The Common Grackle (Quiscalus quiscula) is just that, 'common'. However, it wasn't always common. It was quite scarce in the early 1800s. By the late 1800s it became more common. Jeffries reported it was 'not uncommon' at Grand Falls in 1879. By 1920 it became very common and perhaps was more common then than today. Numbers have decreased significantly in the last 30 years.
The range of the Common Grackle is wide spread. It breeds from western Newfoundland across the Prairie Provinces to inland British Columbia southward to New Mexico and eastward to Florida, a large part of North America. Flocks arrive here in New Brunswick in late March or early April and leave in October prior to gathering into large flocks. Some of the flocks have been epic in size. A flock of 10,000 was reported from Sackville in 1968.
The Common Grackle is one of three grackles which inhabit North America. The Great-tailed Grackle and the Boat-tailed Grackle are much larger than the Common Grackle; 46 cm/18 inches, 42 cm/16.5 inches respectively compared to 32 cm/12.6 inches of the Common Grackle. The Great-tailed Grackle inhabits the southwestern US and Mexico and the Boat-tailed Grackle inhabits the coastal US from Massachusetts to Texas including all of Florida. With the differences in size and geographical location one is not likely to mistake the Common Grackle for its 'cousins'.
The Common Grackle is one of our three common 'blackbirds' which spend their summers here. It is easily differentiated from the Red-winged Blackbird and the Brown-headed Cowbird. It is larger and has no wingbars and is black throughout. On seeing a flock of blackbirds, the Grackles appear larger and heavier in body with a longer tail and a thicker, larger bill. The tail is long and keel-shaped. The tail shape is easily seen in the birds in flight. Grackles are beautiful when the sun shines on them. They show blue, green and bronze iridescence. In a flock this is very beautiful. Grackles have a pale yellow iris. They are noisy birds and can make their presence known. They readily enjoy seed scattered on the ground under your feeders and are not afraid to hop on the feeder or try to get suet from your wire baskets.
Common Grackles prefer open and edge habitats, urban and agricultural areas, marshes, swamps, golf courses, etc. You can see why they are common. They have been able to adapt to many different habitats. The nest is built in a tree, often a conifer, 1 to 3 metres above ground. It is bulky and made of twigs, grass, mud, feathers and sometimes items of human garbage. The 4 to 7 eggs are green to light brown with purple markings and are incubated for 12 to 14 days by the female. The diet of this species includes insects, eggs and nestlings of other bird species, lizards, fish, fruit and seeds. At your feeder they readily eat cracked corn, suet, millet, nuts and sunflower seeds. Indeed, they are a versatile species.
This species is very vocal. Their call is a 'chuck' and their song is a squeaky 'reedle-eak'. This spring we had large flocks of grackles visit our yard. We often saw groups of 10 to 40 or 50. The other birds get upset when the Grackles are around. This is probably due to their preying on the other birds' young or eggs. They also dominate the feeding area and sometimes leave little for the other birds.
In the fall here it is fun to see the Common Grackles gathering in large flocks prior to migration. Birders often check these flocks carefully for other species, especially Rusty Blackbirds. This much less common species shows rusty markings at that time of year and can be easily identified.
Common Grackles are interesting in their being so adaptable. As many of us have seen, some inhabit coastal areas and they have learned to forage along the tide line where they find invertebrates. They will even wade into the water to catch fish. Another interesting behaviour is 'anting'. They will spread out their wings while lying breast-down on the ground and allow ants to crawl through their feathers. It is thought that the formic acid secreted by the ants is used by the Grackle to kill parasites. It has also been observed that single Grackles (who for some reason do not have mates that season) will become helpers to other couples with their offspring.
The Common Grackle, a common species here which flocks with other blackbirds, is an interesting and unique species when one takes a closer look!
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