PURPLE MARTINS ARE NEAT BIRDS
By Douglas H. Domedion (5/17/12)
have seen the big apartment style bird houses on tall poles in
some folks back yards. They are for purple martins which are
our largest swallow, being about 7-8 inches in length with a
wing span of about 16 inches. The males look all black or purple
depending how the light hits them and the females have a dark
back but are light colored around the belly and chest. Immature
birds look like the female but more drab with a yearling male
having a dirty white belly. They have short legs and do not land
to drink or bath but skim the surface of the water in a pond
Photo caption: MALE PURPLE
MARTIN: The color varies from black to purplish-blue, depending
on the lighting.
These birds catch flying insects, their only
food source, in mid-air as they fly. They do not consume high
numbers of mosquitoes as often claimed. Mosquitoes stay in low
damp areas and only come out at night making them unavailable
to the martins.
Another myth about them is that the first birds
returning in the spring are “scouts” that are checking out nesting
sites and then return for the rest of the flocks. In truth these “scouts” are
just the first birds migrating through and the other birds come
when they are ready.
Early permanent birds set about getting familiar
with the area again and may disappear for a few days as they
do this. They are known for just “lounging around” and enjoying
life for a few weeks before nest building and mating takes place.
Martins nest in cavities and prefer to nest in groups and this
is why apartment type bird houses are put up for them. Once the
females start arriving the males start defending as many martin
house compartments as they can, attempting to attract more than
About four to six weeks after the older birds
return the young from the previous year will return and begin
looking for a site to start their nesting cycle. Many times these
are the birds who start new nesting colonies if good ones are
available. The nesting period may last two months because of
the different age classes and arrival times.
The female does most of the nest building with
material such as grasses, pine needles, sticks, mud and green
leaves. Older birds may lay 2 to 7 soft white eggs while younger
birds may only lay 3 or 4. Incubation is about 16 to 18 days
with the female doing most of the incubation. The brooding period
is about 28 to 30 days after which the young will leave the cavity;
a relatively long period for a bird that size.
About three days before the young do fledge
they will be about the same size or even a little bigger than
an adult and can be too heavy to make that first flight successfully.
The parents must realize this and quit feeding them which causes
them to lose some weight and thus enabling them to do good on
those first flights.
The young will practice their flying and landings
but they still will beg food from the parents for about a week
before they actually start following the adults to learn how
to catch those flying insects. After a few weeks of this activity
most of the martins will gather into staging areas readying themselves
for the long migration to South America where they spend the
winter. Many folks who have put up martin houses have had poor
results. Much of this is caused by poor location, failure to
clean the nesting cavities each year and use some method to discourage
or remove starlings or house sparrows.
Unfortunately the purple martin population has
been declining since the early 1980”s in NYS, around 39%. Check
in next week to see the reasons why and what you can do to reverse
this trend. We did it with the Bluebirds, we can do it with the