Sing on, sing on, O thrush!

“Across the noisy street I hear him careless throw One warning utterance sweet; Then faint at first, and low, The full notes closer grow; Hark, what a torrent gush! They pour, they overflow-
Sing on, sing on, O thrush!”

— Austin Dobson, Ballad of the Thrush.

Take a walk in the woods, nearly any woods, and you will probably hear the sweet song of a thrush.  We were scanning thrushes this week!  These lovely birds are always around to serenade your hike, but you'll rarely see them.  Well... most of them.  American robins (Turdus migratorius) are the notable exception here.  They REALLY like to make their presence known, and they firmly believe that they are to be both seen and heard.  Robins are, perhaps, one of the most ubiquitous sounds of spring, but most people don't know that we almost lost the species to the ravages of DDT.  They were saved when larger birds like bald eagles gained protected status, and DDT was banned.  So, every time you enjoy a robin's song, be grateful that they're still here!

The veery (Catharus fuscenscens) is more typical of a thrush.  It's coloring is less flashy, aside from the speckled breast, and it's a lot shier. You're more likely to hear a veery than you are to see one.

The hermit thrush (Catharus guttatus) has one of my all-time favorite songs.  It's so wonderfully melodic!

The varied thrush (Ixoreus naevius) is a bit of a monotone.  It makes up for it, though, by having some stunning plumage!

Image credit: Naturelady on Pixabay.

Fish hawk. Wait, what?

Fish hawk.  No, it's not some sort of bizarre hybrid organism from an obscure horror movie, with the head of a fish, and the body, wings, and talons of a hawk.  But, then again, maybe it should be... !  But, no... Last week we scanned the actual fish hawk, also called an osprey, or more appropriately still, Pandion haliaetus.  This is, without exaggeration, one of the coolest birds that will be in my sample, so this might be a slightly longer than average post.  Osprey are large-ish birds, weighing between 1.4 and 2 kilograms (source), but their wings are especially large, with wingspans up to 180 cm (70 inches)!  Their wings are so long that, even with the generous software trial that Nextengine, Inc. have been kind enough to give me, expanding the size of the objects that I can scan, I still have to scan both the upper and lower surfaces in sections.  That means 4 scans per wing, instead of the usual two.  It's slow going, but it'll be worth it in the end.

Photo credit: NASA via Wikipedia Commons.

Osprey are pretty much obligate piscivores, meaning that their diet is almost exclusively fish.  That, in turn, means that they have to catch fish, and they do so in a particularly flamboyant manner.  They soar quietly above the water, watching carefully for their quarry.  When they spot a fish, the hover briefly above the target, rotate over into a dive, and plummet headfirst toward the water.  Just before impact, they project their feet, adorned by impressively-long talons forward, in front of their heads, and tuck their long wings sharply backward. 

Watching this makes you glad you're not a fish!  Then, if they're successful in their hunt, the emerge from the water, meal in hand (or foot... whatever, semantics.)  Carrying a fish through the air, though, can create a tremendous amount of drag, if you don't orient it correctly.  Fortunately for our osprey, they have especially flexible ankles that allow them to rotate the fish from being perpendicular to their body to parallel, creating a nice streamlined shape, and allowing the bird to minimize its effort to get dinner on the table.

Photo credit: Simon Carrasco via Wikimedia Commons.

A regal hawk.

On today's episode of wing scanning, I wrapped up my sample of the summer hawks (Swainson's hawk; Buteo swainsoni), and have moved on to the largest North American Buteo, the ferruginous hawk (Buteo regalis).  This is another Wyoming bird, and it's totally absent from North Carolina.  But, I realized that at the end of this, I will probably have a pretty nice sample of all of the North American Buteos, which could become a fun little publication all on its own, so here we are. 

This captive ferruginous hawk is showing off the white underbelly and red pants that characterize this species.  Photo credit: Dennis Jarvis via Wikipedia Commons.

The ferruginous hawk really is a pretty regal bird.  First off, it's a big bird.  Big females can mass around 2 kg (4 pounds).  That may not sound like much, if you're used to thinking about mammals, but trust me... in the bird world, that's substantial!  Ferruginous hawks come in a couple of color morphs, dark and light.  The light morph is almost completely white on their bellies and underwings, and they have a beautiful mottled rust red back and legs.  The dark morph has a red-brown color over most of its body, but retains a brilliant white trailing edge on the underside of their wings.  This species is largely dependent upon prairie dogs as their primary source of prey, and have been documented using a particularly unusual hunting style.  Some individuals, apparently, will lay on their sides, talons at the ready, next to a prairie dog burrow.  Then, when the unsuspecting prairie dog pops out above ground, the hawk snags it, and that's lunch.

A ferruginous hawk (Buteo regalis) seeking a new perspective.  Sometimes it best not to question royalty.  Photo credit: Tony Hisgett via Wikipedia Commons.

