Purple martins are large, beautiful swallows that migrate to North America each spring to breed. These aerial acrobats put on quite a show, swooping and diving over fields, lakes, and towns. Their fluid, graceful flight captivates people of all ages. Purple martins are wildly popular birds that have entranced people for ages.
What do purple martins look like?
Adult male purple martins have dark bluish-purple feathers that shimmer in the sun. Their throats are white, and they have a distinctive forked tail. Females are slightly smaller and have gray feathers on their head, back, and underparts. Their throats are light gray, and they have a faint purple sheen on their wings and tail.
Purple martins are the largest member of the swallow family in North America. Adults measure 7 to 8 inches long and have a wingspan of 15 to 16 inches. They weigh 1.9 to 2.3 ounces.
Where do purple martins live?
Purple martins are migratory birds that breed in North America and winter in South America. Their breeding range extends from central Canada south to the Gulf Coast. Some key breeding states include Texas, Arkansas, Louisiana, Mississippi, Alabama, and Florida.
Martins migrate thousands of miles between their summer and winter homes. They leave their breeding grounds beginning in late July and migrate to Brazil, Peru, Bolivia, and other South American countries. Martins arrive at their winter sites in November and December.
Purple martins return to North America beginning in January. They arrive at their colony sites from March through May, traveling up to 300 miles per day. The timing of their migration is tied to the emergence of flying insects that martins rely on for food.
Where do purple martins nest?
Purple martins are extremely social birds that nest in colonies. Colonies can contain just a few pairs to over a hundred pairs. Martins nest in cavities, either natural or provided by humans in the form of birdhouses or gourds.
Natural nesting sites include dead trees with woodpecker holes, cactus cavities, cliff swallow nests, and crevices in buildings. Such sites are relatively rare today. So, most martins nest in artificial multi-compartment houses or gourds provided by martin landlords who value and attract the birds.
Martins often return to the same colony site year after year. Females typically lay 3-6 eggs in a nest made of grasses, leaves, mud or sand. Parents work together to incubate the eggs for about 15 days until hatching.
What is the relationship between purple martins and humans?
Purple martins and humans have had a long, mutually beneficial relationship. Native Americans likely provided some of the first artificial nesting sites for martins prior to European settlement.
When Europeans arrived in North America, they noticed the Native Americans’ martin gourds and poles and quickly adopted the practice. Landlords have been putting up martin housing ever since, enjoying their aerial antics and insect-devouring habits.
Many martin enthusiasts invest countless hours building multi-compartmental housing, managing their colonies, and tracking martin arrivals and reproductive success. Martins offer landlords not just natural beauty and entertainment, but also free help controlling pest insects.
Why are purple martins declining?
Purple martin populations have declined significantly in recent decades. The reasons likely include:
- Habitat loss, especially dead trees with cavities for nesting
- Increased competition for nest sites with invasive bird species
- Declining insect prey base from pesticide use
- Severe weather events on migration or breeding grounds
- Predation of adults, eggs, or nestlings
Despite population declines, purple martins remain a beloved and common fixture of summer for people across North America who maintain martin housing. With devoted human landlords providing homes, martins continue to grace our skies each breeding season.
What do purple martins eat?
Purple martins are aerial insectivores, meaning they exclusively eat insects caught during flight. A martin may consume thousands of flying insects per day. Their diet includes:
- Dragonflies
- Damselflies
- Flies
- Midges
- Bees
- Wasps
- Butterflies/moths
- Mayflies
- Beetles
- Ants
- Grasshoppers
- Crickets
Martins hunt insects by flying from perches on housing or dead snags. They fly back and forth over open fields, lakes, or towns, deftly grabbing insects in mid-air. Their large, triangular bills and wide gapes allow them to adeptly catch flying prey.
How do purple martins help humans by eating insects?
Purple martins provide natural insect control by consuming vast quantities of flying insects, including many pests. Martins are especially valued in agricultural areas, where they eat insects that damage crops and annoy livestock.
Researchers have attempted to quantify the impact martins have on insect populations. One older study in Texas estimated a colony of 500 martins consumes 250 million insects during a 5-month breeding season. More recent research confirms martins reduce flying insect numbers.
Some key insects martins help control include:
- Mosquitoes – martins eat many mosquitoes which may reduce the risk of diseases like West Nile virus.
- Flies – house flies, stable flies, and deer flies are among martin prey items.
- Wasps/hornets – martins capture these feared stinging insects. Their painful stings deter most other predators.
- Mayflies – swarms of these insects emerge from waterways, yet martins adroitly snatch them.
So by housing martins, humans gain a valuable ally in the constant battle against pest insects.
What are some interesting facts about purple martins?
- Purple martins have very short legs that they tuck close to their bodies during flight. Their streamlined shape is adapted for aerial hunting.
- These aerial masters fly up to 40 mph while hunting and migrating. They may log 250 to 500 miles in a day of migration.
- Male purple martins arrive at breeding sites about a week before females to claim prime nesting spots. Older males typically get the best compartments.
- Purple martins have complex vocalizations. Researchers have identified at least 13 different vocalizations used for communicating various messages.
- Since martins nest socially in cavities, they are completely dependent on human landlords in most areas to provide suitable artificial housing.
- Unpaired male martins will sometimes kill nestlings in other males’ compartments, likely so the female will stop brooding and mate again.
- Purple martins undergo a complete molt before fall migration. Both adults and juveniles replace every feather from August to October, leaving them with fresh plumage to migrate.
- Banding studies show purple martins can live 13 years or more in the wild. The oldest known martin was at least 15 years old.
How can you attract purple martins?
Here are some tips to attract martins to your location:
- Provide suitable artificial housing – multiple compartment houses or gourds mounted on poles, placed in an open area clear of trees/wires. Place near water with open flyways for foraging.
- Offer the housing early – put it up in February or March before scouts arrive looking for sites.
- Keep competitor birds out – plug holes in the off-season, regularly monitor sites for European starlings and house sparrows and remove nests/deter with exclusion devices as needed.
- Register your site with Purple Martin Conservation Association to get info to attract and care for martins.
- Be patient – it may take a few years for martins to discover and populate the site.
- Educate others – share your passion for martins and importance of conservation to help their populations thrive.
Conclusion
Purple martins are majestic aerialists that offer beauty, natural pest control, and endless entertainment. Their fluid, graceful flight and chortling, gurgling songs never cease to delight martin enthusiasts. With devoted human landlords providing nest sites, we can ensure purple martins continue dancing each summer across the skies of North America.
