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Dave Duit
Joined:16 Mar 2019, 00:42
Location:Nevada, Iowa
Original Join Date:Tue Apr 30, 2013 8:02 am

Post by Dave Duit » 20 May 2019, 08:32

This thread is dedicated to all those interested in purple martins. It was created to educate, entertain and enlighten landlords on everything dealing with martins. Each week, two new facts, figures, findings etc... will be added to the end of the thread in a question / answer format. Simply scroll down to see the latest addition. The on going Q&A will number in the hundreds and span over years. We ask that you don't respond to this particular thread in order to keep it streamlined. Thank you.

***************The first 202 questions & answers focus on general martin information. **********************

1. What is the scientific name for the purple martin ?
Progne subis

2. Are all martins completely purple in color?
No, newly fledged males are similar in appearance to females with a whitish underbelly. They
acquire their purple plumage upon their second return from migration. Only (ASY) after second
year adult male martins attain full body purple plumage.

3. Is the purple martin the largest of the swallow family?
Yes. 8 1/2 " in length, a wingspan average of nearly one foot and 56 grams. In comparison, 8
other species of the swallow family in North America weight less at an average of 20 - 25

4. Do Hatch year babies look all identical by the time they take their first flight ? Generally
speaking, yes. The differences are so slight that the untrained eyes has a difficult time
discerning these small varying features in plumage.

5. What do martin eggs look like ?
Pure white with a flat tone and no gloss. Oval in shape and one inch in length and 3/4 inch
width. Soon after hatching the parents usually remove the half shells.

6. What does SY mean in purple martin terminology? The letters "SY" stand for second year. These
are both male and female sub-adult martins returning from their first migration and starting
their second year of life. If you see the letters SY-M it means second year male, while the
letters SY-F means second year female.

7. Are the eggs always the same size ?
No. Eggs will vary in size in any given clutch. The variance in size is particularly seen in nests
with a sub-adult female.

8. How many eggs is considered normal for the average clutch ?
Four to five is average; but there can be as few as one or as many as seven.

9. Why do some eggs not hatch in a clutch ?
Typically, eggs found unhatched are those originating from a sub-adult female which aren't
always fertile. Another cause is a poor diet of the female due to the lack of flying insects
during periods of cold weather while the egg is being formed inside her body. This is one more
reason for the importance of supplemental feeding during cold weather; it may increase the
chances of a larger and successful clutch. Finally, genetic disorders can be the cause of "dud"

10. Why do some nests have only one egg ?
On occasion, the young inexperienced SY pairs will produce just one egg. Other times these
young pairs are just going through the steps of what it takes to be a parent; they may build a
simple nest and produce no eggs during this first breeding year. The single eggs can hatch and
fledge to be considered a successful nest at this point.

11. What is the average life span of a martin ?
Many estimates have been made; but researchers narrow it from 5-8 years. The oldest known
martin that was banded its hatch year and it's hatch date was known was 13.9 years of age.

12. Do good landlord management practices really make a difference for the martin colony ?
Absolutely YES. A mismanaged house or colony is worse than not offering housing to martins.
Your efforts in mite control, making modifications for good venting, pre-nesting with soft white
pine needles, elimination of English house sparrows and European Starlings, supplemental
feeding on days of below 48 degrees or rain and wind and dry spells with small 1/4 to 1/2 inch
bite sized scrambled eggs (no oil preparation), frozen and re-thawed crickets and meal worms
on a feeding tray or flicking with a plastic spoon, owl guards, starling resistant entrance holes,
weekly nest checks and daily walk a rounds, watching for wing entrapment, adding pole baffles,
maintenance of housing, accurate record keeping, etc... are all important aspects of best
landlord practices. Survival rates increase, martin health improved, clutch size increases. Can
you tell I got a little carried away on this Q & A ?

13. Why did a tree swallow nest in my martin gourd ?
Given the chance and if no other housing is available near your martin colony; a tree swallow
may take up residence in your gourds. Do not allow the tree swallow to nest in your martin
gourd. Simple move that gourd about 10 feet away hanging from a sheperds hook and
continue to move the gourd 10 feet per week until there is a good distance between the martins
and the tree swallows. Another option is to offer a bluebird boxes for the tree swallows. Tree
swallows can be territorial and unwilling to share the area with martins. Be sure your tree
swallow young can exit the bluebird box by including groove cuts in the front interior so they
can climb out of the entrance; as long as it isn't a smooth interior front climb for their exit.

14. Do martins stay year round in Iowa ?
No. Martins are a neo-tropical species that winter in South American (usually Brazil), and
summer in Iowa for the breeding season. You may want to spend time reading "Chucks Purple
Martin Page" link under the"contents" section and click on "The martin Bio page" for detailed
info on martin migration, breeding grounds and specific times spent in Iowa and in Brazil.

