Hello and welcome to the latest post in the Species Spotlight series. Today, we are going to learn more about the magnificent Purple Martin.

Purple Martin: Birds of a Feather

Purple Martins are the largest swallow species in North America and one of the largest in the world. They are around 7.5 – 7.9 in. long with a wingspan of 15.3-16.1 in. This is between the size of a sparrow and a robin. Other area native swallow species are smaller, like the Tree Swallows at 4.7 – 5.9 in. and wingspan of 11.8 – 13.8 in. and Barn Swallows at 5.9 -7.5 in. long and a wingspan of 11.4 – 12.6 in. All of them have forked tails and tapered wings.

Males are iridescent blue-purple on their head and body, with black-brown wings and tail. Females or juveniles have grey around their neck and chest, with a lighter white belly. They also have a similar silhouette in flight to other swallow species. However, they may fly higher than their cousins.

At Home on the Refuge

Here in the Pacific Northwest, it is not uncommon to see swallows swoop and spin in aerial acrobatics above local wetlands beginning in the Spring. Multiple species often mix together in these areas, eating insects and drinking water in flight. Barn swallows will build mud nests in the corners of human made structures, while tree swallows will build their nests in the natural cavities of trees.

Historically, Purple Martins would share the habit of their tree dwelling relatives. However, they have come to prefer large birdhouses where flocks may gather to nest and roost together. These structures are often multiple stories resulting in a comparison to apartments or condos. Though if houses are not available, they will spend their spring and summer in woodpecker holes or other natural cavities. They also must compete with European Starlings and House Sparrows for the best cavities.

In the Portland area, they arrive at Tualatin River National Wildlife Refuge in mid Spring to nest and will remain for part of the summer. The seasonal trail allows you to view them more closely, but it is important to stick to the trail to give them space as they nest and provide flight school for their fledgelings later in the season.  Eventually, they migrate back to central South America for the remainder of the year, traveling in such large numbers that they are sometimes visible on radar during migration.

HC, Not HOAs

As with many other species, we can make choices that help support their continued survival by encouraging HC or Habitat Conservation. For Purple Martins, offering housing options is a great first step. This could mean providing houses or hollowed out gourds for them to nest in – preferably elevated off the ground. Or preserving snags to help provide essential habitat for multiple animals. Since they are insectivores, Purple Martins (and many other bird species) are negatively affected by the spraying of insecticides which can harm them. They also can be heavily impacted by severe weather, during migration and other seasons, as events can damage roosting sites and decrease insect populations they rely on for food. If insect populations increase before the Purple Martins arrive, adults and hatchlings are less likely to survive as they must compete for food.

For more information, check out Cornell Lab of Ornithology and Purple Martin Conservation Organization

Photos are original, with all rights reserved by Kirsten Croswell