Ornithologi

A studio for bird study

Tag: identification

Differentiating Adult and Juvenile Gyrfalcon (Falco rusticolus)

by Bryce W. Robinson

Gyrfalcon_Plate-01

Given that much of my career has been focused on the world’s largest falcon, the Gyrfalcon, I often get questions about their life history and Identification. A recurring question is the age of individuals that are observed in winter. Most often, folks ask about juvenile vs. adult, so I decided to make available a simple illustration with annotations as a reference for those with these questions.

What I’ve realized is that fleshy parts confuse a lot of people, since an adult should have yellow legs and cere, whereas a juvenile should have blue. However, it takes female birds much longer to change (well into their second year), and the coloration is also influenced by individual quality and hormones. Some adults, particularly females, tend to be quite dull in the winter (compare this with observations of gull legs in winter, e.g. California Gull). Adults that are likely three years or older (given presence of retained feathers in the upper wing, etc.) can have surprisingly dull legs that may appear blue under certain conditions. The key then is to take a step back and focus on the plumage, since in most cases it is quite straight forward.

The illustration above aims to highlight the key points for aging a Gyrfalcon between adult and juvenile. Eventually I’d like to visually describe more micro-aging factors, but for now I think this will be a helpful resource for those more unfamiliar with this species.

Please, feel free to send me feedback and suggestions. Constructive criticism is always welcome.

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Gyrfalcon (Falco rusticolus) Plate

by Bryce W. Robinson

Gyrfalcon_Plate_2017-11-03-online-01

My friend Kenneth, a Gyrfalcon researcher in Norway, is perhaps the most enthusiastically obsessed Gyrfalcon lover I know. I really appreciate his passion for the bird. Next week he is traveling to Salt Lake City for the Raptor Research Foundation’s annual conference. He asked me to paint a Gyrfalcon portrait for him, so I decided to take the opportunity to illustrate some perched birds to populate the plate I’ve been putting together. I going to produce some giclee prints of this plate, but I’m limiting it to 20 prints. If you like this image, and would like to purchase a print, it is available in the shop!

It’s taken me some time to paint birds that I’m pleased with enough to put into plate form. I’m still a bit at odds with these birds, but I think the above image best fits what I’m going for in creating the plate. My next step will be to paint some different postures and explore which best fills the gap in understanding the different positions and appearances that a Gyrfalcon may take on, in varying conditions. Additionally, the plate needs multiple different in flight postures, and some other age and plumage morph descriptions. Progress has been made either way, and I’m excited!

Below is the painting that I did for Kenneth, as it will look to him. I’ll be traveling to Salt Lake City myself, with this painting alongside me. Thanks for the opportunity Kenneth!

GYRF_Perched-online.jpg

 

The Power of Feathers in Determining Shape and Appearance

by Bryce W. Robinson

 

BANS_03

Consider the photo above and the photo below. The differences in shape are rather dramatic, as the photo above looks rather non-typical of a Swallow. These two photos are of the same Bank Swallow – Riparia riparia, taken seconds apart. 

BANS_02

Photographing swallows in flight itself is either a challenge or futile, I haven’t quite decided. But, if you sit long enough and forget about photography for a moment, you become aware of some incredible bird behavior. I sat alongside a tundra pond a few days ago, where two Bank Swallows and one Tree Swallow made rounds picking emerging insects from the water top. The interactions between the two species, and even between the two conspecifics were entertaining, but the real thriller was their interactions with me. Multiple times the birds flew within inches of my face, all the while giving me close looks at swallow feeding strategy and behavior.

Occasionally, the birds would perch to rest. A few times they choose perches only feet from me. When they landed, the would preen and chatter. One interesting observation during these resting periods was their change in appearance when they roused, or fluffed their feathers. The birds would lose the sleek swallow shape altogether, and in some postures appear more flycatcher-like than a swallow. This made me ponder the power of feathers, as they govern a birds appearance. It’s a bit bizarre, and a useful thing to consider when looking at a far bird, or a photograph that doesn’t quite make sense. Shape is one of the most useful factors in bird identification, but can at times be misleading without extended observation.

A minor complexity in the world of birds, but nonetheless fascinating.

New HawkWatch International Shirts, Featuring My Artwork

by Bryce W. Robinson

HWI new shirts

HawkWatch International recently released a few shirt designs featuring artwork of mine. My friend Mike Shaw had the great idea for a design that took a field guide type format, and put it on the shirt. The shirts feature two Buteos, the Red-tailed Hawk- Buteo jamaicensis, and the Rough-legged Hawk- Buteo lagopus. These illustrations feature callouts that give the viewer a few key tips at identifying the bird. I love the idea, and the shirts turned out great.

A little background on the development of one shirt, the Red-tailed Hawk, might be interesting to some. I really love this illustration for its purity. While counting the raptor migration last fall on the Goshutes Raptor Migration Site in eastern Nevada, I had plenty of time in the evenings to sit by candle light and draw some of the things I saw that day. This illustration was done at nine thousand feet, on the top of a mountain, in the middle of the magic of migration, by candle light. It makes it more special to me, and I hope those that now know where that illustration was born, might enjoy it all the more. I love things with a story attached.

Here are a few images of the illustration on the mountain:

The inception of the illustration

The inception of the illustration

The result, with a splash of the candle light that helped create the image

The result, with a splash of the candle light that helped create the image

If you would like to check out the shirts, or would like to buy any HawkWatch International merchandise follow the link below:

New Shirt Designs Featuring the Art of B William Robinson

HawkWatch International is an incredible organization. I encourage you to support them by purchasing one of their new items. To be transparent, I do not benefit financially from the sales of these shirts. I simply want to see more people joining conservation initiatives. It would be neat to meet someone on the road that I didn’t know from Adam, garnished in one of these shirts, supporting and spreading the good will of conservation, and of course the knowledge and fun of raptor ID.