Tuesday, February 19, 2013

Wingwraith


This afternoon I glanced out the back window and observed this youngster perched on a brushpile I have along our back fence. A few minutes prior to this the yard was filled with a wider variety of bird species than I have observed all winter. Now the diversity was down to two species - this young Cooper's Hawk Sharp-shinned Hawk and whatever bird was ensconced in the tangle of grass and twigs below him. She was determined to dig his prey out of the sticks and pretty much oblivious to me.




First she worked from the top of the brushpile, peering into the maze of sticks.




Then she started working at the side of the pile.





She must have narrowed down where the bird was hiding and he concentrated on this small area for a while. She wasn't able to pull anything out of here and finally appeared to get frustrated and she quickly darted to the top of the brushpile and began jumping up and down and flapping her wings at which point the House Sparrow she had cornered darted into the nearby hedge. The hawk gave pursuit, but the sparrow had the advantage then and easily outmaneuvered the hawk.



She came back to the brushpile and looked around a bit more, but then retreated to the fence along the backyard where she stayed for a short while before darting into the neighborhood, undoubtedly heading towards the nearest bird feeder.


Sunday, February 10, 2013

Early Bird

I was out for a bit yesterday and found this guy singing. I found quite a few other Horned Larks perched and singing too.  Horned Larks are one of our earliest breeding birds in Montana and I would guess that it is the earliest nesting passerine here. Tony Leukering noted the Colorado Breeding Bird Atlas noted fledgling Horned Larks in Colorado as early as April 7th, meaning that the nest was initiated in early March and he suggests that there may be a few pairs that nest even before that.


The earliest I have observed fledged Horned Larks in Montana was May 6th, although this was in Valley County and there are most certainly birds further south in the state around Billings that nest earlier than that. Although probably not quite as early as in Colorado, I would bet that the birds around here might not be too far behind that. The photo below shows the female and that recently fledged chick I observed in May.

Sunday, February 3, 2013

Book Review - The Unfeathered Bird


The Unfeathered Bird
Katrina van Grouw
Published by Princeton University Press (a review copy was provided by Princeton University Press)
Cloth 2013  $49.95  ISBN: 9780691151342
304 pp.  10 x 12 with 385 duotone/color illustrations.
eBook 2013  $49.95  ISBN 9781400844890



Earlier this week I gave another presentation on penguins to a second grade class. One of the first thing I do when I begin my presentation is ask the children "what is a penguin?"
I usually get a rather quick response that a penguin is a bird, but when I ask "why?" I tend to get quite a few different answers before a child answers "feathers?"

I was reminded of this conversation when I began to read van Grouw's wonderful exposé of the bird underneath the feathers. Even though they are very un-birdlike, penguins possess feathers - this distinctly avian feature - as do all other birds.  Feathers are what immediately separate birds from other (extant) life forms. Van Grouw presents us wonderfully rendered and designed illustrations of birds without this most defining feature and does it with a deep knowledge of avian anatomy and behavior.

The Unfeathered Bird is, at it's heart, an illustrated book of birds of the world broken into two parts. The first part provides us with a primer on the generic bird. The second part depicts how the structure and form of various bird families deviate from the basic bird design. This description sounds like a myriad of other books, however van Grouw has produced a book anything but ordinary. Instead of the appearance of the feathered generic bird, she shows us what's under the feathers, skin, and muscle of the generic bird and then shows how skeletal frame and muscular body have evolved in various bird families to support their specialized lifestyles.

But this isn't a book of just bird anatomy either as the author pointedly states in the first sentence of the Introduction. There are no arrows and labels identifying the bones or muscles, no detailed descriptions of  the how the trochlea of the metatarsal bone of the fourth digit possesses an accessory trochlea in piciform, cuculiform, and psittaciform birds, no detailed line drawings of occipital region of the skull, just wonderfully rendered depictions of the bird underneath the feathers and skin.  The depictions of the generic bird start with a sketch of the rather shapeless bird trunk - no head, legs, or wing, just a football shaped mass of muscle wrapped bone. Further illustrations depict the skeletal features and the muscles of the trunk, the head and neck, the hind limbs and the wings and tail of various species to illustrate basic bird anatomy. The section of the wing and tail also often depicts these structures with the covert feathers removed to better convey how the major flight feathers and tail feathers relate to the muscular and skeletal features underneath.
The second section is the heart of this book - works of art depicting the bird at its most basic for various bird families. The illustrations range from full skeletons to small body parts such as tongues and feet, all rendered in a soft, pleasing sketch-like layout. My favorite illustrations are the birds rendered in typical environments doing the things these birds do - a porpoising Gentoo Penguin, a Wilson's Storm Petrel pattering on the surface of the ocean, or a Eurasian Sparrowhawk plucking its Eurasian Collared Dove prey. The twist is that the penguin is depicted without its skin, the storm-petrel is a skeleton pattering on water, and the sparrowhawk is without it's feather covering shown removing the feathers from it's prey (the only fully feathered bird illustrated in the book). There are a number of these types of illustrations and they are so well done, with an obvious deep knowledge of how birds are put together and how birds behave, that I was easily able to see the feathered bird in my mind.

The other twist in this book is the organization of the bird families. Van Grouw chooses to arrange the birds according to the Systema Naturae of Linnaeus which was based on the structural appearance of birds. It  works well given this book is a depiction the structural appearance of birds and it allows the author to discuss convergent evolution in the text and depict the convergent elements in the illustrations.

The associated text is written in a pleasing non-technical voice and conveys information on the behavior, physiology, and taxonomic relationship between various birds depicted in the book. My only quibbles with this book are minor. I wish that there was at least some attempt to provide a scale with the illustrations. Often I was not sure just how an illustration compared with the actual size of the bird or bird part depicted. I also would have liked to see fewer illustrations of fully fleshed out bird feet.  For instance, one whole page is devoted to the depiction of a fully fleshed Gentoo Penguin foot and I would have loved to see at least one depiction of the skeletal elements of the very distinctive penguin foot. She also missed a great chance to discuss the recent revelation of the relationship between falcons and parrots which becomes very believable with the illustrations of their respective skulls.

This is a book that everyone interested in birds should own and in particular, every bird painter, sculptor, and carver should be required to have this book and study it well. Overall the level of detail in the text is well matched with the artwork  resulting in a comprehensive whole that I think meets the authors goal of making this book a well done "convergence of art and science; accessibility and erudition; old and new; - without compromise and without apology."

More information on the book with examples of some of the illustrations which can be purchased as limited edition prints can be found here.