The uncommon iridescence of a common Florida blackbird!
Iridescence is an optical phenomenon with noticeable changes in hue depending on the viewing angle and the angle of illumination. Typical examples of this are insect wings, soap bubbles, oily surfaces or the pearly layers of various sea shells. However, some of the most common of birds are graced with a glorious iridescent sheen as they catch the sunlight. Many times when shooting my favourite herons and egrets, I have been distracted by such beauty when a common Florida blackbird would alight nearby and tease me with its shimmering sheen only to dart away. Generally, they are too quick for me but once in awhile one of these hyper busy fellows will reward me with a cool glance before flying off.
Crows, ravens and blackbirds can be easily confused by their first glance similarities. This slender, stately bird is the male Boat-tailed Grackle (Quiscalus major) which lives in the Florida coastal marshes and wetlands. This particular grackle species is a coastal salt mash dweller and is only known to occur inland in the State of Florida. While similar, crows belong to the family Corvidae that includes ravens, jays, and magpies. Grackles belong to the family Icteridae which includes blackbirds, orioles, meadowlarks and bobolinks. Though similar in appearance the crow is larger attaining between 15 and 20 inches in height and a wingspan of 33 to 39 inches. The grackle grows to between 11 and 13 inches tall and has a wingspan of 14 to 18 inches. Crows are completely black with a sheen to their feathers. At a distance, the grackle appears black with the same sheen, but up close it has a dark purple head, brilliant bluish highlights, and bronze coloration to parts of the body varying a bit depending on the species. The eyes are also a give-away as typical grackle eye color is yellow, while the crow’s are black. Although, in Florida and the gulf coast the Boat-tailed grackle has dark eyes. The one pictured here has dark reddish-brown colored eyes, the colorful iridescent sheen typical of its species, and the long, wedged shaped tail!! But, watch for the glorious colors shimmering out of the black and the more slender body with elongated tail and you’ll probably not confuse with the crows.
Audubon was quite taken with the characteristic iridescence of grackles describing the Purple Grackle ( Quiscalus versicolor, Viell) (or Common Crow-Blackbird as it was known then) as he observed them in Louisiana where much to the irritation of farmers they devoured young corn plants.
“No sooner has the cotton or corn planter begun to turn his land into brown furrows, that the Crow-Blackbirds are seen sailing down from the skirts of the woods, alighting in the fields, and following his track along the ridges of newly-turned earth, with an elegant and elevated step, which shews them to be as fearless and free as the air through which they wing their way. The genial rays of sun shine on their silky plumage, and offer to the ploughman’s eye such rich and varying tints, that no painter, however gifted, could ever imitate them. The coppery bronze, which in one light shews its rich gloss, is, by the least motion of the bird, changed in a moment to brilliant and deep azure, and again, in the next light, becomes refulgent sapphire or emerald-green.”
Grackles are considered a nuisance bird by some, but like the very iridescence which defines their species, it depends on your angle of view. Is the humble blackbird just a common marshland sight easily confused with a crow or a beautifully reflective wonder tossing back waves of color like the ocean catching the sun?