15. How does the martin rank in terms of desirable species in America ?
The purple martin has been labeled as "Americas most wanted bird". The martin is the number
one species of bird in the hearts of over an estimated 1,000,000 landlords; all sharing the
passion for the purple bird. In a close second place in the bluebird.

16. Where is the largest concentration of martins that winter in Brazil ?
The largest flocks of martins are found in the state of Sao Paulo, Brazil.

17. Exactly where do most martins flock while wintering in Brazil ?
Other than Sao Paulo, the two cities' centers of Araraquara and Ribeirao Preto and
in parks within the trees next to the streets. Oddly, enormous and ear deafening oil
refineries just off the Brazil coastline are flock gathering locations.

18. Why do they choose the city park and streets full of trees to roost over night in Brazil ?
We must remember that the martins are now in their wintering grounds. They don't use man
made martin houses in Brazil because they are not in the breeding season and have no use for
a cavity to raise their young.The parks and trees offer them their best defense against

19. What do they eat while they are in Brazil ?
They forage the sky for many of the same insect we have here in the US, but they add to
their diet a greater variety of flying insects.

20. Do martins eat insects from the ground like worms and grubs ?
No. Martins are known as diurnal aerial insectivores, meaning they are daytime flying insect
eaters. They are extremely effective in catching insects on the wing.
21. Why do I here about Griggsville, Illinois when it comes to conversations about martins ?
Griggsville has been labeled as the "Purple Martin Capital of the World". But, if you look around
you will quickly realize that many cities and towns in each state have self proclaimed titles.

22. Is it a good idea to lower my housing just prior to severe storms or an approaching hurricane ?
It is advised that landlords lower their housing before high winds hit your colony. It serves a
two fold benefit; first it protects your pole and house and secondly it protects the young
nestlings and eggs from being tossed out. The martins will not abandon their colony if you
lower the housing. As soon as the winds subside, raise the house. DO NOT LOWER THE HOUSE

23. Will the parent martins abandon the lowered house if it is left down for the duration of the
storm ?
No. Their nature is strong to ensure that their nestlings are fed and fledge successfully.
They have been observed feeding the young just minutes before the storm hits. Instinct is
extremely in carrying on their genetics. So, lowering the house just for the storm will not
cause abandonment. You can lower the house down to as little as 5 feet. Just raise it back to
it's original position as soon as the storm passes. You can leave it down for as long as the
storm lasts, even over night. BUT, DON'T LOWER IT AT NIGHT.

24. Why do martins always point toward the direction of strong winds and stay lower to the ground
during blustery days ?
It is a simple case of flight dynamics and maneuverability. One, making it easier to fly. Two,
it easier to forage for flying insects; since insects also move closer to the ground
during strong winds.

25. Is it a myth that martins eat rice down south ?
It is an old myth that has been around for ages. Other birds may eat rice, but martins are
strictly insect eaters. In fact, martins may help the rice growers by eliminating harmful
insects from their rice fields.

26. Will martins battle it out inside a cavity ?
It is common for a second year male to do battle with an after second year male martin in an
attempt to claim this already claimed cavity. This is the time when landlords need to be aware
of possible wing entrapments.

27. What is an insect pellet ?
Adult parents will feed their young a packed small ball of tiny insects such as mosquitoes or
caddis flies. It is formed and held in the adults mouth until this insect pellet is large enough to
feed their young.

28. Definition of a purple martin roost.
An area where martins form congregate colonies to roost or sleep overnight. A roost can vary
in size from a few dozen to many thousands, depending on the location and the time of year.

29. What is an assembling flock ?
This term is used for the time when martins assemble in the fall in enormous flocks as they
near the Gulf of Mexico prior to their migration to Brazil.

30. Do bee keepers need to worry about martins eating their bees ?
Martins rarely eat honey bees. To date, no bee keepers have reported problems with purple

31. What are "black" martins ?
Black martins are not a different species or sub-species. Black martins are simply ASY males
that appear black in color in the right light. At a slightly different angle they can take on a dark
purple iridescent color.

32. What is an ASY martin ?
ASY stands for "after second year". A female or male martin that has returned back to North
America from Brazil for the second time.

33. What is an HY martin ?
HY stands for "hatch year" in the bird terminology identification system. These are the male
and female juveniles that have fledged out of the nest and remain identified the rest of the

34. What is an SY martin ?
SY stands for " second year" of life. These are female or male martins migrating back from
Brazil for the first time.

35. I found dead nestlings in the cavity; what should you do ?
Unfortunately, baby martins can die from a variety of reasons; like cold and wet weather,
mites, gnats, heat, starvation, etc... Remove the dead nestlings. Failure to remove the dead
will only attract blowflies and parasites, causing further problems for the colony. If the nest is
still clean and dry after removing the dead, leave as is; the parents may try to lay more eggs.
Also leave any viable eggs that may still be remaining after you have removed the dead. If the
nest is soiled and wet, remove entire nest contents and put in clean nesting material such as
dry white (soft) pine needles. Return viable eggs if you have any remaining.

