Location is key for attracting Purple Martins. Make sure your martin housing is in a clear area, at least 30-40 feet away from any tall trees. Having active colony sites in the area will increase your chances of attracting. Using attraction techniques such as decoys and playing the Purple Martin Dawnsong will help increase your chances.
If an entire colony site is lost it is most commonly due to some type of predation; either from hawks, owls, snakes or raccoons. Other reasons for a colony site to abandon are competition from non-native species such as House Sparrows or European Starlings and tree encroachment.
There is no set distance apart the martin housing should be. Fifteen feet apart is enough distance that you can easily maneuver between the two systems, although they can also be farther apart.
Purple Martins do not have a directional preference. Although, if you normally have heavy winds and rains coming in from one direction try to face the entrances opposite. You can also have the entrances face the most open area if you have a less than ideal location.
If the martins abandoned eggs or nestlings then predation is the most likely answer. If you have been conducting regular nest checks and the nestlings were old enough to fledge they may have headed directly to a migratory roost.
YES! At any Purple Martin colony there is a chance for a predator attack. Snakes and raccoons can easily climb wood or metal, round or square poles and aerial predators such as hawks and owls are everywhere. Predator guards help protect your martin colony and prevent disturbances to your colony.
Check the PMCA’s Scout-Arrival Map for an up-to-date view on Purple Martin arrivals.
A small amount of parasites are normal in any Purple Martin nest, however the nest can quickly be overrun with mites, fleas, and blowflies. By conducting regular nest checks every 5-7 days, you can spot any blowflies on the nestlings or mites and fleas in the nests or on the outside of the housing. Cleaning out the old nesting material and replacing it with fresh will help remove the majority of parasites. We do not recommend the use of any pesticides in or around martin nests.
Cold, wet weather or drought can make food scarce for martins. Offering supplemental food like crickets or mealworms can help sustain your martins through periods of extreme weather. If your martins are perched outside the housing, try offering crickets by tossing them in the air near the housing. It may take some time for the martins to accept supplemental food.
First, determine the species of bird. If they are a native species such as a bluebird or Tree Swallow, offer alternate housing and keep the entrances of the martin housing closed until they have accepted the new housing. If the species is a non-native House Sparrow or starling they can be removed by either trapping or shooting.
If you are located within the Purple Martin breeding range, the most important factor in attracting Purple Martins is the housing location. Be sure the martin housing is located in an open area with clear flyways. Strive to have your housing at least 30-40 feet away from any tall trees.
If it’s at the beginning of the season martins will sometimes use colony sites as ‘stopovers,’ resting before flying back to the colony site they nested at the previous year. They could also be birds from a nearby colony site. Martins are social creatures, so they will go out visiting other colonies during the day. Even though they may not be interested in nesting at your colony site, it’s still a good sign--there are Purple Martins in your area and the housing is in a good location.
You can put up your martin housing a few weeks before the martins are due to arrive in your area, but keep the entrances closed. This will help deter other native and non-native cavity-nesting birds such as Tree Swallows, bluebirds, House Sparrows and starlings from claiming the housing.
Keep the entrances of the housing closed until the birds begin to arrive back from migration. Study the Purple Martin arrival map to estimate the arrival date of martins in your area. Have your housing up, but with the entrances closed when the adults are due to arrive. Purple Martins exhibit site fidelity, which means that as long as they had a successful breeding season the year before they will return to that same nesting site. If you are trying to attract Purple Martins you can have your housing up, with entrances closed when the adults are due to arrive. But your best chance will be the subadults, or SY (second year) birds. Subadults are the nestlings that fledged last season. The majority of subadults will nest at new colony sites within the same general area as their natal sites. Through our banding studies we’ve discovered that only about 15% of the young return to nest at the same site they fledged from.
Why not both? Purple Martins will use both gourds and housing, and it can remain the preference of the martin landlord. Whichever type of housing, be sure that it meets some basic requirements: larger cavities sizes (approximately 6”x11”), accessible cavities, and the ability to raise and lower the system.
