The moon jellyfish, also known as the common jellyfish (Aurelia aurita) is a species of jellyfish found in every ocean but the Arctic. There are many species of moon jellies within the genus Aurelia, and most are functionally very similar. A. aurita are especially common among the coasts of North and South America and Australia, where they frequently wash up on beaches. They prefer warmer shallow waters around 18C, and require a salt content of at least 0.6%, although they can survive in a wide range of temperatures and salinity, and have been found as deep as 1,000m.
As jellyfish, A. aurita have no internal organs and exhibit radial symmetry, or symmetry around a central axis. The outer bell is transparent, ranging from 10 to 60 cm across. This bell also acts as a membrane through which moon jellyfish absorb oxygen, digest food, and move their bodies. Beneath the bell are distinct, colored veins which act as a reproductive organ. Most moon jellyfish have 4, but some individuals can have more. Small, non-stinging tentacles line the outer bell, and on the underside are 4 arms which stun and collect prey such as plankton, copepods, mollusks, fish larvae, and smaller jellyfish. Although they posess no caloric value, they have high amounts of fatty acids which makes them prime prey for seabirds, turtles, fish, and larger jellyfish.
Most moon jellyfish only live 2 years in the wild, though in captivity they can live up to 25 years. They reproduce sexually, although they exhibit no courtship behaviors. Male A. aurita release their sperm into the water, where they are carried by currents into the gastric pouch of female jellyfish and fertilize their eggs. These eggs are then re-released into the water. After 10 days the eggs hatch into a larval stage called a planula which settles onto the ocean floor and form polyps. These polyps can form buds that break off and form individual jellyfish through a process called strobulation. The whole process takes about 4-6 months, and usually begins in the summer when most mating occurs. However, A. aurita is capable of reproducing year-round and will do so whenever conditions are good.
Conservation status: The moon jellyfish has not been rated by the IUCN. However, in many places it is considered invasive; when resources are plentiful, populations can explode leading to diminished resources for other animals and increased bacteria levels in the water.
Polypodium hydriforme is one species of cnidarian so different from the other cnidarians it’s just its own thing, like you can split cnidarians into corals, jellyfish and a few other groups and then this group is just the one species here.
And it’s a parasite that grows in salmon eggs!!! These photos are what it looks like in its free living stage where it just keeps multiplying in blobs. when they develop in a salmon egg all their tentacles are pushed in, like if you pushed in all the fingers in a rubber glove, and as they hatch they flip all their tentacles out but this action sucks all the salmon yolk into them and then that’s their food for the rest of their life.
Edwardsiella andrillae, an Antarctic species of sea anemone that lives upside-down, burrowing into the sea ice and projecting its tentacles into the frigid water below.
The weird and wonderful pom-pom anemone rolls across the deep seafloor.
Pom-pom anemones, Liponema brevicorne, are amazing and adaptable invertebrates. This anemone resembles an unusual tentacle-covered dome unlike the more common stalked column body associated with many other anemones. Even within the unique body shape, there is variability. Sometimes it is observed in a low, deflated position, while other times it is puffy with tentacles extended.
While other species of anemones stay attached in one place, pom-pom anemones can be mobile. Using their muscles, they can contort their body into a barrel-like shape. They roll across the seafloor like a tumbleweed in the desert, propelled by ocean currents. It is speculated that this behavior allows them to scavenge and seek out more nutritious habitats in search of plankton and small crustaceans.
Liponema may be an important link for other animals, both in terms of habitat and as a food source. Shrimp, amphipods, and even fish have been observed using these anemones as shelter among the relatively flat, muddy seafloor. MBARI researchers have also found that pom-pom anemones may be an important source of food animals such as sea spiders, or pycnogonids. The sea spiders appear to suck material from the anemone’s tentacles. Luckily for pom-pom anemones, this does not appear to harm them. In fact, pom-pom anemones can shed tentacles, giving spiders an on the go treat.
While spending time in Australia, I went to Manly Beach to surf. I saw all these poor washed up blue bottle jellies, and felt kinda bad for them. That was, until I got stung. A wave had brought one up to my ankle. I suddenly felt a strange stinging sensation, so I looked down and saw a skinny, long, blue tentacle wrapped around my leg. Let’s just say I don’t feel as sorry for the little buggers now.
Immunostaining of planktonic Cnidaria. Acetylated tubulin (green), myosin (red), nuclei (blue). Image taken with ZEISS Lightsheet Z.1 during the EMBO course on Marine Animal Models in Evolution & Development, Sweden 2013. www.zeiss.com/lightsheet Sample courtesy of Helena Parra, Institut de Biologia Evolutiva (CSIC-Universitat Pompeu Fabra), Barcelona.
Getting ready to celebrate Mother’s Day this weekend? Meet Big Momma, one of the largest coral heads in the world found in National Marine Sanctuary of American Samoa!
The snail in this photo is identified as either Harpovoluta charcoti,Provocatorsp., or Provocator corderoi. The sea anemone (Isosicyonis alba) is probably always attached to a gastropod snail, and it occurs in the Antarctic, in the southern Atlantic, and South Chile.
Derelict fishing gear and other marine debris smother existing animals and create an unstable habitat for those organisms that survive the initial impact. Here some examples of litter items on Condor seamount, west-southwest of Faial Island in the Azores, and interactions with local fauna.
A) close up of a Dentomuriceacf. meteor entangled within a longline
B)glass bottle next toDentomuriceacf.meteor
C)lost wooden box used by fisherman to hook their longlines
D) several Dentomuriceacf.meteor partially damaged
The Psychedelic Medusa is a deep-sea hydrozoan that is abundant in the North Pacific. The mini-jelly is found at depths between 1000m to 3800m, and are often observed drifting near the ocean floor. It also has an eccentric reproduction behavior uncommon in cnidarians. The females display viviparity, and carry the babies in her bell until they are ready to hatch.
Crab walks around with Jellyfish on its back to protect it from predators
These #jellyfish Cassiopea (upside-down jellyfish) partake in a symbiotic relationship with photosynthetic dinoflagellates and therefore, must lay upside-down in areas with sufficient light penetration to fuel their energy source. Where found, there may be numerous individuals with varying shades of white, blue, green and brown.
Sometimes this jellyfish is picked up by the #crab Dorippe frascone and carried on its back. The crab uses the jellyfish to defend itself against possible predators.
