Upside-down jelly
Cassiopea sp.
- Not on exhibit
- Animal type
- Invertebrates
- Ecosystem
- Coastal waters
- Relatives
- Other rhizostomes; Family: Cassiopeidae
- Diet
- Food produced by dinoflagellates called zooxanthellae; zooplankton
- Range
- Tropical waters in the Indo-Pacific Ocean, the Caribbean, Southern Florida and Hawaii (introduced)
- Size
- Up to 16 inches (30 cm) wide and 10 inches (51 mm) high
Meet the upside-down jelly
Down is up for this jelly! They rests their bell on the seafloor and waves their lacy underparts up toward the sun. Why? This jelly is a farmer. Their brownish color is caused by symbiotic dinoflagellates living inside the jelly’s tissues. By lying upside-down, the jelly exposes the algae to the sun, allowing them to photosynthesize. The jelly can sustain themself off just the byproducts of the algae, and can also capture zooplankton for additional energy to grow.
Conservation
Upside-down jellies are more vulnerable than jelly species that live in the open ocean or the deep sea. They live in mangrove forests and shallow lagoons along tropical coasts.
Mangrove forests are among the most threatened ecosystems on Earth; they’re constantly under siege from coastal development or questionable farming practices. People clear mangroves to build hotels, housing, and fish farms. Pollution flows into mangrove forests from these coastal developments, endangering all life in this rich forest habitat.
Cool facts
- This jelly is rarely found alone; they flip upside-down alongside others of their kind.
- Turned upside-down with stubby oral arms pointed toward the sun, the jellies look like flowers.
- Upside-down jellies can grow to the size of a pie plate.
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