What to look for!
What to do!
Because of recent research on purple martins,
it's now a known fact that birds that are tended by their landlord
do much better in rearing young and on my web page, I highly
recommend that landlords get involved and do these nest
checks. However, two questions I'm asked a lot from people
that read these statements are, "How often should I do them and what
do I look for?" In this article I'll try to explain what to
look for and what to do when something wrong is found.
First, let's ask another question. "What are we
trying to accomplish by doing nest checks?"
Well, there are a number of things. Nest checks are
an integral part of keeping and hosting purple martins.
Because eastern martins are now totally dependent on us humans for
their housing, and with all the things that can go wrong in a
colony, it behooves us as landlords to know what's happening
with our birds. Plus, if there is something amiss in our
colony, then we need to be able to first identify and then correct
the problem before things get worse. This could be any number
of things from simply finding a perfectly normal nest to cracked
eggs or a dead baby to possibly finding a nest full of mites or
blowflies. You could even find out why a pair of martins is
hesitant about entering it's cavity.
The days of being a 'passive' landlord are pretty
much over. A 'passive' landlord is one that simply puts his or
her housing up and then ignores it for the remainder of the season,
letting the birds do their own thing. This form of martin
hosting is no longer valid and with all the pests and predators that
are around a colony today, we as landlords have to change.
That means becoming an 'active' landlord, taking an active
interest in the colony and the birds and educating ourselves so that
we are able to deal with any of the problems that could occur in our
colonies. Hosting purple martins is sort of a hobby and
hobbies are made to take part in.
This article assumes that you have the proper housing
that is easily accessible. If not, now is the time to
change. (In fact, ANYTIME is a good time to change).
When the birds are gone for the winter, incorrect housing should be
either reworked or replaced with some that is. This also means
that gourds should be reworked so that access ports are added, or if
you have small gourds, then they should be replaced with some that
are 9" or 10" plus, and while you're at it, might as well paint
everything nice and white.
Nest checks are very easy to do, plus, they are also fun
and interesting. Once a landlord gets over the fear of scaring
off his or her birds by invading their nests, then doing nest checks
will become second nature in a very short time. Some of the
old ways are dying hard, but once we break through the myths that
have been handed down through the years, the fears quickly
dissipate. And, if we get the young involved early in life,
they too will learn to respect and protect nature without being
afraid of it.
One of the things you'll need to do is keep good records
and to do this, you'll need is a good data sheet. No, these
sheets aren't totally necessary, but since you're going to be into
the nests, there's no reason not to keep good records. If a
colony gets large enough, it becomes very difficult to remember all
the things you've seen and where you saw it. Plus, if these
data sheets are accurate and well kept, they are highly prized by
organizations like the PMCA, and making a copy and sending it to
them will help out immensely in their collection of data for future
research. It's another tool that can be used to find out more
about the species as a whole.
The data sheets are readily available from the PMCA and
contain all the columns for data a landlord will need. They
can be had simply by printing them from their web page http://www.purplemartin.org .
Once you have a few of them, get yourself a clipboard to put them
in. Makes it easier to write on. I also add a few 'note'
sheets to my clipboard. On these, I jot down notes of things
of interest that I find in my colony. You'll also need a
'Prognosticator'. They can be gotten from the PMCA as well and
will save hours of calculating. Check out their web page.
One more thing you'll need is a 12" long piece of 1/4"
diameter wooden dowel. Sharpen the end of it almost to
a point like a pencil. This will be used to push things around
in the nest and believe it or not, this is a much better method than
using your fingers. Much easier to control plus, it's a lot
easier to see by than trying to see around your hand. I
drilled a small hole in the end of mine and tied a long string to it
and then tie it to my clipboard for safe keeping so I don't lose
it. During nest checks, I either stick it in a pocket or
simply keep it in my hand. I also made a small, light table
that I can carry out to the site. I use it to set my clipboard
and other tools on when I'm needing two hands somewhere else.
Saves bending down to pick it up all the time. Those little
portable folding lunch tables will also work just great for
And one last thing. Don't forget to number your
compartments. It's the only way you can keep track of which
nest is which. I use a large black 'Sharpie' to number all of
There are really two different steps to doing nest
First, there's the checks that is done from a
distance. These are known as 'walk-unders'. That
means studying your colony without actually getting into the housing
and observing their actions under normal circumstances. You
aren't directly involved and you get to see the normal happenings
when they aren't being directly interfered with. I use my note
sheets a lot here. A good pair of binoculars might come in
handy also if you want to study from a longer distance. Every
day a landlord should walk under his colony to see if anything
unusual can be detected from the ground.
