HomeЖивотныеRelated VideosMore From: lpetix

Crown-of-Thorns

16 ratings | 13781 views
Me interacting with crown-of-thorns sea stars. This footage is from Hawaii (the Big Island), where the crown-of-thorns population density is normal and does not present a problem (unlike the "outbreak" situations on the Great Barrier Reef). Where I dive, crown-of-thorns are few and far between, and finding one is always a thrill to me because they are such beautiful and amazing creatures. I love counting the arms (the number varies) or very gently coaxing one up. If you're going to handle a crown-of-thorns, the trick is to be extremely slow, relaxed, and gentle. You have to be careful where (and mostly how) you touch it, and to be aware that at any time you could be pricked, and accept that and be okay with it. They are covered with incredibly sharp venomous thorns that can easily puncture a glove. Some people have very bad (allergic?) reactions to being pricked, but I have been pricked a couple of times (before I got my taming techniques down) with no ill effects other than a little blood and the quick sharp pain, like a spindle. (Being pricked made me SMILE.) Later the spot was tender, swollen/bulgy, and blue just around the puncture location, but it was fine by the next day. However, I don't recommend touching them unless you're aware of the dangers of being pricked, because it's very easy to do it wrong, and it can happen in an instant. If you do pick up a crown-of-thorns and turn it over, the underside is breathtakingly gorgeous. It's one of the most beautiful things I've ever seen. Flower-like, alien, unfurled. A gaping, circular, teeth-lined mouth. Delicate, soft colors, radiatingly symmetrical. Erotic. Fierce. Lovely and voracious like a flower. And all those feet, feet, feet, reaching and exploring, hanging on. The tube feet are huge and yellow, with suckers on the ends, and the crown-of-thorns will hang on to your hand with a powerful grip. Okay, maybe I'm a little crazy, but I AM in love.
Category: Животные
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Text Comments (33)
mmmbad (8 years ago)
Thanks for posting this video. The Crown of Thorns is a very interesting sea creature. I love animals!
lpetix (8 years ago)
Sure! It would be my pleasure. I'm delighted that it helped you out. Wow--COT are such a great topic for a project!
lpetix (9 years ago)
Yep, but not in Hawaii (where this footage is from). I know they have that kind in Thailand.
Judith Distal (9 years ago)
Crown of Thorns are destroying the corals. Due to lack of large fish they overpopulate and can destroy a whole coral reef. Conservation effort are ongoing world wide to kill the Crown of thorns.
lightofgoku (9 years ago)
love the way you see the beauty in these animals, i have to admit since researching them i have become fascinated with the animals that can actually prey on these near invincible starfish especially the triton snail
lpetix (9 years ago)
Its main predator is the Triton's Trumpet, a large snail. Harlequin Shrimp sometimes attack them as well, and fireworms can enter though wounds and feed on them. Pufferfish and Triggerfish can also eat them. (Tough mouths!) Sponges, bivalves, sea squirts, and coral eat crown-of-thorns' larvae.
joebaker1164 (9 years ago)
Dude, thanks for the vid, i learned something today. :D
lpetix (9 years ago)
You're welcome! Thanks for the nice comment! :)
GITart (9 years ago)
This was so cool! Regretfully, I've only seen starfishes dead and dried, and this vid made me feel good, so thanks for making it. Peace
lpetix (9 years ago)
There are differing reasonable philosophies on this. I'm not advocating touching Crown-of-Thorns, but I think it's okay to interact with certain creatures if you're mindful about it. Gently touching a starfish or a curious octopus isn't going to hurt it, and you can learn a lot from the experience. A great resource for divers is Dee Scarr's book "Touch the Sea," which has been very inspirational to me. Check out her website at touchtheseaDOTcom (replace DOT with a dot!)
lpetix (10 years ago)
Yes, that sounds brilliant. (rolls eyes)
lpetix (10 years ago)
For the next six months, the juvenile sea star slowly grows and develops additional arms, while hiding under reef rock and rubble and feeding on algae. After they get big enough, they emerge and begin to travel the reef in search of food. After two years, they've reached about 20 cm and are developed enough to reproduce. So, they don't have to touch each other to reproduce! But I'm pretty sure they can touch each other without getting pricked, anyway. :)
