Species · GBIF taxon 2264506
Blue Blubber Jellyfish
Catostylus mosaicusAlso known as Jelly Blubber, Blue Blubber, Mosaic Jellyfish
Blue blubber jellyfish drift through coastal estuaries and shallow bays in massive, spectacular swarms, pulsing their dome-shaped bells in a distinctive staccato rhythm. Lacking a central mouth, they use tiny openings on their eight highly branched, cauliflower-like oral arms to capture microscopic plankton. Their coloration varies dramatically from creamy white to deep blue or purple, a hue influenced by symbiotic algae living within their tissues.
MarinePlanktonicStinging
Licensed referenceVia Fernandez / CC BY-SA 3.0 · cc-by-sa
—observations
—countries
—peak records
Not EvaluatedConservation statusIUCN Red List categoriesLCNTVUENCREWEXNot Evaluated — not placed on the risk ladderRed List categories, explained →
Diet & prey
- Copepods
- Fish Larvae
- Microalgae
Predators
- Leatherback Sea Turtle
- Ocean Sunfish
- Nudibranchs
ThreatsCoastal development, water pollution, and marine debris
HabitatsEstuaries, coastal bays, and shallow marine waters
Life spanUp to 1 year
Size / weightNot available
Classification
- FamilyCatostylidae
- SpeciesCatostylus mosaicus
Range data is not available yet.
Interaction riskVery high
- Low
- Moderate
- High
- Very high
- Why interaction risk is very high
- Delivers a mild sting that can cause minor skin irritation; avoid direct contact with tentacles.
- Why it is dangerous
- Possesses stinging cells called nematocysts on its oral arms that deliver a mild, irritating venom.
- How to recognize a risky encounter
- Look for a large, smooth, dome-shaped bell ranging from creamy white to deep blue, lacking long trailing tentacles.
- What to do
- Do not touch live or washed-up specimens; if stung, rinse the area with seawater and apply a warm compress.
Responsible observation
- Observe from above: Watch their rapid, staccato pulsing behavior from a pier or boat during summer blooms.
- Keep your distance: Avoid swimming directly through dense swarms to prevent accidental stings.
- Look for hitchhikers: Search closely around the bell for small juvenile fish seeking shelter among the arms.
Close Relative Cape Hatteras National Seashore / Public domain · cc0
Rhizostome Relative (c) Thibaud Aronson, some rights reserved (CC BY-SA), uploaded by Thibaud Aronson · cc-by-sa
Image unavailableRhizostome Relative
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