How would you like to dramatically decrease the mosquito and insect population flying about your yard? You could erect a bat house (not popular with those who believe the critters’ll end up in your hair), or…you could try to attract the insect-voracious purple martin to your home. The purple martin is the largest North American swallow. The family is HIRUNDINIDAE and the species is Progne subis. They lay 3-8 plain white eggs to a clutch, each about 2.4 cm long. The handsome male is uniformly blue/black above and below with a forked tail; the female is similar but light-bellied. Martins resemble the barn swallow but are a few centimeters longer, and stockier in appearance.
Canada’s First Peoples knew benefits The early Native Canadians realized the martins’ appetite for insects. Around their villages they would place hollow gourds as invitations for the birds to nest. It apparently worked well, both for the martins and for the natives, who had fewer insects to pester them. Last summer a fellow gardener had supplied me with a packet of mystery seeds. All I knew is that they were some hybrid of squash. They turned out to be swan gourds (named for the long swan-like neck attached to a pear-shaped body). I allowed one to dry over the winter and hollowed out the contents in early spring. So far there have been no martin residents in my natural birdhouse. Maybe next year.
Choosy about lodgings Hundreds of pairs of martins have been known to nest together. A preferred style of housing is the bird apartment house, or condo. It is recommended to install the condo 40-60 feet from any taller trees. This will deter predators like hawks, owls, snakes and raccoons from attacking the martins or their young. Painting the house white will help to reflect the sun’s heat. Landing shelves should be very narrow to discourage other birds. It seems that purple martins love to be near humans so don’t install your condo further than 60 feet from your home. Any water feature is welcomed as the martins like to swoop down to dip their bills for a cool drink.
Starlings and sparrows are a problem As if natural predators aren’t enough trouble for the purple martin, there are two non-native enemies which were introduced from England in the late 1800s. One is the European starling and the other is the house sparrow. If either species arrives in spring at the condo ahead of the martins, they will take over the structure. If a martin pair finds a vacant apartment, the starling is likely to enter while the martin is out and destroy the eggs or nestlings. Similarly, the house sparrow is likely to enter and poke holes in all the eggs; the objective being to reduce the purple martin population. Unfortunately, they have been successful. To discourage the invaders, condo holes can be plugged with styrofoam coffee cups attached to strings until the purple martins’ spring arrival has been observed. Then they can be popped out and the condo can be home to its rightful owners.
For more information about purple martins and how to attract them, see www.purplemartin.org