Purple martins are the largest species of swallow in North America and a favorite among bird enthusiasts in Tennessee. Known for their speed, agility, and aerial acrobatics, martins put on quite an air show. These migratory birds winter in South America but return to Tennessee each spring to nest. Attracting a colony of purple martins to your yard or property can be very rewarding. But it takes a bit of preparation and maintenance to entice these selective birds.
Why attract purple martins?
There are many benefits to attracting purple martins:
- Natural mosquito and insect control – Martins are voracious insect eaters, devouring thousands of flying insects each day. A single purple martin can consume 2,000 mosquitoes per day!
- Entertainment – Martins are exciting to watch as they dive, swoop, and glide through the sky.
- Help with conservation – Purple martin populations have declined over the years as competition for nesting cavities has increased. Providing housing helps support these birds.
- Part of the ecosystem – Martins are an important component of the eastern US ecosystem and food web.
What do purple martins eat?
Purple martins feed exclusively on flying insects, catching them mid-flight. Their diet consists mainly of:
- Dragonflies
- Damselflies
- Flies
- Midges
- Bees
- Wasps
- Butterflies/moths
- Mosquitoes
Martins are aerial insectivores, meaning they catch all their prey while flying. They do not eat food from bird feeders or the ground.
When do purple martins arrive in Tennessee?
In Tennessee, the purple martin migration happens in the spring:
- Early arrivals: Some older males first appear in late February/early March.
- Peak arrival: Most martins return to Tennessee in mid to late March.
- Females and subadults arrive: Throughout April.
- Depart for winter: Around late July/early August.
Check for martins arriving in your area by consulting with local purple martin landlords or your local nature center.
Where do purple martins nest in Tennessee?
Purple martins nest in colonies and are dependent on humans to provide suitable artificial nesting sites. They prefer nesting in:
- Purple martin houses/condos – Multi-compartment aluminum or wood houses placed up on poles.
- Gourds – Multiples gourds hanged up on a gourd rack.
- Martins may also nest in weep holes under bridges or in abandoned woodpecker cavities (limited natural sites).
What is the best purple martin house for Tennessee?
Here are the top things to look for in a high-quality purple martin house in Tennessee:
- Material: Aluminum houses last the longest. Avoid plastic houses.
- Compartments: 12-14 rooms preferred.
- Size: Minimum 6” x 6” (width x height) compartments.
- Wall thickness: Thick, well-insulated walls help prevent overheating.
- Ventilation: Vents under roof overhang help air flow.
- Access: Starling resistant crescent entrance holes only large enough for martins.
- Pole: Use at least a 20’ tall pole with a rotating pole system.
- Guard rails: Prevents martin predation.
Martin house placement:
- Place house in open area with clear flight path around it.
- Locate far from trees/wires (at least 40’-60’ distance).
- Avoid placing near residential areas disturbed by humans.
When to put up a purple martin house in Tennessee?
Put up martin housing in Tennessee between mid-February and early March before the first scouts arrive. Make sure to have housing up by March 1st.
Steps for installing your martin house:
- Have the house ready to go by late February.
- Purchase/make a quality pole system and have it installed.
- Mount your martin house on top of the pole.
- Have the system ready by March at the latest.
The housing must be up and ready before the first martins arrive so they can inspect it.
Should you clean out old martin nests?
It is not necessary to clean out old nests from past years. Martins prefer nesting in compartments with old nests already established:
- Old nests help stabilize and reinforce new nests.
- Nests contain beneficial parasites that help repel harmful flying insects.
- Martins seem to prefer the scent of old nests.
- Recycling old nests is part of the martins’ natural yearly cycle.
You should clean rooms that have fallen nests, wet/damaged nests, or parasite issues. Otherwise let the martins recycle nests.
How to attract martins to a new house?
It can take patience to attract purple martins to use a new house. Useful tips include:
- Use martin decoys on the porches to lure birds.
- Play recordings of martin dawn song to attract them.
- Keep mammalian predators away from the housing.
- Be persistent! It make take a few seasons.
Making the house attractive with a good location, proper height, and clean nest compartments will also help martins find and use the new site.
Do purple martins reuse the same nest?
Purple martins are colonial cavity nesters and will reuse old nests in housing:
- Old nests are repaired and added onto each breeding season.
- Females seek out rooms with old nests already established.
- A room can contain 5+ years of recycled nest material.
- Nest rebuilding starts when the first females arrive.
Reusing old nests helps ensure stability and saves time and energy. Just monitor for any wet or parasite-infested nests needing removal.
