Ornithologi

A studio for bird study

Tag: southwest

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

Advertisements

Beatnik Birding: Madera Canyon, AZ

by Bryce W. Robinson

IMG_0012It’s no secret that Madera Canyon, AZ is one hell of a spot. What I didn’t expect was to climb out of the desolation of the desert into a cool and lush sky island, full of wildlife. After becoming a bit desert dreary, I felt refreshed entering the high woodlands in search of some new birds. I decided I’d go as high as I could, and start hiking from there.

I’ve become quite entranced by the myths of Trogons that can be seen in this part of the country. I held high hopes for this journey up the canyon, but I came away empty handed. What I did find were a good number of birds that I were firsts for me. Long story short, it was a really great morning in Madera Canyon. The place didn’t disappoint bird-wise.

Yellow-eyed Junco- Junco phaeonotus

Yellow-eyed Junco- Junco phaeonotus

Of the throngs of birds I was able to find, I only photographed a few. One of my favorite new birds was the Yellow-eyed Junco. I found a few small flocks, acting just as any junco species does, picking around the ground through the understory. They would notice me, flit to a nearby perch, and look around nervously. These juncos sound quite different than their dark eyed relatives, so when I initially heard them, I knew I was in for something new and good.

Arizona Woodpecker- Picoides arizonae

Arizona Woodpecker- Picoides arizonae

I was really focused on one bird in particular. I love woodpeckers, and the Arizona Woodpecker is a specialty of these parts that I couldn’t wait to find. I heard the bird first, tippy tapping its way around a small Ponderosa Pine grove. It didn’t take long to locate the brown bird. I think the hikers that passed me wondered why I was elated by this brown woodpecker. I’m sure some understood, but others gave me quizzical glances. I giggled a bit, there’s nothing wrong with that.

Painted Redstart- Myioborus pictus

Painted Redstart- Myioborus pictus

Another bird to delight both my eyes and my ears was the fire chested Painted Redstart. These birds were all over the riparian areas of the canyon. I really paid attention to their song, and I think I may have it down. Maybe the next time I hear this bird, I will be able to know what I am listening to.

I can say that Madera Canyon was more than I hoped for. On my way out, I stopped by some feeders and saw a brilliant crimson bird that I immediately knew, although I had never seen. Hepatic Tanager! That is what I said aloud, again receiving concerned looks from the general tourists.

I have yet to have any truly in depth and interesting human interactions. I am hoping I meet a like minded birdnerd soon. I’m headed over to the Patagonia-Sonoita Creek area next, where I’m sure I will run into some other nut jobs. I’ll be keeping an eye out for the Elegant Trogon in that area. Hope I find it!