The creative study of birds through art, photography, and writing

Rock Sandpiper – Calidris ptilocnemis, From Curiosity Stems Study

by Bryce W. Robinson

ROSA

Here in western Alaska I’ve been able to spend a bit of time pausing from a focus on Gyrfalcons to watch the Rock Sandpiper – Calidris ptilocnemis on its breeding grounds. My fascination with its appearance, behavior, and vocalizations caused me to look into what is known about their populations and distribution, a factor of bird biology that I’m growing evermore interested in studying. My investigation led me to understand that there occur three separate subspecific populations in Alaska, the nominate ptilocnemis of the Pribilofs, the tschuktschorum of the western mainland, and couesi of the Aleutian archipelago. As I am currently conducting research on the Seward Peninsula, I have been experiencing Calidris ptilocnemis tschuktschorum. 

After some further reading, I learned that the nominate ptilocnemis has the most northern wintering region of any North American shorebird. Remarkably, these birds spend their winters in the Cook Inlet of coastal Alaska. How they manage to find enough food and weather the extreme temperatures and conditions is above my current comprehension, but I was able to find some literature on the subject. Apparently, their is no physiological characteristic or attribute that separates ptilocnemis from other Rock Sandpiper subspecies that would give it the edge to winter so much farther north. The other Rocks could physiologically manage a winter in the north as well, but for whatever reason ptilocnemis is the only ssp. to do so. This seems like a peculiarity, and that is precisely why I am so fascinated by their distribution.

There are other Calidris species that are polytypic, and have separate wintering grounds for each subspecific population. Learning about such cases is extremely enlightening and begs for some contemplation on the matter. Perhaps a polytypic species such as the Rock Sandpiper, or the Red Knot will have an edge on anthropogenic induced changes affecting key migratory sites and their ability to survive the great journey. Perhaps the ability to buffer such disruptions is already built into their distribution at the species level. They are certainly better off than a monotypic species that stops over or winters wholly in a small and localized area. If the lower Pacific Coast of North America becomes a dead zone, then perhaps the subspecies couesi and tschuktschorum will be hard hit, but the nominate ptilocnemis may fair well and maintain a presence for the Rock Sandpiper in North America. As we attempt to be aware of our ever increasing impact, it sure would be nice to know that some birds will be able to wear the disruption, even if it is to a minor degree, so we can then put more energy into those more sensitive.

 

Referenced information:

Gill, Robert E., Pavel S. Tomkovich and Brian J. Mccaffery. 2002. Rock Sandpiper (Calidrisptilocnemis), The Birds of North America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology; Retrieved from the Birds of North America Online:http://bna.birds.cornell.edu/bna/species/686

Ruthrauff, D. R., A. Dekinga, R.E. Gill, and T. Piersma. 2013. Identical Metabolic Rate and Thermal Conductance in Rock Sandpiper (Calidris ptilocnemis) Subspecies with Contrasting Nonbreeding Life Histories. The Auk 130 (1) pp. 60-68

Happy International Guillemot Appreciation Day (IGAD)

by Bryce W. Robinson

BLGULast year my friend Frank, a great birder, asked me a simple question, “Did you celebrate International Guillemot Appreciation Day this year?” I told hime no, and that I had no idea what he was even talking about. He explained that July 27th, if I remember correctly, has been designated to recognize the Black Guillemot. Sounded great to me.

I researched the history a bit, and it seems there is some confusion of whether or not IGAD is July or June 27th. This year, I’ll be celebrating the existence of Guillemots on July 27th. I’ll get it sorted out next year and celebrate in line with what was originally designated as the day to recognize the small Alcids.

This year I illustrated the above Black Guillemot. I haven’t been illustrating much this summer on account of my focus on Gyrfalcon field work, but I made it a priority to put this image together in honor of the birds. I also plan to head to my favorite sea watch spot and watch for an hour or so. I should turn up a few Pigeon Guillemots, and who knows, perhaps a Black or two. The bird would be notable here in Western Alaska in summer, but with birding you never know!

Appreciate a Guillemot today. They sure are class act creatures!

BLGU

Gyrfalcon Project Update

by Bryce W. Robinson

Female Gyrfalcon - Falco rusticolus

Here in western Alaska the bulk of the breeding Gyrfalcons are fledging young at the moment. We were able to install all ten cameras in nests this summer, and starting tomorrow will begin taking them out of the finished nests. I’ve been extremely pleased with the quality of the images that these cameras take. I’ll be spending all winter sorting through the photos to identify prey items brought to the nest. This will be a long process, as I should have somewhere around 1.2 million photos to look through. Quite an undertaking, but I’m excited to start the task.

It’s been a tough season to this point, full of challenges and some failures, but I’m happy with the success we’ve had to this point. Getting all ten cameras placed was a goal of mine, and I’m happy to have that success. For my first year, and the first year of the project, it has gone well. Above all it has been nothing short of an education. There are certainly fruits in difficulties, mistakes, and failures. Next year, I’ll have some experience to draw upon to increase the success and further the project goals.

 

 

Alaska Birds are Gathering for Growth

by Bryce W. Robinson

Wilson's Warbler - Cardellina pusilla

In early July, Alaska birds are gathering for growth. I’ve been very focused on Gyrfalcon diet lately, but it too reflects the general trend of the season here. My eyes have been turning to the thickets lately, as the passerine nests have hatched out in large part. In the past week I have rarely found a passerine without a mouthful of assorted small insects.  The feeding frenzy is in full swing as hungry nestlings require massive amounts of food to fuel their rapid growth.

I appreciate the fast change here in the extreme north west of North America. It’s a great dynamic because it forces you to focus on the moment, as everything is fleeting. Soon, the adults will be joined by an abundance of juvenile birds to watch and study. I sure look forward to that!

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