November 30, 2011
Upside-down sea jellies are now on display in the Jewels of the Pacific exhibit in the Aquarium’s Tropical Gallery. These unusual sea jellies spend most of their lives attached to the sea floor with their tentacles pointed up toward the ocean’s surface. Symbiotic algae live in the jellies’ tentacles. Because the jellies’ tentacles are aimed at the sun, the algae are able to photosynthesize and produce food for the jelly. Upside-down jellies also capture microscopic animals for food using stinging cells released from their tentacles.
These jellies live in mangrove forests and shallow tropical lagoons in the Indo-Pacific Ocean, the Caribbean, Southern Florida, and Hawaii. They can reach up to a foot in diameter. Many animals prey on upside-down jellies, including ocean sunfish and leatherback sea turtles. The stinging cells the jellies use to capture prey can also be used to ward off predators.