Friday, June 14, 2013

Flocking Flames

The most abundant native North American bird is the enigmatic Agelaius phoeniceus: the Red-winged Blackbird. Often overlooked by birders, this successful icterid (passerine of the Icteridae family which includes blackbirds, meadowlarks, and New World orioles) utilizes both marshy and grassland habitats for nesting and foraging. Their range extends from coast to coast, and the males' incredibly loud, mechanical "konk-la-reee" songs ring from spring to summer each year, recognized by birders and nonbirders alike.

In their binomial nomenclature,  genus "Agelaius" is derived from Greek 'agelaios', or 'belonging to a flock'. During migration, these blackbirds group in breathtaking flocks of millions of birds.
Their species Latin refers to their red colouration.  Red pigment (carotenoids) cannot be synthesized by the birds themselves, but must be ingested through the foods they eat. On males, this red pigment is obvious during their mating displays, when the red and yellow section of upper secondary covert feathers are clearly visible. This bright patch is called an 'epaulet'.

This male was being banded at Navarre Marsh by Black Swamp Bird Observatory.

Seen in Florida in springtime, the yellow part of the epaulet is visible on this male.

This particular male has a more orange tint to his epaulet, and a neat yellow edging to his tertial feathers and a few coverts.

A layer of black scapular feathers cover the epaulet until the male wants to display. This ability to cover the red patch is very important in the blackbird's life, as, when visible, the red triggers aggression and territoriality in other males. When the male wants to appear friendly or nonterritorial, he covers up his epaulets and thus exhibits no aggression. If he couldn't cover the red, he would be perpetually angry and would be chased around all his life!

Black scapular feathers overlay the bright epaulets. 

In flight, you can clearly see the entire epaulet.

When it comes to females, however, it is not so clear. The girls are a complex streaky brown filled with many shades of cream and peach. The intensity of their colour is highly variable between individuals.
The back and wings are darker than their bellies.

Their bellies are streaked and their head is marked with stripes.

As a female ages, she can develop deeper tones to her face and also her own secondary feathers. Too often the beautiful colouration of the female Red-winged Blackbird is passed by in favour of more striking birds, but when one takes the time to notice the plumage of a seasoned Redwing lady, it is wonderfully rewarding. They are brighter than you would think!

The following photographs are of a breeding female in Ohio, seen on her search for food for her fledgling chicks, on June 14 2013. 

Notice the scarlet secondary feathers-- a deeper shade than many expect!

Here you can see her brood patch-- the bald patch of fluid-filled skin that develops on nesting birds to help incubate their eggs and keep babies warm. The fluid helps conduct more heat to the skin and, because it is bare, the skin can pass heat directly to the eggs/ babies.

These incredible birds are all around us, all the time, but rarely do we ever stop to appreciate their complex plumages. The next time you are out birding, please take a moment to watch the Red-winged Blackbirds as they forage and fly! You'd be surprised at how beautiful they become once you take the time to get to know them!

~Peace always,