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Robot Submarine Poisons Sea Stars To Save Coral Reefs
schwit1 writes: A 30-kilogram robotic yellow submarine is keeping sea stars in check with poison. The sea stars periodically have huge population booms, and a square kilometer of reef can be home to 100,000 of them. They'll kill off the reefs if left unchecked, but humans can only kill a couple sea stars per minute. The task is overwhelming but simple and repetitive, and thus ripe for automation. The COTSBot has "a maximum speed of over two meters per second and an endurance of over six hours. Five thrusters give it the capability of briefly hovering in the water column, giving it time to attack crown of thorns sea stars with an integrated poison injection system. It's completely autonomous, down to the identification and targeting of [sea stars] lurking among coral."
Actually, we did. Rising ocean temps, dredge spoils and the various things that get into the water from agriculture have seen an explosion in the Crown of Thorns Starfish population, enough to be a threat to the Great Barrier Reef, they leave behind forests of dead, bleached coral, which takes hundreds of years to build up.
Allegedly they considered building robots, because the crown-of-thorns' natural enemy, the giant triton were nearly harvested to death, only eat one starfish a week, and only reproduce slowly in their natural environment.
Technology aside, if a 20 kg carnivorous snail isn't cool, I'm not sure what is.
Wonder if anybody has considered coming up with ways to efficiently breed these guys? I think they'd make awesome pets.
... and cause of the world's problems ?! Just out of curiousity, why the boom in sea star population? Does this happen regularly ie. part of a natural cycle? And does the interruption of that cycle have any repercussions?
Question: should humans intervene in natural processes that they do not completely understand.
Their population growth is due to the nutrients in the water mostly caused by agricultural run-offs and dredging. It's not a natural cycle and they didn't start becoming a problem until the 70s.
This is humans solving human problems. The crown of thorns are destroying many acres of reef at a time which have taken hundreds of years to grow. In terms of the impact of stopping them, coral reefs are the single most ecologically diverse places in the world, and a destroyed coral reef is about as ecologically diverse as a sandy ocean floor, which is to say an absolute wasteland. The loss of the coral reefs would be more devastating to ocean life than over-fishing, ocean acidification (well that also kills reefs), and widespread pollution.
We have been performing population control on the Crown Of Thorns starfish for the best part of 30 years now. The only thing new here is that this machine is more efficient then sending teams of SCUBA divers into the water to perform the task.
Lucky us, it's not poison in the conventional sense. The injection is an agar medium that encourages the growth of pathogenic bacteria, in doing so artificially inducing lethal illness which kills the starfish by bacterial consumption, without introducing any harmful toxins into the ocean. I dug up the paper here, it's actually what my first concern was, bioamplification of the toxin from decomposers to higher-order predators. While COTS seem susceptible to the disease, with other nearby healthy ones, left uninjected, sometimes also becoming infected. Bonus points, another species they tested fared well. (They do note further research necessary, though.)