From her first children's book, The Wildlife ABC, author and illustrator Jan Thornhill has championed a love of nature and wildlife to young readers. Her latest, The Tragic Tale of the Great Auk, is no exception — an informative and heartfelt nonfiction picture book about the causes behind the North Atlantic Ocean bird's extinction in 1844.

The book won Canada's biggest children's literary prizes — the 2017 TD Canadian Children's Literature Award — and was a finalist for the Governor General's Literary Award for young people's literature — illustrated books.

In her own words, Thornhill tells CBC Books about the process of making The Tragic Tale of the Great Auk.

"I do the same amount of research that someone would do if they were writing a nonfiction book for adults, but I have to dump enormous amounts of information because I have such a limitation in the number of words I'm allowed to use.

"I start by gathering all my reference sources and then I copy out stuff from books, sea logs and papers online and end up with a document of all the research. For the book I just finished, which is a companion volume to the auk book about the house sparrow, the reference document is about 250 pages long, single-spaced. So then I go through it and pick out what I think the most important bits are. That gets it down to about 50 pages. Then I divide it into what I think each page will be about and start writing. I wish I could research all this interesting stuff all the time. A day I don't learn something interesting is a day lost as far as I'm concerned."

"I had a sarcoma, a tumour, growing in my wrist for about nine years. It was intraneural, so the tumour was growing through a nerve and it was in my right wrist. I'm right-handed and it hurt to draw. It got worse and I ended up not illustrating a book for 15 years, until The Tragic Tale of the Great Auk.

"Because of the surgery, when I hold a pen my wrist locks so I don't have the same flow of movement that I used to have. For this book, I did it all on computer with a tablet and a stylus in a painting program. It's all drawing, but because I don't have the same control, I blew it up on the screen and scribbled really close up. When you put it down to real size, it looks like I had fabulous control, but it's basically a lot of scribbling."

"A lot of the illustrations of adult auks that exist are based on stuffed auks. Once it was understood that they were disappearing, they suddenly became extremely valuable to museums. People started killing the last ones to sell to museums, which was the end of them.

"Canada has one stuffed auk, which we got in 1965. I actually wrote a piece for Sci/Why, a Canadian children's science writer's blog, about the Canadian stuffed auk, which we have at the Royal Ontario Museum. It was stuck under a sink at Vassar for about 50 years, gathering dust. We finally got it for $12,500 in 1965, which is about the equivalent of $100,000 now. There are only 78 stuffed auks in the world.

"One of the problems was that nobody paid any attention to the chicks, so there's absolutely no description anywhere of what the babies looked like. I had to extrapolate from its closest relative, the razorbill, which is what I based the illustration for the chicks on."