By Dave Smith – Sydenham Field Naturalists
Purple Martin (Progne subis) is the largest species of the swallow family, they weigh 10-55 grams and 18-22 cm long.
They are on the endangered list as are most insectivores due to the decline in insect population.
These birds overwinter in Brazil and migrate back to this area in the spring to nest and raise there young.
There will be scouts that will start to arrive around the first or second week of April.
They will look for housing to nest and breed.
Established colonies will have birds return to the same area year after year.
It is said that the First Nations people used to put up gourds and in the spring the Martins would nest in them and they would act like an alarm system if they became disturbed by something they would fly out of the houses and create noise alerting the people in the village.
Purple martins will only nest in manmade housing in this area, the gourd is one type of housing used today both natural gourds and plastic ones made to look like a natural gourd.
There are several different types of housing that can be used either purchased or home made.
The one thing in common in all houses is they should be white in colour.
Purple martins make there nests out of small twigs, reeds and mud.
They will lay small white eggs on average five eggs but up to seven they will lay one egg per day when they stop laying the babies will hatch approximately 17 days later then the birds will fledge approximately 20 days later.
They will then form roosts in marsh areas before they go south in the fall these roosts can become so large with millions of birds, they can be picked up on weather radar like a cloud.
These birds are insectivores eating all kinds of insects such as dragon flies, butterflies, fish flies, and mosquitos it is a myth their diet consists of mainly mosquitoes they are only a small percentage of their diet.
The parents will feed their young as much as 60 times a day.
Purple martins have a very unique song like a chatter but very soothing to listen to, also they have a very unique flight they seem to flit about almost stopping and starting in mid flight.
It is very entertaining just to sit and watch and listen to them going about their business.
It is very easy to be a purple martin land lord put up a pole and a house or gourds in the spring and keep the sparrows and starlings out.
After the babies have fledged clean, the cavities and it will be ready for next spring.
Sparrows and starlings are both invasive species and are predators for martins they will build nests over top of a martin nest and will kill martin babies or peck holes in the eggs.
If someone was interested in putting up a purple martin house there are plenty of landlords around that are usually more than willing to talk about what it takes and best practices.
There is a large colony on Walpole Island looked after by the Walpole Purple Martin Project that will fledge over 500 birds a year.
There is a smaller colony in Mitchell’s Bay that is looked after by the Mitchells Bay Area Association that has three T14 houses and a unit of 12 gourds.
This colony will fledge over 200 birds a year.
Sydenham Field Naturalists has a T14 house in Crothers Park that is starting to establish and has fledged more than 25 birds last year.
For more details, visit: http://www.sydenhamfieldnaturalists.ca/