From these walk-unders, you'll look at the colony in
general, looking for anything that may seem out of place.
Watch the ground as you walk. A large brown feather found on
the ground could mean an owl attack. Large quantities of
martin feathers and bits of chewed off wings could mean a raccoon
visited during the night. Martins flying about, fussing loudly
and refusing to enter their housing could indicate a snake is in the
housing. Any of these signs would indicate you need the proper
guards in place and pronto or you'll quickly lose your colony if
visits from these predators are repeated. Snakes will usually
visit later in the season when eggs and young are present and once
in your housing, won't leave until every egg and baby are
gone. Untold numbers of colonies are lost to these predators
every year because the landlord failed to employ proper predator
guards. And it's not the snakes fault, it's only following
its' instincts in finding food. All ground based predator
attacks can be prevented by simply employing a workable pole mounted
predator guard. This is a responsibility that we as landlords
must accept if we are to host purple martins.
Second, there's the 'direct' nest checks. That
means actually lowering the housing and looking into each
compartment. These are the ones that usually scare a lot of
people because they feel they are interfering with their
birds. But, after doing them one time and watching their birds
return shortly after they've finished, they usually realize that the
martins really don't mind and tend to lose that fear a little.
However, getting landlords to realize this is a never ending battle
and very large numbers of people still believe in the old myths that
directly interfering with their birds is not good.
Walk-unders should take place every day from the time the
birds return and continue throughout the time they are here.
Direct nest checks should begin at the start of nest building and
then continued on a regular basis. Always date your
checks. When using them to refer back later in the season, it
makes it easier to tell when something was going on. I do my
nest checks every 4 days and there is a reason for this. If I
were to only do nest checks every 7 days, for nests that only had 4
eggs laid, I wouldn't be able to determine when the first egg was
laid. There could be a 2 or 3 day overlap there that I
wouldn't know about. But, if they're done every 4 days, then
even the nests with only 3 eggs in could be determined. Now,
this is not to say that every 4 days is a requirement. It's
only a suggestion. Some folks are not able to do them that
frequently or might only be able to do them on weekends.
That's fine too. Just keep good records as best you can.
If you supply nesting material in the cavities like I do,
then you'll have to determine what time you want to begin nest
checks. However, if you watch the birds actions, you'll be
able to tell about when to begin. I also supply a raised
platform with cut wheat straw on it and from that, I can tell when
the birds are working on their nests. Even though I supply
nests full of material, some of the females will add some finishing
touches to their nests and I see them at the platform getting some
of this straw. That tells me nest building is in process.
Begin by lowering the house slowly. Yes, your birds
might fly off making a lot of noise, but if you take notice, they
aren't flying away, but instead, are flying right directly
overhead. Martins aren't like other birds and run and
hide. Instead, they are curious and want to see what you are
doing. Depending on how long it takes, they'll usually find a
perching place and watch. My site consists of 4 racks and two
houses and mine mostly land on another rack or a power line that I
have and watch me. Of course, mine go through it all the time
so the older birds are used to it. So much in fact, that later
in the season, some incubating females won't even get off the
eggs. This is an added treat because it tells me that my birds
trust me and know that I mean no harm to them and that's a good
Since it's early in the season, you can take your
time. There's no eggs or young to worry about so speed is not
an issue. Upon opening the compartment, take note of how
things are going. Check out to see if the original material
you put in is enough. The material will settle down from the
birds walking on it and there should be enough so that the nest
level is right up to, or close to, the bottom of the entrance
hole. If they want to add more, they can. If a female
adds finishing touches to her nest, then make note of what it
is. This might be more material or twigs and of course,
leaves. Take notice of what they are using and generally
what's going on throughout the colony. If there are different
leaves available, make notes of the types. This is where the
'note' sheets come in handy. Although it turned out to be
common sense, I realized that nest building never starts before the
leaves are out on the trees. It was something I never paid
attention to until I started keeping 'notes'.