Martins are colonial nesters, so they like to nest alongside other martins. You should have at least 4 cavities when you are starting out, although 6 cavities are more attractive.
There is no set distance apart the martin housing should be. Fifteen feet apart is enough distance that you can easily maneuver between the two systems, although they can also be farther apart.
If you are replacing the house with an identical house (or gourd rack) there shouldn’t be any problem. A drastic change to a completely different style of house (i.e. from a house to a gourd rack) could disrupt the colony site. If possible, leave the old housing alongside the new housing up for one season.
SREH stands for Starling-Resistant Entrance Holes. These are entrances that will help prevent the non-native European Starlings from nesting in Purple Martin housing while still allowing the martins to enter. There are different types of starling-resistant entrances, the most popular are the crescent, Excluder, Modified Excluder, Excluder II, and Conley II.
If your martins are not used to the more restrictive entrances there is a learning curve to the SREHs. Some martins will take to the new entrances right away, others can take several hours or even days to learn the new entrance. You will often see them stick their heads in and out of the cavity, wiggle around, or fly to a different entrance. While the SREH’s are shorter, they are also wider than a regular round entrance. This gives the martins a little more room to spread out their wings and enter. Once the martins have learned how to enter the starling-resistant entrances, they do so much more quickly.
Yes! Not only do regular nest checks help you manage your colony they are also a lot of fun! Nest checks are a great learning tool for both the young and the old. Martins will not abandon their colony site due to a nest check or nest replacement.
Follow the guidelines here. Nest checks should be done during the afternoon hours. Avoid lowering the housing in the early morning or late evening.
We use pine straw (long soft dried needles from a white pine), using a few handfuls in each cavity. You can also use cedar shavings, commonly sold as hamster bedding.
Yes! Predators are everywhere when your colony site is located in a rural or suburban area. Hawks, owls, raccoons and snakes are some of the common predators of Purple Martins and they can be found all throughout the martins range.
With hawks and owls you may see feathers or entire wings below the housing, or doors ripped off. If you discover missing eggs or young a snake could be the culprit. If you find blood and feathers, it may be a raccoon.
Predator guards are the best defense. Baffles, which attach around the pole help prevent snakes and raccoons from climbing the pole. Guards in front of gourds, or cages in front of housing cavities help prevent owls and hawks from reaching inside. Martins will nest in the back of the cavities so larger cavities will help martins to stay out of reach.
It can. The most important thing is to make sure that the housing is protected right away. Once a predator knows where there is a food source they may be back again. If some martins return to the colony site after the attack they may attempt to renest.
Martins can handle cooler temperatures, it’s the lack of food that is the most concerning. Purple Martins are aerial insectivores, so when temperatures are cool or it is rainy from more than three days the martins cannot find enough food.
Supplemental feeding, with crickets, mealworms, or scrambled eggs can help sustain your martins through bad weather. Follow the steps found here.
While Tree Swallows and bluebirds are wonderful native species, they may try to take over your martin housing. You can successfully raise Tree Swallows, bluebirds and Purple Martins at the same colony site, as long as you follow guidelines. Normally Tree Swallows and bluebirds arrive before Purple Martins. Keep your martin housing entrances closed off if you see any native species taking an interest in the housing. Offer alternative housing (a single-unit gourd or bluebird box) 30-50 feet away from the martin housing. Once the swallows or bluebirds have claimed the alternate housing you may open up a few entrances on the martin housing.
Those are Barn Swallows, a member of the swallow family. They do not complete with martins for housing. Barn Swallows are also aerial insectivores so they will help eat insects and add enjoyment to your colony site.
Both House Sparrows and European Starlings are non-native species and are not protected under any migratory laws. The easiest way to control the species are by means of trapping or shooting. You can choose either cavity traps when they are interested in nesting or bait traps during the non-nesting season.