Purple Martins are the largest % of the swallow family in North America. They spend the non-breeding season in Brazil then migrate to North America. Martins that migrate east of the Rockies are totally dependent on human supplied housing. Martins are aerial insectivores, they eat only flying insects, which they catch in flight, there diet is divers, including dragonflies, damselflies, mayflies, june bugs, grasshoppers, bees and so much more. Martins are not however, prodigious consumers of mosquitoes, as is often claimed by many people. PMCA did an intensive 7 year diet study and failed to fine a single mosquito among the samples.
Whether you’re new to housing Purple Martins or have tried in the past and it didn’t work out well; these tips will be helpful to you.
Major reasons people fail to attract Martins is that they place their martin housing incorrectly or their site is inappropriate Martin habit to began with. A reason that Martins don’t stay is because predators take over or you get parasites in the nest.
-They need to be 30-100 feet away from human housing but no further because Martins like — human activity to be near them.
-No trees taller than the Martin House within 40ft
-It needs to be 10-20 feet off the ground
-No bushes or shrubs around the pole
-Boat docks make idea location for Martin homes
-Never have them under wires or have wires connected to them from some other source.
-It needs to be white (its ok to have a little colored trim)
-Compartments have to be a minimum of 6”x6” but they prefer 7”x12”
-Compartment height should be 5”-7” this does not count the neck on a gourd
-Entrance hole 1” above floor or ½” from porch
-Hole size 1 ¾ x 2 ½ they recommend 2 1/8
-Landlords need to be able to lower house daily while starting out to evict any unwanted species
-Nest checks weekly once you have a nesting pair (checking nest will not make your Martins abandon)
-Number all the compartments and keep a written record of activity in each one
-Make sure that you mark your pole so you know what height and what position it was in so that as you do nest checks it always goes back up in to the same position and height.
-Predator guard on the pole
Landlords who have had success last year with their Martin homes should open them up around April 1st-15th. Martins (scouts) have already started their migration and have been spotted in lower Indian already. New Landlords should wait till May 1st-15th when the subadults (last years young) start to come up. The subadults don’t have established colonies so they are looking for new places. Vocalization recordings are a great way to attract Martins.
It is crucial to maintain your houses while you are trying to get the colonies started. Daily checks are highly suggested until you get a Martin in each house. Throw out any unwanted species nest that you find. Once you have Martins you can drop your checks down to once a week. The best time to check them is during midafternoon while the youngling have been feed and the males are out searching for food. If you find that there is a parasite in the nest you will need to take the old nest out and put new dry grass trimmings or straw in place of the old nest. Taking good records will help with your next year.
Do not be discouraged if you are unsuccessful at attracting them right away. Nest building for Martins in our area goes all the way in to late June. If you haven’t gotten any always check that you have followed all the steps for housing, habitat and that you don’t have anything else living in the houses.
Information gathered from: Purple Martin Conservation Association
For further information stop in and talk with us or go online to purplemartin.org