Look at the nests in general. Do they look like
they are normal? (After seeing a bunch of nests, you'll soon
learn what 'normal' is for a martin nest.) Do they look like
martin nests? Do they look different? If other birds are
building in your housing, this is a quick way of telling that
something is wrong. It is imperative that a landlord be able
to quickly discern what type of nest they are looking at.
European Starlings and English House Sparrows will readily build
nests in martin housing and they must be removed at once. A
quick way to spot these pest birds nests is, both of these birds
will literally fill the compartments with nesting materials and if
they continue to build, then elimination procedures must be taken as
soon as possible.
As the season progresses, take note of the age of the
birds. ASY's, SY's and which are paired with which.
Although not always, mature birds will usually pair together.
ASY males that can't find a mate will sometimes choose a SY female,
or vice versa. There is a place on the data sheets for this
As egg laying begins, make note on the data sheets of how
many and what date it is. This will help determine the date
the first egg was laid. Once this is known, using the
prognosticator, you can now calculate when the first fledglings will
vacate the nests. Not trying to hurry the season here, but
it's a good indicator of how long the nesting season will last, plus
you'll need this information later in the season.
Using your 'poke' stick, gently poke around in the nest,
moving leaves and get an accurate count of eggs. Sometimes the
females will bury them down into the leaves and they are not readily
visible until you move the leaves. Once the count is obtained,
replace the leaves to what the female had to begin with.
Although not critical, I try to leave the nest as close as possible
to how I found it.
Look at the condition of the leaves. Fresh green,
dried green, dried and brown. Sometimes, martins will use
dried brown leaves from the previous year to build their
nests. They aren't always 'fresh' green. These brown
leaves are usually combined with sticks that they find, giving them
a good base to walk on.
Look for eggs that might be discarded from the
nest. These are usually found well out of the bowl and near
the entrance hole somewhere. Check them to make sure they
aren't 'pinned'. Pinning is the results of sparrows getting
into the nests and then pecking holes in the eggs, rendering them
infertile and preventing them from hatching. Sparrows are
notorious for this and it's one reason they must be kept out of
martin housing at all costs. If not pinned, then the female
has determined the egg to be infertile and she has removed it from
the nest. These eggs should be removed from the cavity and
should never be placed back in the bowl. Make note of this on
your 'notes' sheet.
Once your birds get used to your being around, sometimes
when you lower the house, some won't even get off the nest.
Incubating females will often stay right on the eggs while you open
the compartment. If this happens, that's when your little push
stick comes in handy. Use it to gently push her aside or lift
her just enough to count the eggs and then close the compartment
back up. I actually talk to mine in a soft voice while I'm
doing this and many times she'll just continue setting on the eggs
as if nothing has happened.
The hatching of the first young of the year is always an
exciting time. This means that the parent birds will be making
frequent feeding forays to find food and return it to the ever
hungry young. As more and more young hatch, the colony becomes
a frenzy of flying birds, zipping in and out with food. Nest
checks are even more necessary now because the young are more
vulnerable at this time than at any other. New born chicks are
helpless and for the next 28 days are totally dependent on the
parent birds. However, there are a few things that the parents
can't do anything about, but landlords can.
Daily walk-unders are now more important than ever.
As nestlings get older, they often stray to close to the entrance
hole and are sometimes pushed out of the nest and are quite often
found on the ground. If you've kept good records, it can
usually be determined which nest it came from and then be replaced
there. The proper guards in place are now of primary
importance to protect these young from predators that want to get at
During nest checks, there are a number of things to look
for. Keep watch for nestlings that may die. Sometimes,
for what ever reason, some young will die and it's nobody's fault,
just a thing of nature. If small enough, the parents will
usually remove them from the nest. But if they are too big,
they usually end up staying right where they died. Dead
nestlings create a growing medium for some insect pests and must be
removed from the nest as soon as possible, and besides, they aren't
too pleasant to smell after a couple of days in a hot nesting
compartment. Sometimes you'll find very young chicks on the
ground in numbers. Check them out for wounds. Both
sparrows and starlings are notorious for throwing baby martin chicks
out of the nests so that they can't mature. Another reason for
eliminating these pest species from around martin colonies.
Starlings can be prevented from entering your housing simply by
employing crescent shaped Starling Resistant Entrance Holes
Blowflies and mites are the two major problems most
landlords will run into. Both of these insect pests lay their
eggs in the nesting material. In the northern latitudes,
blowflies can be a real problem and in the south, mites. Both
of these pests can literally suck the life blood out of young birds
and if left un-attended, can eventually kill them. To the best
of my knowledge, the only thing that can be done for blowflies is to
replace the nesting material. This is also the 'recommended'
treatment for mites, however, major infestations of mites may
require a couple of nest changes during the season.
