Purple Martins are a species of swallow native to North America. They are the largest member of the swallow family in North America and known for their speed and agility in flight. Purple Martins are highly social birds that nest in colonies. Their preferred nesting sites are human-provided nest boxes or gourds that are grouped together in open areas near open water. Purple Martins migrate long distances, wintering in South America and returning to North America every spring to breed.
Purple Martins, like many bird species, are attracted to certain colors. Understanding what colors attract Purple Martins can help people who want to attract a Purple Martin colony to their property. The color of a nest box or gourd can influence whether Martins choose to take up residence. Knowing the best color to use can increase the chances of enticing Martins to nest.
How Birds Perceive Color
To understand what colors attract Purple Martins, it helps to know a little bit about avian color vision. Birds see color differently than humans do. They have four types of color receptors in their eyes compared to only three in human eyes. Birds can see ultraviolet light, which humans cannot detect. They also have oil droplets in their eyes that filter light. These adaptations allow birds to perceive a wider range of colors than humans. Birds likely see colors as richer and more vivid than we do.
When considering what color might appeal to a bird, it is important to think about color from their visual perspective, not just how the color appears to human eyes. Just because a color might look dull or uninteresting to a person does not mean a bird would not be visually attracted to it. Purple Martins are sensitive to a wide spectrum of color hues.
Purple Martins’ Color Preferences
Research into avian color vision and field observation of Purple Martins provide some insights into colors that appeal to these birds. When given options, Purple Martins tend to be attracted most strongly to white and light-colored nesting cavities. White likely stands out well against the sky and surroundings, making the entrance holes easy to see. Scientific tests of color preference have shown that Purple Martins prefer white and yellow over darker colors like blue, green, and purple.
Purple Martins do not have an innate avoidance of darker colors though. Colony sites where the nest boxes are painted a variety of colors show Purple Martins readily accept darker colored boxes. However, white boxes are usually the first ones chosen. Having some white nesting cavities interspersed with other colors at a site provides visual contrast and attracts the initial interest of Martins.
Best Colors for Attracting Purple Martins
Based on research into Purple Martin preferences, the following are good color choices for nest boxes and gourds:
- White – This is the most strongly preferred color.
- Light gray
- Beige or tan
- Pale yellow
- Light blue
Darker neutral colors like dark gray, brown, and black can be used but are less attractive to the birds. Bright colors that stand out from the surroundings like red, orange, purple, or teal tend to be avoided. They likely appear unnatural to the birds.
Using WHITE PAINT is recommended, but white plastic or PVC housing is also acceptable. Light-colored, weathered wood that is bleached by the sun is another option Purple Martins find attractive. The key factors are light color and high reflectance.
| Recommended Colors | Less Preferred Colors | Avoided Colors |
|---|---|---|
| White | Dark gray | Red |
| Light gray | Brown | Orange |
| Beige | Black | Purple |
| Tan | Bright teal | |
| Pale yellow | ||
| Light blue |
Entrances and Orientation
The color of the nesting cavity is not the only factor that affects Purple Martin preference. The size, shape, and orientation of the entrance hole also influences choice. Purple Martins prefer a circular entrance about 2 inches across. The entrance hole should be located on the east-southeast side of the nesting box whenever possible. This allows sunlight to strike the interior in the morning but provides shade from the hot afternoon sun. Having the entrance hole facing the proper direction is sometimes more important than color for attracting Purple Martins.
When to Provide Nesting Sites
Purple Martins scout for nesting sites during the day upon arriving in an area in early spring. It is important to have nest boxes or gourds up BEFORE the Martins arrive in the region. The ideal time is late winter about 4-6 weeks before the first sightings usually occur locally. This gives the Martins time to inspect potential nesting cavities. Boxes should be up by mid-March at the latest across most of the Purple Martin breeding range. Leaving them up over winter is acceptable as long as the holes allow drainage.
Where to Place Nesting Sites
In addition to color, Purple Martins are attracted to open, elevated sites near water and open flying space. Martins need to be able to access their nests freely without obstructions or predators. Ideal placement is in the open at least 30-60 feet from trees, buildings, and power lines. Near ponds or lakes is preferable if possible. Purple Martins are social so boxes or gourds should be grouped together in sets of 6-12 or more. Clusters of nesting cavities provide social interaction and help deter predators. Mounting poles 10-20 feet high work well to elevate housing.
Maintenance and Modifications
It is important to do annual maintenance on Purple Martin housing. Used nests should be cleaned out after the breeding season ends. Checks for leaks, holes, and pests should be done. Entrance size, orientation, and interior temperature regulation can be adjusted to better meet the birds’ needs. Adding white partitions between compartments, vent holes, ventilation gaps, or light colored shade roofs helps make the housing more attractive to Purple Martins if they are avoiding darker colored boxes.
Conclusion
In summary, Purple Martins are selective about where they nest and prefer white or light-colored nesting cavities. The most attractive colors are white, light gray, beige, tan, pale yellow, and light blue. Placement, orientation, and housing design are also factors Martins evaluate when choosing a nest site. Providing light-colored nest boxes in open, elevated sites before the Martins arrive in spring is the best way to catch their attention and entice them to take up residence. Aiming to meet the birds’ needs and preferences increases the likelihood of attracting a vibrant Purple Martin colony. With some effort to cater to the species’ nesting desires, anyone can experience the fun of hosting these aerial acrobats in their backyard.
