Boat-tailed Grackle

Quiscalus major

(c) Charles Bush
  • ICTERIDAE
  • Blackbirds, Orioles, and allies
  • Passeriformes
  • Tordo cola ancha, Zanate pico de bote
  • Quiscale des marais
Introduction
A very large, glossy black bird, the Boat-tailed Grackle's common name refers to its long tail, often held in a V-shape to form a "keel." Found along the coast from Texas to Long Island, this songbird prefers salt and brackish marshes, where it breeds in colonies and socializes in noisy flocks. The Boat-tailed Grackle has been expanding its range northward since the 1940's, probably due to milder winters north of the Carolinas.
Anne Toal, Creative Commons license, CC-BY
Appearance Description
Large, slender birds with substantial bills, Boat-tailed Grackles often hold their long tails in a V-shape. The males are essentially black from bill to tail. Their feathers have a metallic shine, with the crown and neck a glossy blue-black, and the body a glossy greenish-black. The female is a light, warm brown with dark brown wings and tail. The female’s “ear” is darker brown under a pale eyebrow. The eyes of both sexes are yellow. The size of a small crow, the male Boat-tailed Grackle weighs 8 ounces, grows to 16.5 inches, and has a 23-inch wingspan. Females are smaller, weighing 4.2 ounces, and reaching 14.5 inches in length, with a 17.5 inch wingspan.
Range Map
Courtesy Kenn Kaufman
Range Distribution
Boat-tailed Grackles are permanent residents along the Gulf and Atlantic coasts of the United States, from mid-Texas to Virginia. Breeding populations reach Long Island, New York. These grackles also occur across the Florida peninsula.
 
A legend for the range map to the right can be found here.
Habitat
The Boat-tailed Grackle is always close to tidal water, but nests on freshwater marshes, lakes, and impoundments. Groves and tall vegetation are used for breeding and roosting. Like other grackles, this species forages over a variety of habitats: salt or freshwater marshes, mudflats, beaches, farmlands, parks, and open, urban areas.
Feeding
The omnivorous Boat-tailed Grackle’s diet changes with the seasons. Walking methodically, this grackle picks items from the ground and moves leaf litter to find insects, snails, frogs, and cereal grains. Some populations will moisten dry foods. From shallow water, the grackle grabs shrimp, tadpoles, fish, and mussels. The Boat-tailed Grackle will raid other birds’ nests for eggs and young. A variety of human food is scavenged from lawns, dumps, and city streets.
Reproduction
In early spring, female Boat-tailed Grackles scout potential nesting sites and gather in groups that will form colonies in tall grasses, cattails, trees, and shrubs. Males exert control over these “harems” according to hierarchies determined by age. Males or females that are close in rank may fight. Female Boat-tailed Grackles show little fidelity to the older males that guard the harem; low ranking males appear to sire the majority of young.
 
Female Boat-tailed Grackles build a large bowl in stages, usually on a platform of coarse grasses 3 to 15 feet above water or land. They finish it off with fine plant materials pressed into a layer of mud or animal dung. Females raise the young alone from incubation (13 days) through fledging (12-15 days), and during 5 or more weeks of a protracted juvenile period. Juveniles may learn complex feeding and defensive techniques in flocks of females and young. After approximately a year, males move into separate flocks.
Migration
Most Boat-tailed Grackles do not migrate. Northern populations withdraw south of Virginia in the winter, and post-breeding birds in Texas move slightly south along the Gulf Coast.
CBC Graph
Graph Legend
Annual Population Indices
  • 3,700,000
  • 3,700,000
  • population expanding, no current conservation concerns
Population Status Trends
Christmas Bird Count and Breeding Bird Survey data both confirm that the Boat-tailed Grackle has increased significantly and expanded its range northward along the mid-Atlantic, from North Carolina into Long Island. This expansion began in the 1940's, accelerated through the 1950's, and then slowed in the 1970's. Presently, the expansion continues slowly into southern New England and slightly inland.
 
An explanation of the Annual Indices graph displayed to the right can be found here.
Conservation Issues
For some farmers and coastal residents, the success of the Boat-tailed Grackle has resulted in damaged crops and disturbed peace. Outside the breeding season, this conspicuous grackle joins mixed species flocks to forage on cereal grains and gather in large, noisy roosts.
 

The United States Department of Agriculture’s Wildlife Services reports that Boat-tailed Grackles are a minor participant in crop damage, and combines several techniques to remove them from crop lands: harassment, manipulation of water levels in rice fields, removal of cover for roosts, provision of alternative foods, delayed planting, bird-proof barriers, and crop rotation. Chemical repellents are under development. Where damage is severe and frequent, lethal methods include shooting, trapping, suffocation with carbon dioxide, and chemical poisoning.

What You Can Do
Explore the wetland habitats of the Atlantic and Gulf coasts to look for the magnificent Boat-tailed Grackle.
 
For dispersing and relocating Boat-tailed Grackles, support the use of non-lethal techniques that release fewer pesticides into our shared environment.
 

 

Buy produce and cereal foods grown with minimal environmental impact and humane dispersal methods. Pesticides like Avitrol cause pain and suffering in some birds; the entire flock then becomes disturbed enough to leave.
 
For actions you can take, including Audubon activities, please visit our resources page.
More Information
Visit our resources page for more information about this species.
Natural History References
Kaufman, Kenn. Lives of North American Birds. Houghton Mifflin Company, New York, 1996.
 
LeBaron, Geoffrey S. “Range Expansion of Boat-tailed and Great-tailed Grackles.” BirdSource: Birding with a Purpose. The National Audubon Society and Cornell Lab of Ornithology. 2 June 2006.
 
Post, W., J. P. Poston, and G. T. Bancroft. 1996. Boat-tailed Grackle (Quiscalus major). In The Birds of North America, No. 207 (A. Poole and F. Gill, eds.). The Academy of Natural Sciences, Philadelphia, and The American Ornithologists’ Union, Washington, D.C.
 
Sibley, David Allen. 2000. The Sibley Guide to Birds. Alfred A. Knopf, New York.
Conservation Status References
Kaufman, Kenn. 1996. Lives of North American Birds. Houghton Mifflin Company, New York.
 
LeBaron, Geoffrey S. “Range Expansion of Boat-tailed and Great-tailed Grackles.” BirdSource: Birding with a Purpose. The National Audubon Society and Cornell Lab of Ornithology. 2 June 2006.
 
Post, W., J. P. Poston, and G. T. Bancroft. 1996. Boat-tailed Grackle (Quiscalus major). In The Birds of North America, No. 207 (A. Poole and F. Gill, eds.). The Academy of Natural Sciences, Philadelphia, and The American Ornithologists’ Union, Washington, D.C.
 
Sibley, David Allen. 2000. The Sibley Guide to Birds. Alfred A. Knopf, New York.