Get ready to be fascinated by the blue button jellyfish – a tiny yet mesmerizing creature found in warm coastal waters worldwide. But here’s the catch: it’s not even a jellyfish! Are you ready to discover more fun facts about this master of disguise and its essential ecological role in the ocean in this short article?
Phylum: Cnidaria
Class: Hydrozoa
Order: Anthoathecata
Family: Porpitidae
Genus: Porpita
1. It’s similar, but it isn’t actually a jellyfish
Although being called the blue button jellyfish, this species is not. Instead, it’s similar to the Portuguese man o’ war. The creature is classified as a hydroid and is a colonial animal that is made up of different zooids.
Blue button jellies are quite small, measuring roughly 1 inch in diameter. They consist of 2 parts: the float and the hydroid colony. The float is disc-like in shape with a golden brown center. It is wrapped by numerous tentacles that are blue, yellow, or purple. These tentacles are different hydroid colonies.
Each zoid within the colony has a separate purpose, such as reproduction, hunting for food, or digestion. Despite their different functions, they all float together on the water’s surface.
The tentacles of blue buttons are equipped with nematocysts, which are stinging cells found at the end of the knobs.
2. They don’t swim, they float
Blue button jellyfish are marine creatures that drift freely on the surface of the water. Due to their gaseous bodies, they are lightweight and can’t swim deep like actual jellyfish. As a result, they are easily carried away by tides, wind, and sea currents, sometimes washing up on shore in large groups.
These organisms are typically found in warmer waters, including the Indian, Pacific, and Atlantic Oceans, as well as the Mediterranean and eastern Arabian Seas. Blue buttons also live in the southern regions of the United States, such as the Gulf of Mexico, as well as in New Zealand and other locations. In Europe, they primarily inhabit warmer regions.
3. Diet
These creatures are carnivorous and eat a variety of small organisms, such as copepods, plankton, crustacean larvae, and other floating organisms.
While the man-of-war passively gets food, these blue button jellyfish actively hunt for their food. They also compete for food with other passive organisms.
These jellyfish are targeted by several predators, including the violet snail, the blue dragon Glaucus, and other sea slugs.
4. They excrete through their mouth
One of the awkward things about these species is that they have a dual-purpose mouth. It serves for both consuming food and excreting waste. This mouth is located beneath the float.
Doesn’t that sound disgusting? But, in the animal world, this is pretty common. Species such as sea sponges, sea anemones, and jellyfish also have a specialized mouth like this. Without an anus, they have to discharge waste through their mouths.
5. They can reproduce on their own
Similar to sea slugs, blue button jellyfish are hermaphrodites, possessing both male and female sex organs. However, the difference is that they don’t have to find a mate like those slugs. They are capable of self-fertilization.
To reproduce, the reproductive polyp discharges eggs and sperm into the water. These eggs and sperms combine to form a fertilized egg – a new polyp. This fertilized egg undergoes metamorphosis and grows into a specialized polyp.
The polyp then divides to generate multiple polyps with distinct functions. They then come together to create the colony called the blue button jellyfish.
6. They can sting you
Like the man-of-war and jellyfish, blue button jellyfish can sting you. Porpita porpita sting is not as painful and dangerous as the sting of the other two, but it can still trigger allergic reactions.
Although it’s common for these creatures to wash up on beach shore, it’s recommended that you avoid contact with them, even if they are dead. If you are stung, slowly remove the tentacles from your skin by using a towel or gloves. Do not do this with your bare hands.
To soothe the affected area, you can apply a cold compress containing vinegar or lemon, if available. Then you should seek medical attention promptly to prevent further inflammation.
7. Threat
Due to their preference for warm temperatures, the population of these organisms has increased. This causes them to appear in previously uninhabited areas and leads to ecological imbalances.
The proliferation of ocean plastic pollution has had a significant impact on these organisms. This is because many small crustaceans become trapped in plastic containers, reducing their food supply. Additionally, larger animals that consume these organisms can mistake plastic bags for their prey due to their semi-transparent nature.
The problem is further exacerbated by industrial fishing practices. These blue button jellyfish are hauled into the trawler and are also caught to feed human fish pets.
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