Use a tec suit to tame. Put element in your inventory. Tec suit let's you breath underwater and can boost you through the water at high speed to get fish. I used a crossbow to kill sabertooth, then boost quickly to hesperonis to feed.

I killed the hesperonis I did not want to tame as these will kill the fish and make it difficult to find them.

I tamed them on extinction in the snow biome.

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