1. Jellyfish Golda Gozum M.L. Anderson, 2009

2. What is a Jellyfish? Jellyfish are invertebrate species of sea dwelling animals that are so named due to their gelatin-like bodies. Jellyfish are not fish.Jellyfish are invertebrate species of sea dwelling animals that are so named due to their gelatin-like bodies. Jellyfish are not fish.

3. Cnidarians The word Cnidarian comes from the Greek, “cnidos” which means “nettle”. Nettles, or nematocysts, are stinging cells, and all Cnidarians have them. These are some of the oldest, largest and most poisonous creatures on Earth. Red striped sea nettle

4. There are four major classes: Hydrozoa – Hydroids, Siphonophores Scyphozoa – True Jellyfish Cubozoa – Box jellyfish Anthozoa – Sea anemones and Corals (Discussed in a different presentation) Scyphozoa Staurozoa Cubozoa Hydrozoa

5. There are about 10,000 species. Scyphozoa with @ 200 species, Staurozoa @ 50 species, Cubozoa @ 20 species, Hydrozoa @ 1000-1500 species. Ancient, simple animals. Fossil records date back to the Precambrian Era, 550mya. Cnidarians Cambrian Period; 540 mya

6. A typical jellyfish body is composed of the bell, the oral arms or feeding arms, and the tentacles. There are some species that do not have tentacles. Jellyfish come in a big variety of colors like white, blue, pink, yellow, green, purple, red, orange, and striped. The bright colors and tell their enemies that they are dangerous fish. Box Jellyfish Purple striped Jellyfish Jellyfish Features

7. Ancient, simple animals. Fossil records date back to the Precambrian Era, 550mya. There are about 10,000 species. Size ranges from a few mm to over 30m. All are predators and carnivores. They spend their lives in sessile polyp forms, as free-swimming medusa, or both. As polyps the tentacles point up, as medusa the tentacles point down. They have both asexual (polyps) and sexual (medusa) reproduction. Jellyfish Features Red striped sea nettle

8. Jellies go through several different body shapes in the course of their life..Jellies go through several different body shapes in the course of their life.. Adult, free floating medusas produce eggs and sperm.Adult, free floating medusas produce eggs and sperm. Newly hatched larvae float in the currents until they find somewhere to attach.Newly hatched larvae float in the currents until they find somewhere to attach. After a short time living attached to a hard surface, the polyp divides into many ephyrae, which peel off and float away.After a short time living attached to a hard surface, the polyp divides into many ephyrae, which peel off and float away. Ephyrae float and feed and grow until they are medusas, and the cycle starts all over again.Ephyrae float and feed and grow until they are medusas, and the cycle starts all over again. Life Cycle

9. Location Jellyfish live in oceans throughout the world. Few species inhabit saltwater lakes. Some jellyfish prefer warm, tropical waters while other species prefer cold, arctic waters. Jellyfish live in many oceanic zones, from shallow inshore waters near coastlines, to open ocean. They survive at a variety of depths, some species inhabit the top level of water while others inhabit darker, deeper depths.

10. No head, skeleton, or special organs for respiration and excretion. No head, skeleton, or special organs for respiration and excretion. Stings vary in potency – mild to very potent. Stings vary in potency – mild to very potent. Range in size from 12mm to 2m across. Range in size from 12mm to 2m across. A group of jellies is a ‘smack’ A group of jellies is a ‘smack’ Alternates between sessile polyp and free-swimming medusa. Alternates between sessile polyp and free-swimming medusa. Scyphozoa – True Jellyfish

11. It resembles a jellyfish but is actually a colony of specialized individuals, such as the deadly “Portuguese Man-of- War”. Nutrients are shared through a collective gut system. Other hydrozoans form massive colonies that resemble coral, but are not, such as the highly toxic “fire corals”. Hydrozoans alternate between sessile polyp and free-swimming medusa stages. Siphonophores

12. They look like basic jellies but are box shaped. Tentacles are on each corner of the box shaped bell They have well-developed eyes They have a simple brain Unlike other drifting jellies, box jellyfish are strong swimmers Also called sea wasps There are about 20 species in tropical waters Some are highly toxic Cubozoa – Box Jellyfish

13. They are responsible for helping maintain balance in the delicate ecosystem of the ocean. Since jellyfish are a kind of plankton, they have a direct effect on the food supply in the deep sea.

14. Jellyfish are carnivorous. They eat mostly zooplankton, smaller fish and sometimes other jellyfish. Bigger jellies eat large crustaceans like shrimp and other sea animals. Importance

15. Jellyfish have an incomplete digestive system, meaning that the same orifice is used for both food intake and waste expulsion.

16. They are often eaten by sea turtles, sunfish, and spadefish. Crabs and other large crustaceans also snack on jellyfish, too. In some Asian countries, even people eat jellyfish.

17. Seafloor habitats are being destroyed by overfishing, rising water temperatures and decreasing marine biodiversity, and reducing the ability of the seas. This could make way for increasing invasions of jellyfish and microbes. Jellyfish compete for many of the same food sources as fish, so fewer fish in the seas means more room for jellyfish. Environmental Concerns

18. Increasing numbers of fishermen nets are filling with jellyfish, which slime, poison, and crush the intended catch. Jellyfish are changing ecosystems, stinging beachgoers, and causing millions of dollars worth of damage. Environmental Concerns

19. Fun Facts The box jelly fish contains a venom which is the strongest venom throughout the entire animal kingdom.

20. Fun Facts Lions Mane Jellyfish, largest known jellyfish. It can grow up to 7 feet and its tentacles can reach up to 120 feet in length.

21. The Moon Jellyfish is the jellyfish that is usually washed up on beaches during the summer high tides and winds. By the time the Moon jellyfish is washed up on the beaches, the tentacles are gone and these jellyfish are harmless. Moon Jellyfish