Common Grackle

Quiscalus quiscula

Common Grackles are seen daily by most Missourians. They apparently benefit from close association with humans and they are common in suburbs, towns, parks and agrarian landscapes. Gregarious, noisy and numerous, grackles are easily detected because of their tendency to forage in open situations such as lawns and shorelines. They nest in small, loose colonies in overgrown fence rows, damp thickets, farm groves and residential trees and shrubs. They frequently select conifers (Peterjohn and Rice 1991) or other dense foliage to conceal their nests.

Code Frequency

Because Common Grackles are widespread, associate with human-altered habitats and are easy to detect, they would be expected to be recorded in most blocks. Although nests are well concealed, other evidence of breeding was observed frequently due to the abundant, conspicuous nature of the species. Common Grackles were easy for Atlasers to confirm in most blocks by observations of food being delivered to young or young out of the nest. Atlasers who were unable to locate nest sites or other breeding confirmations may have been misled by wandering, foraging flocks or post-breeding individuals.

Distribution

Atlas Project findings indicate that Common Grackles range throughout the state. The species may have nested less frequently in the most-forested portions of the Ozarks, or perhaps it was simply more difficult to confirm there. Robbins and Easterla (1992) suggest that the species has increased in the Ozarks since Widmann's day. Fewer confirmations in north central, central and extreme northwestern Missouri are difficult to explain. Fewer observations in some areas might be attributed to fewer foraging opportunities which force birds to travel greater distances, making them more likely to be missed by Atlasers.

Average Number of Birds / 100 stops

Abundance

Although fewer confirmations were recorded in northern Missouri, this region exhibited the greatest abundance during the Atlas Project. Areas of abundance were highly variable among the natural divisions and produced no definite pattern. Robbins and Easterla (1992) reported that the Mississippi Lowlands had more than twice as many Common Grackles as the Ozark and Glaciated Plains natural divisions based on Breeding Bird Survey data from 1967 through 1989.

Phenology

A total of 627 confirmed breeding reports provide a complete portrayal of Common Grackle breeding phenology. Migration into Missouri commences in late February and peaks in late March to early April (Robbins and Easterla 1992). Breeding is apparently initiated soon after arrival. Because Harrison (1975) stated that Common Grackles produce only one brood, late dates for nest building may represent renesting attempts.

Breeding Evidence

Reported in 1,123 (93.0%) of 1,207 blocks

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