Fun Facts About Purple Martins

Purple Martin

Sun Metron/Flickr/CC by-SA 2.0

Purple martins are beautiful, beloved songbirds, and are highly sought after as backyard birds, particularly in the eastern United States. One of the largest swallows, purple martins have been known to turn backyards into a haven for their flock, nesting in woodpecker holes or birdhouses. Learn more about these picturesque birds, below.

Purple Martin Facts

  • With a height of 7 to 8 inches and a wingspan up to 15 inches, purple martins are the largest swallows in North America— and one of the largest of the world's roughly 90 swallow and martin bird species.
  • Despite their colorful name, these birds are not actually purple. Their plumage is a dark blue-black with a rich, iridescent sheen. Depending on the light and angle they're at, their color may appear to be royal blue, navy blue, deep purple, or even green.
  • Male purple martins are the only North American swallow with a dark belly. This makes in-flight identification of them easier than with many other swallow species. That being said, birders still need to take care not to confuse purple martins with swifts, which may also have dark underparts, though they have a very different flight style and overall body shape.
  • Different ages and genders of purple martins migrate at different times. Typically, older males migrate first, followed by older females and then younger birds. Because of this, older birds typically secure better nesting sites because they arrive on the breeding grounds first.
  • Purple martins are social, colonial birds, especially in eastern populations. Nesting colonies may include hundreds of pairs of birds, and roosting colonies later in the season may have tens of thousands of birds. The largest roosting colony ever found was estimated to have over 700,000 birds at one time.
  • Purple martins have an insectivorous diet, which means they eat primarily flying insects such as moths, gnats, flies, and mosquitoes. They catch most of their prey while in midair and can even drink in midair, flying over a pond, lake, or stream and scooping water into their bills while they're on the move.
  • Purple martins do most of their feeding between 160 and 500 feet high. Because of this height, mosquitoes make up only a small portion of their daily diet, despite the belief that the birds can eat up to 2,000 mosquitoes per day. They probably could consume that many, but mosquitoes are not generally found at a purple martin's feeding height in such large numbers.
  • Purple martin parents may feed their chicks up to 60 times a day, bringing them various insects that are high in protein and other nutrients the young birds require. Both male and female adult purple martins help feed their young chicks.
  • Purple martins are easily impacted by bad weather. During long periods of cold or rain, there may be no insects available for them to feed on, and, as a result, entire bird colonies can die off if the weather does not improve in two or three days' time.
  • A symbiotic relationship between purple martins and humans began centuries ago. Native Americans would hang gourds for the birds to nest in, hoping to attract them to their land in order to help keep insects away from their crops. Today, eastern purple martin colonies are almost 100 percent dependent on human-supplied housing, though western populations still nest in natural cavities such as tree snags or abandoned woodpecker holes.
  • These birds are geographically loyal and will return to the same nesting site year after year if it is still suitable. Adding new houses to colony sites can help birders accommodate growing purple martin families and increase their local bird population.
  • The longest recorded lifespan of a purple martin was over 13 years.
  • Purple martins can reach flight speeds of more than 40 miles per hour. They're also agile in-flight hunters and can engage in complex aerial acrobatics, which they often do while chasing prey.
  • Purple martins are complete neotropical migrants and will travel from North America in the summer to South America in the winter. Their full migration path can take two to three months to complete, as the birds rest and feed along the way.
  • The purple martin’s worst enemies are the European starling and the house sparrow. Both of these bird species are aggressive toward purple martins and may attack or even kill the birds in competition for prime nesting sites. Other enemies of purple martins include snakes, raccoons, hawks, owls, squirrels, and feral cats. Some predators will actively hunt purple martins, while others will invade their nests to kill young birds or destroy their eggs.