For a low level you can use an ichy to lead one of these suckers to the shore and then just tranq it from land, just be mindful about any other water tames (or wild creatures) that might interfere. They're pretty slow and their bite isn't too devastating, but when you're swarmed they can prove to be deadly. I would recommend you knock it out in shallow water so you can keep an eye on its torpor without losing too much oxygen, and bring plenty of meat/narcs if you don't have kibble. They make good defenders if you have your tames in an open body of water and as long as you have enough of em

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