Written in a style that bird watchers of any level of expertise can understand and enjoy, Owls By Day And Night provides information on all the owls of the United States and Canada. The great differences in personalities and habits of owls is introduced. Even experts are likely to learn a few facts on the status of the rare species. The text of this authoritative and detailed owl study is a valuable supplement to the more general field guides, for it tells how to find owls, by day or night, and how to identify species once they are spotted. All eighteen species of owls are covered with a life-like color plate. No ornithology reference book collection can be considered complete without the inclusion of Owls By Day And Night! --Midwest Book Review
It seems owls eventually arouse the interest of any serious birder, but because of the nocturnal nature of owls, few birders actively seek these creatures. Owls by Day and Night is designed to assist the amateur birder in finding and identifying owls in the field. Hamilton Tyler uses the first part of this book to not only develop the idea that the owl and its historical relationship with man clearly differentiates it from other birds, but also to distinguish one owl from the next. To aid in this task a series of tables are used to facilitate the physical and vocal identification of the 18 species of North American owls, as well as their distribution.
The usual species description and life history reports further differentiate one species from another. Though many of the species accounts relate directly to observations made in California, they are quite complete without going to the extent of Bent's Life History series. Tyler's obvious love for owls is evident, as is his concern for their conservation; the final chapter discusses man's present effects on specific habitat types necessary for sustaining certain species of owls.
The paintings by Don Phillips are beautiful, but may be too perfect to be useful to the beginner. The beginner may be too involved in the nondistinguishing features vividly portrayed in some of the paintings to see the distinguishing features. Usually the more experienced birder will know what characteristics to look for and thus not rely on the pictures. I think Phillips' excellent black and white drawings and Tyler's identification tables categorizing owl characteristics are far better tools for field identification.
Owls by Day and Night ends with two fascinating appendices: The first lists alternate common names, useful in relating to the proper species in other literature; the second explains the derivation of the scientific names for each species, providing insight into the relationships between species and to characteristics the original investigators noticed when describing the species in question. --Gordon I. Gould, Jr., California Fish and Game, April 1979
For ardent bird watchers [Owls by Day and Night] should be a joy. 'Observing owls,' says the author, 'is a rather special branch of bird study.' But anyone with the perseverance to head into the darkness, flashlight in hand, by following Tyler's suggestions, should be able to locate the owl he or she hears hooting. To be sure, it's a cagey business following hoots because owls are talented ventriloquists. Moonlit nights are best, of course, both for getting a better look and because owls usually call more frequently when the moon is out. It is also recommended to try 'squeaking like a mouse.'
Daytime searching has advantages. Try tapping a tree with woodpecker holes and 'look for the face of an owl in an opening.' Because owls eat fur, feathers and bones of their prey, this indigestible stuff is regurgitated and mounds of furry pellets pile up beneath an owl's roost, a sure sign of owl territory.
The book corrects some long-held beliefs about owls. They may look wise, but the author says 'crows are more acute than owls with respect to reasoning power.' In addition, he says, 'probably all owls have better daytime vision than man has.' And those erect tufts that characterize certain species are not ears. They are just feathers.
The ears of some owls, by the way, are placed asymmetrically, one above and one below the line of sight. This enables them, as they move their heads, to receive maximum loudness in each ear, which helps to locate prey in the dark. Another reason owls are such successful hunters is that their large, soft-feathered wings allow slow and utterly silent flight.
The book's descriptions of the lifestyle of owls range from that of the tiny, mild-mannered elf owl, a daytime hunter living mostly on insects, to the snowy owl with a wingspread of up to 67 inches, and to the fierce great horned owl, found all over the United States and in all but the most northern parts of Canada. Tyler call him the 'lord of forests, marshes, and brushland.'
Throughout the book, Tyler points out how beneficial this predator is in helping maintain a balance of nature and what an aid he is to farmers in reducing rodent populations. Much research is being carried out on loss of owl habitat. The spotted owl, for example, has been considered a threatened species in Oregon since 1975. The Cooperative Wildlife Research Unit of Oregon State University and the Bureau of Land Management in Medford are both studying the problem. --Mimi Bell, Eugene Register-Guard, Sept. 7, 1978