What predators target purple martins in Tennessee?
The main purple martin predators in Tennessee include:
- Hawks – Especially larger species like Cooper’s hawks.
- Owls
- Crows
- Raccoons – Major nighttime nest predator.
- Snakes – Rat snakes and corn snakes may take eggs/nestlings.
- Squirrels
- Domestic cats
Mink and weasels may also occasionally predate martins. Guarding against raccoons, snakes, and hawks is especially important.
Methods to deter martin predators
- Install a predator guard below the martin house entrance holes.
- Keep pole system greased/slippery to thwart climbing raccoons.
- Eliminate nearby tree branches and perches for hawks.
- Use reflective tape near the pole to scare hawks.
- Have a tall, stark pole that deters snakes.
- Trap any problematic predators humanely.
What are the biggest threats to purple martins?
The major threats facing purple martins today include:
- Lack of natural cavities – Martins are 100% dependent on humans for housing.
- Declining insect populations – Due to habitat loss and pesticide use.
- Increased competition – With non-native species for nest sites.
- Predators – Like hawks, owls, raccoons, and snakes.
- Extreme weather – Storms, cold snaps, heat waves, and drought.
- Human disturbance – At nesting colonies and migration/wintering grounds.
Providing quality housing, controlling predators, avoiding pesticide use, and supporting conservation efforts can help protect martins.
Do purple martins return to the same house each year?
It depends. Purple martins exhibit nest site fidelity to varying degrees:
- Adult males often return to previous nesting sites.
- Older females frequently return to successful previous sites.
- Younger martins may switch between different sites.
- Severe weather or predation may deter return to a house.
- Houses renovated/moved may not be returned to.
Providing stable, high-quality housing in the same location each year helps encourage nest site fidelity in your purple martins.
Do you need a license to have a purple martin house in Tennessee?
No special license is needed to put up purple martin housing on private property in Tennessee. However, there are some regulations to be aware of:
- Check local zoning laws for any restrictions.
- Make sure the pole/house does not obstruct aircraft flight paths if near an airport.
- In Tennessee,martin landlords must take down houses by Oct 31 each year.
- Report any martin leg band numbers to help research.
- Follow safe practices and maintenance guidelines for martin housing.
Purple martin houses in Tennessee are considered wildlife shelter and require no permit when placed appropriately on your own private property.
How do you maintain purple martin houses?
Regular maintenance is key to keeping your purple martin housing safe and attractive to martins. Important care tasks include:
- Routine monitoring – Check weekly for any issues.
- Nest checks – Inspect compartments periodically for problems.
- Predator guards – Keep guards in good repair.
- Pole system – Keep pole slick and rotating system functional.
- Parasite prevention – Use traps/ treatments if needed.
- Cleanups – Remove old nests, rinse porches, replace damaged rooms.
Take care of regular maintenance during the martin season. Deep cleanings and repairs are best done after martins migrate.
End-of-season tasks
- Take down house by October 31st in Tennessee.
- Deep clean and sanitize all compartments.
- Make any repairs needed to house.
- Store indoors over winter.
What are signs of a healthy purple martin colony?
Indications your purple martin colony is thriving include:
- Houses are almost fully occupied each season.
- Steady increase in pairs and nestlings each year.
- Martins readily return to the site annually.
- Nestlings successfully fledge each season.
- Active dawn song and other vocalizations.
- Adults actively feeding young and defending the house.
- Good martin weight and plumage condition.
Seeing expansion of the colony over seasons with nesting success shows your site offers suitable housing and foraging to support purple martins.
Tips for attracting purple martins to your yard
Here are some top tips to bring purple martins to nest in your backyard:
- Get appropriate housing up before martins arrive in March.
- Place housing where martins prefer – open area with clear flight access.
- Position housing on a tall, sturdy pole system.
- Use decoys and playback of dawn songs to attract martins.
- Keep predators away with guards and pole deterrents.
- Avoid pesticide use which reduces the insects martins rely on.
- Provide open water source like a fountain or pond.
- Put up additional gourds/rooms as the colony grows.
With proper set up and a little patience, you can turn your yard into a popular spot for purple martins to raise the next generation.
Conclusion
Attracting gorgeous purple martins to nest on your property provides free insect control, endless entertainment, and the satisfaction of supporting a threatened songbird. While martins have specific housing requirements, the effort pays off. Follow nest box recommendations, guard against predators, and maintain sites annually. With some dedication to being a purple martin landlord, you can create a safe haven for martins to thrive in Tennessee.