Ornithologi

A studio for bird study

Tag: raptors

An Illustration of Some Members of the Genus Buteo

by Bryce W. Robinson

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18×24″ Gouache on watercolor paper. From top left: Rough-legged Hawk (Buteo lagopus), Swainson’s Hawk (Buteo swainsoni), Broad-winged Hawk (Buteo platypterus), Red-tailed Hawk (Buteo jamaicensis), Red-shouldered Hawk (Buteo lineatus), and Ferruginous Hawk (Buteo regalis). Purchase limited edition prints here.

I’ve been illustrating raptors in flight for some years now, which really took off when I met Jerry Liguori. Jerry took me under his wing, so to speak, and filled my head with everything he himself has learned over his many years studying the identification of raptors, particularly in flight. His tutelage accelerated my skills and knowledge in raptor identification, and I can confidently say that without his selfless teaching, my illustrations wouldn’t be the same.

I’m currently focused on tuning in my raptors in flight. I am about to start some large illustration projects focused on these taxa, so I am working to develop my technique and process as well perfecting relative shape and sizes. It’s a challenge, because illustrating each correctly involves so much more than the obvious differences in plumage. What makes each unique are shape, proportion, and posture. I’ve found posture to be the most challenging aspect to capture, since this seemingly simple factor has so much power over whether the bird looks real or not. Furthermore, in flight postures and shapes are influenced by the direction and motion of a bird in that moment in time. For instance, a bird soaring has a unique shape but because of the position of the viewer, that shape may be different for each wing because of the birds posture and how wind or resistance bends the outer primaries. To understand and master this effect is going to take repeated sketching and exploration.

Purchase an 18×24″ limited edition archival print (30 available) of this illustration in the shop. Your support helps me continue to refine my illustration, so thank you ahead of time! Also, be sure to add Jerry Liguori’s unique guidebooks to your library. Jerry has taken raptor identification to the next level, and his guidebooks are a wealth of information for mastering in-flight identification. You can find his books here: Jerry Liguori’s Hawk’s From Every Angle and Hawks at a Distance

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Just Published: Applied Raptor Ecology: Essentials from Gyrfalcon Research

by Bryce W. Robinson

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The Peregrine Fund just released a new book, “Applied Raptor Ecology: Essentials from Gyrfalcon Research”. This book serves as a techniques manual geared towards providing early career researchers with information and a stepwise guide for conducting various research on raptors. This information is also supplemented by mock data, and R code to help the researcher begin to form skills in R and analysis.

Although I am the clown in orange on the cover, my true contribution is found inside the book. I contributed as an author of a chapter – Quantifying Diet; an appendix – Guidelines for Conducting a Camera Study of Nesting Raptors; and as coauthor of an appendix – A Photographic and Morphometric Guide to Aging Gyrfalcon Nestlings.

For more information and to purchase the book, go here:

http://science.peregrinefund.org/applied-raptor-ecology

*PDF’s of each chapter will be available January 2018

Notes on Gyrfalcon Molt

by Bryce W. Robinson

Adult Male Gyrfalcon - Falco rusticolus

Photo 1. Adult Male Gyrfalcon – Falco rusticolus

I like to pay attention to molt in birds. There are many aspects of a birds life history that can be reflected by their strategy for feather replacement. A great example is something I’ve been watching with the nesting Gyrfalcons I’ve been working with lately.

Last summer, I noticed something about the molt between male and female Gyrfalcons. While I was entering nests to install cameras in the early nesting period (mostly during incubation), I noticed that males were behind females in their molt progression. Following my initial observation, I started paying closer attention to each bird. I continue to take notes on this, and wanted to share the molt of a pair from a nest I visited recently.

Adult Female Gyrfalcon - Falco rusticolus

Photo 2. Adult Female Gyrfalcon – Falco rusticolus

You can see that the male (photo 1) has just dropped his fifth primary. Falcons generally begin their primary molt at P 4&5 and progress in two directions. The female (photo 2) has dropped her third, fourth, fifth, and sixth primaries. You can see P 4&5 are growing in already.

This illustrates a few simple things in the life of a Gyrfalcon. One, that energetics govern the ability to molt. Two, that male and female Gyrfalcons have different energetic roles and energy budgets during incubation and early brood rearing. They have different roles in the process. These are illustrated by the fact that they differ in the progression of their molt.

Later, the rates even out as both adults need to provision for their growing brood. I hope to get photos of this pair on my next visit to the nest in a few weeks.