Another thing that can be done to control mites is to
apply a small amount, (less than a level teaspoon) of 5% Sevin dust
to the nesting material just inside the entrance hole. Then,
tap the nest to settle the powder down into the nesting
material. DO NOT add directly to the chicks. The
mites will crawl through the dust down in the material and thus, be
The use of pesticides in martin nests is a very
controversial subject. Statements given here are not to
endorse the use of pesticides in martin nests, but are here only to
give a landlord an alternative for treating mites. (Some just
can't stand to have mites crawling all over their hands). It
is suggested that anyone choosing to use 5% Sevin dust for this
treatment should educate themselves fully on the subject of Carbaryl
first. If you do not wish to use it, then please, do the nest
Keeping close tabs on the number of chicks in each
compartment is important. If one of them happens to get out,
then you'll know where to replace it if it's found on the
ground. If for some reason, the numbers change drastically,
then you probably have a predator that is visiting and the proper
preventative measures need to be taken as soon as possible.
One note here:
Every once in awhile a very young live baby will be found
on the ground. If this happens, then the nests should be
checked for predator or pest involvement. If nothing out of
the ordinary is found, then these babies should not be
replaced in the nest. Obviously, the bird is much too young to
get out on its own and if pests aren't the cause, then the parents
are. If the parents deem something wrong with a chick, they
will discard it on their own and you'll find them when you do your
walk unders. Although we may not see anything wrong with the
baby, the parents apparently do and have decided not to raise
it. Unlike us humans, wild birds do not live on emotions, but
instead use instincts that have been passed down through eons of
generations and they seem to know when it's best not to waste energy
and try to raise a chick. When I find these, I usually let
nature take its course and simply discard it. I try very hard
not to let my emotions (Anthropomorphism) take over in instances
like this and try to see it from the birds' point of view.
Their instinct is to spend their energy raising healthy young chicks
instead of wasting it on one that is not healthy.
As the season begins to wind down, keep track of the
dates of the first hatchings. When the young get to be about
22 or 23 days old, direct nest checks should cease. From this
point on, only walk-unders should continue. The reason for
this is that, any sudden shaking of the housing could make the young
quickly vacate the compartments and at this stage, they are much too
young to be able to fly and survive. However, they have enough
feathers that they could get a good distance away from the housing
and you might have a problem finding them to put them back. It
is imperative that the last nest check be a good one, making one
final accurate count and making sure all things in all cavities are
well and that there are no problems. If there are, then they
should be fixed and then let the season conclude without further
It's at this point that I like to spend more time around
and under my colony. The young, although initially shy will
eventually get curious enough to stick their heads out of the
entrance holes and within a short time, see me as no threat and
begin paying full attention to the parents bringing in food.
Then, when they eventually do fledge, they are not afraid of me when
they come back to roost or perch on the housing. I find it
particularly funny at times to watch their antics and see some of
the predicaments they can get into while learning to use these new
found wings. I also keep a camera with a good lens close by
just in case. You never really know what can happen and a good
picture can result from a few of them.
Because of accurate records, you'll know when the last
young have fledged and once that happens, lower the housing and make
one final check. If all is OK, then you can now tally your
seasons' numbers and put your notes in order. I like to punch
holes in mine and keep them in a 3 ring binder. I put my notes
together in an order that I can follow and then use them to refer
back to from season to season. A copy can be made of all of it
and then sent off to the PMCA so that they can be used for research
Hosting purple martins has changed in the last decade and
it is now imperative that landlords get involved with their
colonies. Not only is it good for research, but it's good for
the species as a whole. We now know what's going on in the
colonies and when something is amiss, we are able to correct it
before the problem gets out of hand. And one more thing.
Doing nest checks is fun. In fact, the next time you do one,
invite a neighbor from down the road that has birds and let him or
her join in, especially if they've never done one. There is no
better way to educate landlords than to let them experience things
first hand and before you know it, they'll be doing nest checks
Back to Chuck's Purple Martin
This page created and
by Chuck Abare
The Registry of Nature Habitats
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All Rights Reserved