I already returned it to my library, but I looked it up for you. It's Sea People: The Puzzle of Polynesia by Christina Thompson. Amazon has it for about $14, and I'm sure any major library would have it, too. It really helped me understand the geography of the Pacific islands, as well as who the Polynesian people are.
I’ve been reading an amazing book about Polynesian settlement. You should check it out. It’s fascinating and a really good read. The problem is it’s led to a google earth and Wikipedia binge where I’ve learned about islands formed by a god doing goatse to captain cook to the physics of sailing and now I’m ready to leave my family and buy a sailboat.
https://www.amazon.com/Sea-People-Polynesia-Christina-Thompson/dp/0062060872
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Modern day Polynesia.