There are passionate birders and then there’s Peter Kaestner, whose devotion has him traveling the globe in pursuit of the ultimate record. Fewer than 20 people have seen more than 9,000 species, and nobody has reached 10,000, though Kaestner is closing in on it. For this episode of our Summer Read series, Ornithologist and writer Jessie Williamson tags along with him on a rollicking South American adventure.

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