Common Grackle

Quiscalus quiscula
Icteridae

Common Grackles by Audubon; #1 threat to corn crops
Male has glossy blue head
Female duller but still glossy
Heavier body and longer tail than Red-winged Blackbird
Usually just a dark silhouette
But in the right light, head becomes Iridescent
Plumage becomes jewel-like with light refracting through prismatic feather barbules
Plague of Common Grackles en route to breeding sites
Male keeping watch as female builds nest among cat-tails
Female completing nest in hollowed trunk; clutch ranges from 1 to 7 eggs
Hatchling blind and sparsely covered with down
Contour feathers of fledgling provide warmth
Compared to parent, fledgling dull brown with short tail
Like a bottomless pit!
Juvenile lackluster overall compared to parents
Northern populations migrate to southeastern U.S. for winter
Joins other blackbirds in winter flocks numbering up to thousands and millions!

Common Grackles are both noisy and conspicuous when they arrive en masse to breed at Salter Grove in early spring.  When not engaged in breeding activities, lone individuals or small groups forage for insects or other invertebrates in vegetation along the Marsh Trail or in the vicinity of the vernal pond, sometimes even wading into water.  

Grakles are particularly noticeable starting in early June when raucous fledgelings demand food from squawking parents.  By August, the park seems a quieter place with only a handful of grackles remaining.  Later in the year, birds that bred further north may pass through the park in small flocks.

The Common Grackle breeds in North America east of the Rockies and north of Mexico.  Its range has expanded westward as forests were cleared by humans to result in more open areas with scattered trees.  The cultivation of grain crops further enriched its omnivorous diet and has contributed to the increase in population number of this blackbird species.