To help clear up some of the backlog, I thought I would also keep on with the Buteo theme, but bring things back to North Carolina.  Red shouldered hawks (Buteo lineatus) are one of the most common birds of prey in this neck of the woods.  They also happen to be rather pretty.  And much, much smaller (around 775 grams, at the large end) than the ferruginous hawk!

Photo credit: David A. Hofmann via flickr.

Summer hawks. Winter hawks.

Today was a pretty slow day for the scanning project.  We wrapped up our sample of broad-winged hawks (Buteo platypterus), and started on Swainson's hawks (Buteo swainsoni).  I don't think it's really necessary to include the broad-wings here, again, but I love Swainson's hawks.  They were the "summer hawks" when I lived in Laramie, replaced by rough-legged hawks (Buteo lagopus) during the winter.  The Swainson's overwinter in South America, and the rough-legs travel far north into Canada during the summer.  Red tailed hawks (Buteo jamaicensis) are year-round residents in Laramie, and absolutely ubiquitous around here in N.C.  And, on another positive note, I have already scanned a bunch of rough-legs and red tails, so with this post, I am working on reducing the backlog of species to post!

Soaring Swainson's hawk (Buteo swainsoni).  The dark bib and dark trailing edges of the wings are the telltale marks of a Swainson's.  Photo credit: Steven Mlodinow via Macauley Library.

The winter hawk, a rough-legged hawk (Buteo lagopus). The dark carpal patches and belly band are their diagnostic features.  Photo credit: Rodney Crice via Macauley Library.

Apparently, this red tailed hawk (Buteo jamaicensis) spotted the camera!  Dark shoulder patches, and of course (sometimes), the brilliant rust-red tail are diagnostic of this species.  Photo credit: Brian Sullivan via Macauley Library.

Harriers and hawks, and a grosbeak for good measure.

This week has seen some pretty cool birds for the wing scanning project.  Until this week, my intrepid volunteers and I have been working through wings from a bunch of small bird species.  But, since the software trial that was generously provided to me by NextEngine, Inc. is about to expire, I thought it best to push on some of the larger wings that require the enhanced field of vision that NextEngine's enhanced Proscan software unlocks.  So, we've been scanning broad-winged hawks and northern harriers.  The scanner also had a visit from a pine grosbeak!

A northern harrier (Circus cyaneus) in flight. You'll usually see this species gliding low over the landscape, swooping and diving over the terrain.  The white band on their butt is the tell-tale feature that you're looking at a harrier.  Photo credit: Rob Zweers via Wikipedia Commons.

Broad-winged hawks (Buteo platypterus) are pretty common around here.  Photo credit: Alejandro Bayer Tamayo via Wikipedia Commons.

A beautiful pine grosbeak (Pinicola enucleator) from the frozen north.  My specimen is from Alaska.  So, not being from North Carolina, and having only one sample means that it's of limited use for my study, but it was too cool of a wing to pass up!  Photo credit: Ron Knight via Wikipedia.

Crossbills!

I started keeping a record on social media of my wing scanning project a few weeks ago, but I decided that I would be better served to generate content for my website.  So, I will begin that today.  I have a pretty big backlog of cool birds that I've already scanned that I want to talk about, so I will endeavor to get caught up while keeping a running log of the birds that cross my scanner.  So, here we go!

Today I scanned wings from an incredibly cool bird. Loxia curvirostra (red crossbill) is a finch whose bill is particularly well, and peculiarly, adapted to their diet: pine nuts. If you know anything about pine nuts, you know that they are typically encased in a tough, prickly, not very tasty fortress (pine cone). Getting at pine nuts is tough work, which is part of why they're so expensive. That is, unless you're a crossbill! Have a look at that beak! The crossed bill allows the birds to thwart the pine cone's defenses, and get to the good stuff inside.

As a side note, one of my M.Sc. committee members, Craig Benkman, has done a ton of really interesting work studying crossbills and their relationship with the trees that they depend on.

https://www.allaboutbirds.org/guide/Red_Crossbill/id
https://scholar.google.com/citations?user=OMc2dbgAAAAJ&hl=en

Photo credit: Elaine R. Wilson, via http://www.naturespicsonline.com/ 

Photo credit: Brian Small, via http://www.audubon.org/field-guide/bird/lawrences-goldfinch

Moving on today, I encountered another stunning little bird, Spinus lawrencei (Lawrence's goldfinch).

https://neotropical.birds.cornell.edu/Species-Account/nb/species/lawgol/overview

Photo credit: Simon Pierre Barrette, https://commons.wikimedia.org/wiki/User:Cephas

I wrapped up the day with a slightly more common, but still lovely species: Spinus pinus (pine siskin). I used to love hearing the siskins all over the place in Laramie. 

https://www.allaboutbirds.org/guide/Pine_Siskin/overview