(Cross-posted from The Nature of Things.)
Rare Birds of North America by Steve N.G. Howell
My rating: 4 of 5 stars
Readers might at first be misled by the title of this book. Rare Birds of North America is not, in fact, about the endangered and rare species of endemic birds of this continent. Rather, it is a comprehensive illustrated guide to the birds that don't belong here but manage to find their way here anyway.
These are the birds that are referred to as vagrants. They are native to some other part of the world - East Asia, Western Eurasia, Africa, the Southern Hemisphere, islands - but, for some reason, they have turned up on this continent.
The book explains how and why these vagrants arrive here.
The "how" is simple enough. Birds have wings and they tend to use them to fly to different places. Though they generally follow fairly well-defined routes in migration and in their wanderings about the planet, sometimes when they are in flight something might happen to steer them in a different direction. Most often this is probably related to weather, but other factors may play a role as well, and the authors explore some of the means of dispersal of species.
But why do birds end up in places where they shouldn't be? Again, this is probably most often related to weather conditions, but sometimes birds might simply overshoot their mark. Or, as the population of a particular species increases in one place, they may begin to expand their range and disperse into other areas. This is how many Central and South American species have come to find their way into the states along the southern U.S. border and some have moved even farther north. There is also the possibility that disorientation or misorientation might play a role in the dispersal of species to new areas.
However the vagrants manage to find their way here, when a birder spots one of them and gets the word out, other birders race to the scene, eager to add that bird to their life list. We love watching and documenting the everyday and familiar birds of our region, but the possibility of seeing something exotic from a whole different part of the world is an opportunity that no self-respecting birder would care to miss. And now we have an illustrated guide to help us identify and learn more about these unexpected visitors.
The authors define rare vagrants as those which have had five or fewer individuals reported annually in North America since about 1950. They include species accounts of 262 such birds. These accounts give identification field marks and also discuss the patterns of vagrancy and where the bird might be most likely to be found. The text is accompanied by 275 informative color plates by Ian Lewington.
The book includes helpful appendices which provide a list of birds that are new to North America from 1950 to 2011 and also explanations of why some birds that have hypothetically occurred on the continent are not included in this book.
Overall, I think this book should be a valuable resource for any birder interested in the "birds that shouldn't be here but are." And that, I believe, includes most birders.
(Note: A free copy of this book was provided to me by the publisher in return for an honest review of it. The opinions expressed here are entirely my own. )