lpetix (10 years ago)
Okay, I found the answer! They gather in groups during the breeding season, and females shed eggs into the water. The eggs are fertilised by sperm simultaneously released from nearby males, and the fertilised eggs float away, developing into a larva. Over a couple of days, the larva metamorphoses into a tiny "early starfish" stage where they only have 5 rounded-off rudimentary arms. It's super cute! And it's incredibly tiny, less than 1 cm.
lpetix (10 years ago)
Thank you for your wonderful comments/questions! I can't explain off the top of my head how they reproduce, so let me look it up and get back to you... It's so great to find someone else who finds them beautiful. :-) I really love them and think they are just amazing creatures, and it makes me sad how most people hate them and villainize them without knowing all the facts.
lpetix (10 years ago)
Crown-of-thorns don't split in two on their own, but they can regenerate injured arms (for example, if one is eaten by a predator or cut off by a human).
lpetix (10 years ago)
Others think it's actually a natural thing for "blooms" to occur every once in a while, and that it has happened at different times over the past 3000 years. I'm reading a book about it, but it doesn't seem like anyone really knows for sure how or why it happens! It's very mysterious...
lpetix (10 years ago)
Scientists have studied what might cause the outbreaks, and have theories, but there doesn't seem to be a consensus on the reason. Many think it's influenced by human factors messing up the balance of ecology--for example, overfishing or pollution drastically reducing their predators (especially the predators of their tiny larval stage).
lpetix (10 years ago)
Just HOW poisonous depends on how an individual reacts to them. I've been pricked a couple of times with no ill affects, but some people can have bad reactions.
lpetix (10 years ago)
Yes, they are, if you get pricked.
Xecnalxes (10 years ago)
Arent those starfish poisonous?
lpetix (10 years ago)
There are a bunch of shots of COTs turned over in this video! :-)
Papa Bear (10 years ago)
Haha, beautifull animal. :) I can't find any videos with a crown-of-thorns turned over. :/
lpetix (10 years ago)
:-) I LOVE your account name!
lpetix (10 years ago)
Yep... it's just that we don't get huge population explosions of cushion stars, so it's not a big deal... as when there's a small number of Crown-of-Thorns, it's just part of the balance of nature.
lpetix (10 years ago)
You're welcome! Thank YOU for the comments/questions!
lpetix (10 years ago)
Yes, they eat the living part of the coral. (Not the hard stony part that's left behind, but the tiny soft creatures that live inside that and secrete the substance to build new coral.) Crowns-of-thorns aren't the only creatures to eat coral polyps, though. Cushion stars do also, for example.
lpetix (10 years ago)
The problem comes when the balanace of nature gets out of whack (like in Australia) and huge "infestations" occur; then the reef gets very damaged and it's difficult for it to recover. Scientists still aren't totally sure why this sometimes happens, but think it may be something man did to upset the normal balance to nature.
lpetix (10 years ago)
No, not at all... scientists even think that limited predation of a normal population of crown-of-thorns (like in these reefs in Hawaii) actually helps the reef because they eat overabundant varieties of coral, which allows rarer types a chance/room to grow.
lpetix (10 years ago)
Like anything else, if you get too many of them that's when you have a problem...
lpetix (10 years ago)
Thanks! Your Triton Trumpet video is fantastic! I love Hawaii and have returned quite a few times, but I only visited Kauai once and didn't do any diving there. I'm reading a book about Crown-of-Thorns right now, and it says Triton's Trumpets don't always finish off the whole COT when they prey on them... sometimes they'll just eat a few arms, and the COT is able to grow them back. Pretty interesting stuff!
lpetix (10 years ago)
Thank you! :-)
Billy Brice (10 years ago)
Put one on your head
lpetix (10 years ago)
Thanks!!

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