicate jelly-like texture that facilitates sea travel. This structure permits jellyfish to go with the flow, drifting with ocean currents. Plankton are a key component in the diets of many marine organisms. Some fish, sea turtles, crustaceans, and even people include jellyfish in their diet. Conversely, jellyfish cannot track their prey; they have to pull in with their tentacles whatever is floating within reach. That said, they have a large stomach compartment that requires frequent refueling. Smaller jellies target miniscule organisms, including algae and zooplankton, while larger species ingest shrimp, fishes, and even other jellyfish. Their constant eating helps control populations of low trophic level species, which is vital to maintaining ecosystem balance. As a simple creature, many jellyfish body parts are multipurpose. For example, the tentacles capture food and aid with movement. The mouth acts as both the entry point for food and the exit for waste. Jellyfish feces becomes fertilizer for plants and small sea creatures in the depths and on the sea floor. This too helps sustain the ecosystem.
Jellyfish bloom. By: UBC Media Relations, Flickr.
14| Seawords
Another special adaptation of jellyfish is their stinging cells, or nematocysts.
