A studio for bird study

Tag: art

September 6, 2015

Swallow-tailed Kite Movements

by Bryce W. Robinson

Swallow-Tailed Kite - Elanoides forficatus. 11 x 17

Swallow-Tailed Kite – Elanoides forficatus. 11 x 17″ prismacolor on bristol.

I illustrated this Swallow-tailed Kite for my friend Russ. He found Arizona’s first state record back in 2012, so understandably the Swallow-tailed is a special bird to him. You can see the accepted record here:

http://abc.azfo.org/ABCVote/_ABCReports_Public_View_list.aspx

It would be so exciting to see an unexpected X soaring high above the desert. Lately, Swallow-tailed Kites have been showing up in some odd places. For whatever reason a few birds have strayed farther north than their normal range. In this past weeks Rare Bird Alert on the ABA Blog, four separate sightings of the species were made in three different states: Illinois, Indiana, and Kansas. Sometimes birds make strange movements in great distances. You never know, you might be at a hawk watch this fall somewhere in the west and see a large X soaring in the sky. Better start scanning…

2 Comments
July 8, 2015

Singing Bluethroat

by Bryce W. Robinson

Singing Bluethroat

Singing Bluethroat – Luscinia svecica. 11 x 17″ prismacolor on bristol. Image copyright Bryce William Robinson.

On every North American birders “must see” list of Alaskan specialties is the Bluethroat – Luscinia svecica. Not only is this a bird with a restricted North American breeding range, it’s aesthetics and behaviors make it one of the holy grails of an Alaskan bird trip.

I’ve spent a fair amount of time in the habitat that the Bluethroat occupies. I’ve heard many singing males, and on occasion I’ve really listened to them. The Bluethroat sings a compilation song, featuring samples taken from sounds in its surroundings. When I’ve listened and put effort into teasing out each component, I’ve heard the iconic “cricket” chirp which interrupts a mash up of American and Pacific Golden-Plover, Golden-crowned Sparrow, Fox Sparrow, American Tree Sparrow, Gray-cheeked Thrush, Arctic Warbler, and many more. It’s a strange challenge, but a lot of fun. The Bluethroat tends to sing in flight, while doing a flutter like display before descending to a perch. However at times I’ve seen a Bluethroat in an intense song bout, perched atop a willow. It’s these times that I’m able to really watch the Bluethroat, while listening to his repertoire.

It’s no wonder why birders fancy this bird. The male has a multicolored throat that stands out in the brown landscape during their pre-breeding displays. As a mimic, their song fits an old world trend which betrays its natural history. The Bluethroat is an old world species, with a breeding distribution which just leaks into North America. For the birder that goes beyond sight and sound, the distribution adds to the allure.

I don’t get to illustrate much while doing field work here in Alaska. Rarely, poor weather and a break in the work will provide me the opportunity to sit down and draw. I’ve had the Bluethroat on my list for a very long time, so I thought I’d seize the rainy days here in western Alaska. Next I’ll be focusing on more Gyrfalcon illustrations.

5 Comments
April 12, 2015

Gyrfalcon T-shirts

by Bryce W. Robinson

2015-04-07 00.00.00

We have Gyrfalcon T-shirts for sale on the ornithologi`art shop until April 20th. Click the photo or follow the shop link for pricing, sizes, and color options. Represent the Gyrfalcon project and get a shirt!

GYRF

Leave a comment
February 22, 2015

Tail Pumping Behavior in the Black Phoebe

by Bryce W. Robinson

Black Phoebe - Sayornis nigricans. 14 x 17" prismacolor on bristol board. Image copyright Bryce W. Robinson

Black Phoebe – Sayornis nigricans. 14 x 17″ prismacolor on bristol board. Image copyright Bryce W. Robinson

The Black Phoebe – Sayornis nigricans in it’s simple suit of black and white, catches the eye of anyone remotely keen on the goings on of the natural world. This phoebe demands attention, even in a guild of flashy desert denizens. In doing so it provides some quality behavior birding that never disappoints.  

One behavior I have noted while watching the bird forage is the methodic tail flick, not uncommon in the family Tyrannidae, but somehow unique in the Black Phoebe. I’ve wondered about the habit, but never sought to satisfy the wonder until now. The illustration above came about in preparation for the coming San Diego Bird Festival that I will be attending. In practice, I decided to couple the illustration with looking into any insights in the literature regarding the tail pumping habits of the Black Phoebe.

In little time I found a paper (Avellis 2011). The study addressed four hypotheses explaining the behavior, the Balance Hypothesis where the phoebe tail pumps to maintain balance atop unstable perches, the Foraging Enhancement Hypothesis where tail pumping increases foraging success, the Signal to Territorial Intruders Hypothesis where the tail pumping signals conspecifics of the birds fitness and establishment on a territory, and the Signal to Predators Hypothesis where the tail pumps exhibit the birds vigilance amidst predators.

The results of the study indicated the following:

Balance Hypothesis – Not supported

Foraging Enhancement Hypothesis – Not supported

Signal to Territorial Intruders Hypothesis – Not supported

Signal to Predators Hypothesis – Supported

The paper reports that the Black Phoebe increased tail pumping rates significantly when a predator was detected either visually or audibly. The suggested purpose of tail pumping then is to advertise the birds awareness to the predators presence. Tail pumping communicates the phoebe’s health, and that it in turn will be a more difficult prey to capture.

So, when asked why the Black Phoebe pumps its tail, I’ll answer that the behavior is to exhibit the birds vigilance, acting as a deterrent for predators looking for the path of least resistance for procuring food. Another day, another bit of knowledge gained.

Referenced Literature:

Avellis, G. F. 2011. Tail Pumping by the Black Phoebe. The Wilson Journal of Ornithology 123:766-771

5 Comments