Every day, I get all kinds of questions about gourds.
"Where do I get them?" "How do I dry them?" "How do I prepare them
for martins?" But, probably the most asked question I receive about
"Why gourds and why do I
say they should be 10" in diameter for Purple
Well, rather than answer each and every
one any more, I'm going to answer it here, and the following is my
Gourds have been around for thousands of years.
Gourds have also been used as housing for purple martins for
thousands of years. And they still make great bird houses today. In
fact, if the time is taken to properly prepare a good sized gourd
for a bird house, it will literally last for years. It is not
uncommon for gourds to last up to 30 years if properly cared
First let's look at why I believe that gourds should be
at least 10" in diameter.
Let's stop and analyze our
situation. If we look at the bird we are trying to attract, AKA, The
Purple Martin, we see it's a member of the Swallow family. But, it's
not just any member of the Swallow family, it happens to be the
'largest' member of the Swallow family, averaging 8" long when an
adult. Now to house one bird, I need a volume of 2" x 2" x 8". OK,
let's carry our analysis a little further. We don't usually only
have one bird in a nest, there are usually 2. A male and a female.
OK, now my volume is at 4" x 2" x 8". But, let's go a little
further. The whole reason for supplying nesting for the martins is
so they will raise young. Therefore; they will need even more room.
A pair of martins can lay as many as 7 eggs. So how much room can 7
eggs take up? Probably not much at all. But...those eggs won't
always be eggs. Hopefully, sooner or later those eggs will become 7
beautiful young birds, who, when at the fledgling stage, will be
about the same size as the parent birds. Well, have you done the
math yet? It comes out to 288 cubic inches. You have a rather large
mass of birds when there is a total of 9 of them. A compartment that
only has 6 inch sides only has 216 cubic inches. You just can't fit
288 cu. in. of birds in a compartment that is only 216 cu. in. in
size. A 10 inch gourd has 523 cu. in., nearly 2 1/2 times the size
of the 6" compartment. That leaves 235 cu. in. free for the 288 cu.
in. of birds to freely move around and stretch out.
So I let the engineer in me get a little out of hand. But, stop to
think about it. If I have a bird that is 8" long, the last thing I
would want to do is use any kind of housing that is smaller than the
base bird? Let's say for talking purposes a 6" compartment. That
would be, (for analyzation purposes), about the same as an 8 foot
tall man trying to sleep in a 6 foot long box. He would never be
able to stretch out.
In our case, if the bird goes into the
gourd head first, it has to turn around, and in order for the bird
to do that freely, it would take an area that is a minimum of 8" in
diameter. With that in mind, I would personally not use any kind of
housing that is less than an 8" cube. Now you know why I have
problems with aluminum houses that only have 6" x 6" x 6"
compartments. I also have problems with statements made by the
manufacturers of these houses stating that tests done by them show
that purple martins only need compartments that are 6" x 6" x 6" to
nest. Nobody is going to convince me that 9 birds, that are up to 8"
long, will fit into a compartment that is only 6" cubed. It's
advertising hype and is a way of using less material in the
manufacture of their houses, thus saving themselves money, but at
the birds'expense. And, if they did do the testing, then they need
to redo it, because it's outdated. (And I would like to see the data
and the results. I bet me and my calculator would have a field day
with it). That is one reason why I would never use any kind of
housing that does not have the minimum space requirements of at
And for those that want to know, an 8" gourd has
268 cu. in. inside of it. You probably won't get the larger broods,
but being circular in nature, the birds will still have enough room
to be able to spread out.
It has been proven in studies done
by the PMCA that the larger the housing compartments, the larger and
healthier the broods are. And here's a little different analogy. If
you take a goldfish and put it in a small bowl, it will never get
any bigger. But if you take that same goldfish and put it in a
larger tank, then it will grow to accommodate the tank. So wouldn't
it stand to reason that if I tried to fit two adult birds in a
compartment that is too small for them to begin with, that they will
only raise as many young as will fit in the
Plus, I also feel this way. The whole purpose of
my supplying housing for them is so that my birds can raise as many
young as possible. After all, isn't that the way to get my colony
size to increase? I want them to be comfortable with lots of room to
move around, hence my feelings for 10" gourds.
testing....No, Common sense....Yes.
OK, I know that not all
gourds are 10" in diameter. So, if you only have 8" gourds, then
they meet the minimum requirements, so use them. It's just that the
extra 2" will give the birds that much extra room to move around,
stretch out and relax. And, if you do happen to have an assault by a
flying predator, the birds will at least have a chance to back out
of the way of flailing claws.
Now, one other point. At
present I don't have access holes on all of my gourds, but I'm
working on it, a couple at a time. I believe they are a must for
doing nest checks in gourds. The ones that I do have them on makes
it very easy to get into the gourd to check the young, change any
nesting if required and to do just about any maintenance that is
required inside the gourd. I strongly suggest that these be added to
your gourds. It may take you some time and effort to add them, but
believe me, it's worth every minute spent doing them. When it comes
time to do your nest checks or maintenance, it is so easy to just
unscrew the lid and you have full access to the insides of the
Now for part two of the question, "Why
This is where nest occupation comes into play. It's
a known fact that gourds have up to a 100% occupancy where houses
rarely have more than 50%. That's due to nest site domination by the
males. Male martins will occupy and defend as many house
compartments as possible in the hopes of attracting more than one
female. This usually results in less occupation of the compartments,
especially those with porches, thus again, less young are
With gourds, this doesn't happen. The gourds are
independent compartments and the male cannot usually successfully
defend more than one at a time. This will mean that more birds can
nest and as a result, more young can be raised. So that means if I
have a 16 gourd system, then there is a very good chance that all 16
gourds will be occupied. That means that I will get the most out of
my nesting martins as far as the number of young are concerned. Show
me an aluminum house that can make that claim. And, there is plenty
of tests and data that is available to back it up.
my gourds a lot of work? The answer is... yes, initially. But
remember, this is my hobby. This
is something I do to keep myself busy just like any one else that
has a hobby. So, it's not really work. The birds are only here
during the spring and summer. So, what do I do with myself while
they are gone? If I had just an aluminum house, after I cleaned it
out, nothing. But, I have gourds. So, I grow and harvest and dry and
sand and clean and preserve and paint and prepare. Something I can
do all year long while the birds are gone. I can extend my hobby so
that it lasts all year long, not just for a few months of the year.
And when the birds return in the spring, I am ready for them with
nice, clean, freshly prepared gourds, ready for them to fill with
lots of baby martins.
And, do I have to do this every year to
every gourd? No! Once the gourds are properly prepared, all I have
to do each year is clean them out, and if there is some little
scratch or ding that removed the paint, all I have to do is touch
up. And if I prepare a couple of gourds each year, say 5 or 10, then
I can keep myself busy throughout the year. And if I take my time
and do it right, they should last me for years.
Now, if you
are just starting out, then you will have to do a little more work
than normal, because you have to get them ALL cleaned and prepared.
But, once established, you will only need to do a few each year to
continue the growth of your colony. And you too can spread out your
hobby for more than just a few months out of the year.
now, hopefully you will understand why I like gourds and why I say
that the gourds should be at least 10" in diameter. And, no, not all
mine are that big, but I am working on it. Little by little. After
all, this is my
If you have any comments, would like to send me
another Purple Martin site, or just say "Hi", please click on
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