A studio for bird study

Tag: ornithology

Thoughts on the Past, Present, and Future of the Snowy Plover in North America

by Bryce W. Robinson

Snowy Plover - Charadrius nivosus. 11 x 14 " prismacolor on bristol

Snowy Plover – Charadrius nivosus. 11 x 14 ” prismacolor on bristol. Image copyright Bryce W. Robinson 2015

I’m becoming increasingly fascinated with how our changing world may impact the distribution of a given species, either shifting or fragmenting breeding ranges. I have a particular affinity for the family Charadridae , and I’ve found myself paying closer attention to one species in particular, the Snowy Plover – Charadrius nivosus. The Snowy plover occupies a widespread but disjunct breeding range in its western North American population(Figure 1). This range is likely a result of the bird’s need for specific (in turn limited) habitat for breeding.

Figure 1. Range of Snowy Plover - Charadrius nivosus in North and Central America. Image taken from Birds of North America Online (see referenced information)

Figure 1. Range of Snowy Plover – Charadrius nivosus in North and Central America. Image taken from Birds of North America Online (see referenced information)

The Snowy Plover is a species that has faced many challenges with the ever increasing human presence. Throughout the bird’s North American breeding range (Figure 1), human impacts have caused a multitude of threats to its ability to reproduce. These threats include but are not limited to environmental contaminants, an increase in nest predators such as Raccoon, Common Raven, Coyote, and Red Fox, all of which have experienced a human-subsidized boost in population numbers in recent decades, and recreation on beaches causing both disturbance and nest destruction. A great discussion of all factors impacting Snowy Plover populations can be found on the Birds of North America species account under the Conservation and Management section.

Multiple organizations are working with state and federal wildlife authorities to augment the negative impacts humanity and its residuals are having on Snowy Plover populations. These organizations include Point Blue Conservation ScienceFriends of the Dunes, the National Audubon Society, and many others. The effort is impressive and has seen some success. Still, there is a looming threat on the horizon, the impacts of human induced climatic changes.

What the threats of climate change mean for the Snowy Plover in western North America and across the rest of its range in S. America are still to be determined, but I’d like to emphasize the need to determine and augment these threats as they are occurring. I’ve become aware of a population level analysis that is meant to track the distributional patterns of a given species throughout its yearly cycle (Ruegg et al. 2014). The idea is to identify population structures during the major life events of a species through genetic analysis of individuals at each location; breeding, migration, and non-breeding. Understanding where individuals spend each part of the year holds the power of  identifying where negative impacts are occurring that are driving population declines. This is the big idea behind the banding effort, but this technique provides larger sample size and more power for determining population structures. It’s a huge step in the right direction.

My point is, wouldn’t this be a great tool for assessing changes in populations of the Snowy Plover over its disjunct range as the impacts of climate change become more visible and severe? The answer is yes, and we ought to begin the effort…

Referenced Information:

Page, Gary W., Lynne E. Stenzel, G. W. Page, J. S. Warriner, J. C. Warriner and P. W. Paton. 2009. Snowy Plover (Charadrius nivosus), 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/154

Accessed 7 February 2015

Ruegg, K. C., E. C. Anderson, K. L. Paxton, V. Apkenas, S. Lao, R. B. Siegel, D. F. Desante, F. Moore, T. B. Smith. 2014. Mapping migration in a songbird using high-resolution genetic markers. Molecular Ecology 23:5726-5739

Learning New Skills – Preparing Study Skins

by Bryce W. Robinson

From left to right: Sora - Porzana carolina, 2 male Brown-headed Cowbirds - Molothrus ater, 2 female Brown-headed Cowbirds - Molothrus ater

From left to right: Sora – Porzana carolina, 2 male Brown-headed Cowbirds – Molothrus ater, 2 female Brown-headed Cowbirds – Molothrus ater, all drying after preparation.

I’ve embarked on a new adventure in my ornithological education. I am now learning how to prepare study skins for museum collections with the help of my advisor Dr. David Anderson. My personal catalogue number 001 is a female Brown-headed Cowbird – Molothrus ater (farthest right specimen in the photo).

This is a new experience for me, and one that I’ve been looking forward to for a very long time. I’ll be sharing what I learn along the way.

Black Turnstone Feeding Behavior

by Bryce W. Robinson

 

It is a great experience to see behaviors that obviously gave rise to a creature’s name. The Black Turnstone – Arenaria melanocephala is black, and feeds in the most interesting way as its name implies. It frequents rocky shorelines and turns stones to find food. I was lucky enough to find two birds staging along a tidal pool in western Alaska. The birds were living up to their namesake, turning stones vigorously in search of food.

Another aspect of observation that gives me satisfaction is recognizing a behaviors role in shaping morphology. The turnstone has a unique bill shape, adapted to gain leverage and flip stones in an effortless manner. What I’d like to investigate is the difference in muscle morphology in the neck and back between other close relatives that do not engage in this behavior.

“Behavior birding” holds a treasure trove of opportunities to ask questions and learn great lessons that further understanding of the bird world.

 

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.