A studio for bird study

Tag: falcon

Published in Ambio: Status and trends of circumpolar Peregrine Falcon and Gyrfalcon populations

by Bryce W. Robinson

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Image copyright Ambio 2019

 

I had the privilege of being included in a recent publication on the status and population trends of two Arctic breeding falcons, the Gyrfalcon and Peregrine Falcon. In this paper, we report population trends for 12 sites across the Arctic where monitoring programs have been in effect.

This work conducted by the Arctic Falcon Specialist Group is important since it combines the efforts of biologists worldwide to form an understanding of the status of the worlds Arctic breeding falcons. The take away is that for the most part, both species seem to be stable, and that continued monitoring is important because of their place as focal ecosystem components in the Arctic.

 

Published in the Journal of Raptor Research: Dietary Plasticity in a Specialist Predator, the Gyrfalcon (Falco rusticolus): New Insights into Diet During Brood Rearing

by Bryce W. Robinson

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I’m privileged to once again see a painting of mine don the cover of the Raptor Research Foundation’s quarterly publication, the Journal of Raptor Research. This time, however, is more special since the painting of a Gyrfalcon carrying its prey, an Arctic ground squirrel, corresponds to the feature article authored by myself and Travis Booms, Marc Bechard, and David L. Anderson.

Our publication titled “Dietary Plasticity in a Specialist Predator, the Gyrfalcon (Falco rusticolus): New Insights into Diet During Brood Rearing” details patterns we documented through implementation of nest cameras in 20 Gyrfalcon nests in 2014 and 2015. The largest camera study of nesting Gyrfalcons provided us with many new insights into the biology of this species, some of which we have already published, some that we have not. In this publication, we document a previously undescribed shift in prey use throughout the nestling period, from a diet of mostly Ptarmigan early in the season, to squirrel in the late season. This shift to squirrel is an important consideration on many levels. It highlights the nuances to Gyrfalcon prey use in Alaska, and the potential importance of squirrels in the later season for juvenile success and development. The apparent importance of squirrels also has implications for understanding ecosystem changes and how shifts in prey landscapes may impact Gyrfalcon reproduction. The stage is set to explore further.

Below are a few photos that describe the work that went into producing this publication. These highlight a some of the >750,000 nest camera images we collected from which the diet was quantified, as well as photos of the field work, and the people that made this effort possible. 

You can read our paper in the Journal of Raptor Research here:

https://bioone.org/journals/journal-of-raptor-research/volume-53/issue-2/JRR-15-58/Dietary-Plasticity-in-a-Specialist-Predator-the-Gyrfalcon-Falco-rusticolus/10.3356/JRR-15-58.full

Gyrfalcon nest 1

A female Gyrfalcon feeds nestlings. Image copyright Bryce W. Robinson/The Peregrine Fund.

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A female Gyrfalcon feeds her newly hatched nestling, alongside hatching eggs. Image copyright Bryce W. Robinson/The Peregrine Fund.

Female Gyrfalcon feeds nestlings Arctic ground squirrel

Female Gyrfalcon delivers an Arctic ground squirrel to nestlings. Image copyright Bryce W. Robinson/The Peregrine Fund.

Gyrfalcon nest 2

A female Gyrfalcon stands alongside c. 14 day old nestlings. Image copyright Bryce W. Robinson/ The Peregrine Fund.

Gyrfalcon nest 3

Parental care photo 1. A female (left) broods newly hatched young, reluctant to leave the nest at the male’s (right) arrival. Every Gyrfalcon would occasionally look at the camera, as seen here, but were otherwise unaffected by its presence. Image copyright Bryce W. Robinson/The Peregrine Fund.

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Parental care photo 2. In some cases, males were keen to participate in brooding and feeding young, as is shown here. In even fewer cases, the females were tolerant of this behavior. Image copyright Bryce W. Robinson/The Peregrine Fund.

Bryce and Gyrfalcon nest camera

Bryce W. Robinson sights in a nest camera at a Gyrfalcon nest. Image by Caitlin M. Davis.

Bryce rappelling into Gyrfalcon nest

Bryce W. Robinson rappelling into a Gyrfalcon nest in western Alaska. Image by Neil Paprocki.

Special thanks to the following people that made the field work happen

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John Earthman and Tinsel

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Neil Paprocki

Ellen in Gyrfalcon nest with nestling

Ellen Whittle holding a Gyrfalcon nestling in 2015.

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Mark Jeter and Ellen Whittle against an Alaskan landscape in 2015.

Special thanks to the institutions that made this work possible: Boise State University, Alaska Department of Fish and Game, and The Peregrine Fund

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Prairie Falcon Painting – In Flight

by Bryce W. Robinson

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Prairie Falcon (Falco mexicanus) in flight. 12×16″ Gouache on watercolor board.

 

Gyrfalcon (Falco rusticolus) Plate

by Bryce W. Robinson

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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!

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