The Target Performance Hall at Open Book was jammed to capacity Thursday night, and people filed into the overflow room down the hall. But Helen Macdonald, waiting to go on stage, was not nervous. This event at the Loft Literary Center in Minneapolis was her last event of a month-long tour, and she was relaxed and cheerful.

"I used to be very nervous before speaking engagements," she said. But that was because of her academic background, when she gave lectures where the audience was just waiting to take her apart. It took a while for her to realize that readers and admirers of her best-selling book, "H is for Hawk," were of a different mind-set.

"H is for Hawk," newly released in paperback, has had a remarkable run, and Macdonald has been kept extraordinarily busy traveling and speaking. First published in the United Kingdom in 2014, it won the Samuel Johnson Award and the Costa Book of the Year. It was published in 2015 in the United States and was a New York Times best-seller and a finalist for all kinds of awards—the Kirkus Prize, the Carnegie Medal, and others, and on multiple best-of-the-year lists.

The book is about Macdonald's profound grief when her father dies suddenly and unexpectedly ("We hadn't known he was at all sick," she said last night). She plunges into training a goshawk, an all-consuming passion that necessitates withdrawing from the world. The title, she said, comes from alphabet books, books that children read when they are first learning about the world, because she, too, needed to re-learn how to live.

When she was flying Mabel, her goshawk, she sometimes felt like she herself was a hawk, she said. But goshawks catch their prey and begin eating them before they are dead, which Macdonald could not bear. So she would take over, putting the rabbit or the pheasant out of its misery, wringing its neck with her bare hands. And that, she said, was when she felt the most human, perhaps because she was acting out of compassion, a most human of emotions.

Throughout her talk, Macdonald was funny, witty and entertaining, delightfully surprising the audience, who had, perhaps, expected that an academic scientist who wrote a book about grief might give a talk that was over-serious and depressing. Quite the contrary. Her asides and anecdotes brought waves of laughter.

When she was first getting Mabel accustomed to being around humans, Macdonald said, she used to walk around Cambridge with the bird on her fist. "And there was a small boy who used to run past us screaming, 'Harry Potter! Harry Potter!'" she said. "That made me very angry. This is not an owl! What do they teach kids these days, anyway?"