I’ve been working on What in the Wild? Secrets of Nature Concealed . . . and Revealed (a sequel to Where in the Wild? and the soon-to-be-released Where Else in the Wild?). One of nature’s secrets to be discussed is the nest holes of kingfishers, those handsome, crested birds of watery places who burrow into the riverbanks to make their nests. How deep? It turns out there is no clear answer to this question, as I discovered in my research, which led to some ruminations that will be the subject of this post.

The authors of Wildlife and Plants, 3rd edition (Marshall Cavendish Reference) write that the nest tunnels are “3-7 feet long.” In Water Birds of California, author Howard L. Cogswell says “3 to 6 feet (even 10),” while World Book Encyclopedia reports “4-15 feet.” So which is it?

Those who read non-fiction often seem to have the impression that facts are facts. Period. The writer of non-fiction must merely learn them and report them, and that’s that. I’ve gotten this attitude often from children, egged on by the adults in their lives. “You wrote X, but we read Y in another book. Who is right and who is wrong?” Cheers for the author of truth. Jeers for the liars. But in reality, the depth of kingfisher tunnels (and many other facts) are unknowable. It might be instructive to consider how the figures above have come to light.

Over 200 or so years of American ornithological research, what percentage of kingfisher nests have been measured? [Read more…]