If you are looking to draw incredible birds to your yard, Purple Martins provide watchers with a close view of their nesting, breeding, and feeding antics. These birds are considered to be an attractive addition to an area due to their lovely coloring, pleasant songs, and marvelous aerial acrobatics. In this article, we’re diving deeper into the Purple Martin nest: their nesting habits, where they prefer to nest and how to attract them.
According to data from Partners in Flight, Purple Martins currently have a global breeding population of 7 million, with 90% of those birds traveling and breeding in the U.S. Enticing them to your area can be as simple as creating a place conducive to the building of a Purple Martin nest.
Here are some things you need to know about purple martin nesting habits before hosting a colony of these birds.
Identifying Purple Martins
Purple Martins are easily identified by their large size and unique coloring. At eight inches in length with a wingspan of roughly twelve inches, they are considered to be the largest North American swallow species.
They are not purple as their name suggests, but a deep blackish-blue with an iridescent sheen to their feathers. They can appear in shades from bright blue to deep purple and may even appear green in some light.
While adult males are entirely dark, adult females are dark on top with lighter underparts. Sub-adults also have this lighter coloring, with sub-adult males also having dappled patches of solid black feathers on their torso. It can take up to two years for sub-adults to grow their full adult plumage.
Nesting Near Humans
Purple Martins live almost exclusively near humans in cities and towns, especially in the eastern United States where nearly every Purple Martin nest is built in a man-made cavity. This association between man and martin has been in existence for hundreds of years, making them one of the longest human-managed bird species in North America.
In pre-colonial times, Native Americans erected hollowed out gourds attached to wooden poles to attract the birds to their communities. The birds they attracted and the chicks that hatched would eat the destructive insects that threatened the community’s crops.
The Purple Martin is a year-round insectivore that consumes a wide variety of flying insects, including grasshoppers, katydids, beetles, cicadas, wasps, midges, and horse flies. They forage over open areas during the day, often in pairs of one male and one female.
Purple Martins that nest near humans often find larger nesting chambers and fewer predators than in more natural areas, allowing them to lay more eggs and raise more chicks successfully. They tend to come back to the same nesting sites year after year, especially after raising a brood there in the past.
The Nesting Cavity
Purple Martins prefer to nest in large cavities. In cities, they can be found nesting in buildings, dock pilings, traffic lights, and street lamps, but they are also attracted to natural and artificial gourds and birdhouses made of wood or aluminum.
The older male adults arrive from their wintering grounds in South America first, seeking the same nesting cavity as the previous year if it is still available. Their arrival in the spring is staggered across the country, with birds arriving in southern states as early as January and reaching the northern U.S. around April.
Once the nesting cavity has been chosen, the male will defend it from other males while waiting for the females to arrive. These types of fights are common and can be quite brutal as each bird tries to get the best nesting site.
When a female arrives, she will choose her mate mainly based on the nesting site he controls. Females may visit several before choosing a location as the males try to attract them to their selected nesting cavity. The majority of Purple Martins looking for new nests will be the fledglings from the prior year.
Once the nest cavity has been chosen, the female will begin to gather materials for the nest from the natural resources available in the area. As the female enters, the male will sing a few notes to broadcast his location. Building the nest will take up to two weeks and copulation takes place during the nest building stage.
A Purple Martin nest is generally around one to three inches high and is comprised of three layers. The foundation level is made of twigs and mud with some little rocks interspersed throughout. The middle layer is comprised of smaller twigs, straw, needles, and grasses.
The top level of the nest is a layer of green leaves that line the inside of the structure. While the actual function of these leaves is unknown, it has been speculated that they are used to help keep the nest sanitary, control heat or moisture levels, or work as an insecticide. Sometimes, a mud dam is built in the front of the nest.
Egg Laying And Brood Rearing
Purple Martins generally raise a single brood each year. After the green leaves have been added to the nest, egg-laying starts. The female will lay one pure white egg per day on consecutive days, generally in the morning. Up to seven eggs will be laid, with the average clutch having four eggs.
Incubation of the eggs, which lasts about 15 days, is done by the female alone. While the male may sit on the eggs for brief periods of time, only the female has a brood patch to transfer her heat to the eggs. If the male and female both go to find food, the unattended eggs are covered with leaves.
The hatching of the eggs typically occurs over several days. The young are born extremely frail with totally bare pink skin. Both parents feed the young, making frequent trips with intervals as short as 30 seconds. The chicks will stay in the nest for nearly 30 days, with their feathers beginning to grow in between the 12th and 20th day.
The parents will continue to care for the young until they have mastered flying and obtaining their own food. Once they are no longer dependent on their parents, the breeding season is over and the birds begin to head south to their wintering grounds. Some birds head out as early as July while others may not leave until October.
Creating A Purple Martin Colony
Establishing a Purple Martin colony in a particular area is not difficult and the colony will continue returning to the area each year as long as nesting sites are available. The most important element is plenty of housing cavities available to choose from. Gourds and birdhouses hung from wires or atop poles in open areas are highly desirable real estate for these birds.
Because these birds are very vocal, their taped calls can be used to attract residents to newly established nesting areas. Some retailers specializing in bird supplies have tapes of their chirps for sale.
It is important to protect the newly established colony from predators that would attack the birds, their eggs, or their young. Snakes and other predators that may climb the poles can be thwarted with predator guards and netting on the poles. The colony can also collapse due to poor or wet nest conditions or mite infestation, so stay aware of the conditions in the colony.
- Learn more about how to attract purple martin’s to your yard with our guide: How To Attract Purple Martins To Your Yard
- Blue Jays are another common bird that likes to visit the everyday backyard in the United States. You can learn more about their nesting habits here, and perhaps invite some friends to go along with your purple martins (as long as the blue jays don’t get too bossy!)