36. Are SY parents more likely to lose nestlings during extended cold periods than ASY parents ?
Yes. ASY parents have more knowledge, experience, and parental know-how than the SY
parents. Perseverance and parental instinct are not as strong with the SY parents. This leaves
these nestlings at a greater disadvantage from that of older ASY parents.

37. Do any bird calls like that of a ducks/geese call exist for martins ?
Not currently, but you can try pre-recorded CDs like the daytime chatter or dawnsong.

38. What is the weight of an average martin ?
The progne subis-subis (eastern martin) weighs between 43 to 50 grams; with the ASY males
being the heaviest.

39. How much can the average martin eat in insects each day ?
On average 35 grams, but on a busy day they may eat their weight in insects - 45 grams.

40. What does the term, "martin landlord" mean ?
A martin landlord is a person who promotes and provides a nesting site for purple martins and
has resident martins on their property.

41. What is a fecal sac ?
It is the nestlings feces, or dropping excrement inside a thin membranous semitransparent sac
or pouch, which the parents carry a distance away from the nesting site, dropping it on the
ground below in order to keep the colony and nest cavity clean and sanitary.

42. Will parents consume the fecal sac and why ?
Yes, this occurs only in the first few days after the nestlings have hatched. Since the food in the
fecal sac is not completely digested during the early days of a nestling life, the parents utilize
and recycle it's contents for the nutritional value. As the nestling ages the value decreases and
the parents will begin to drop the sac a distance away from the cavity.

43, One migration journey path takes martins over the Gulf of Mexico, how long does that trip last?
30 - 35 hours, non stop of course.

44. What can you tell me about the ICM program ?
ICM or Intensive Care and Management program should be practiced by all martin landlords.
The basic premise or policies include: Offer a nesting cavity absent of parasites or pesticides,
keep accurate records of each seasons results, pairs, fledglings, arrival and departure dates,
daily monitoring walk unders, weekly nest checks, and provide optimum conditions for the
survival of the martin such as supplemental feeding, heat and cold control vents, etc...

45. What is the fatality rate of a martins' first year of life ?
Only 25 % survive their first year of life.

46. Where do the returning 25% SY martins nest ?
They typically spread out within a 50 mile radius from the place that they were born; which
helps prevent in-breeding among a small population.

47. Why do baby martins jump out f their nest before they are ready to fly and what can I do to
prevent this from happening ?
Young martins will jump for different reasons, the two main culprits are heat and mite
infestation. Before the next season arrives, take time to make air vents near the top of your
gourds or housing. Some people use pvc elbows for vents. Just make sure the rain doesn't
enter the cavity. For mite control, watch the nest closely and do a nest replacement with fresh
soft white pine needles if there are mites present. Do a second check and nest replacement
just prior to 20 days of age. This will break the cycle of the mite. There are many educational
videos and information of nest replacements and venting on the web. Also, check out our link
Chuck's purple martin page.n If a baby does jump, try to replace it back to it's original nest. If
this is impossible due to large colony size, match it will a nest with few babies and very close
in age. The new adoptive parents will likely continue to feed the baby. Do not allow the baby
to just stay on the ground if it is unable to fly, it will die from starvation or exposure. Martin
parents will not feed a baby while on the ground. They will only encourage it to fly from the

48. Why is 48 degrees so important in the world of martin landlords ?
48 degrees is the temp at which insects cease to fly, therefore no food source for the martin.
At this point you will need to provide supplemental food such as no oil added scrambled eggs,
crickets or meal worms on a raised feeding tray near the martin colony. This is especially
vital if the temps stay below 48 for more than three days. I personally start feeding on the
day it turns 48 degrees.

49. Is it really necessary to clean out the martin gourds and houses at the end of the season ?
Yes. Research has shown that cleaning the cavities helps eliminate bird mites that can lay
dormant. It also extends the life of the gourd and housing. Many methods are used to clean,
most landlords pre-soak their plastic gourds in a weak chlorine water solution 1;10 before
scrubbing and hosing out.

50. Is it a good idea to cover my wooden martin house with plastic for winter storage ?
Don't cover your wooden house with plastic because it will cause condensation on the inside
and it will rot faster than if left uncovered. You can use a canvas which will allow it to breath
and it won't cause condensation.

51. Why are my martins plucking the small green leaves from my tree ?
Shortly before the first egg is laid, the parents will line the cup shaped bowl in their nest with
small green leaves for a few reasons. First, it is thought that the green leaves aid in further
protection from the eggs rolling around. Second, the leaves may offer a natural insecticide to
reduce the numbers of mites and parasites. Third, the parents can cover the eggs with the
leaves in order to hide them from the prying eyes of predators that look inside the nest. It is
good practice to plant a tree that offers small leaves within 50 feet of your colony. If you pluck
a handful of leaves and place them on your raised feeding tray on a calm day, martins will
take advantage of this nice gesture and utilize the the leaves for their nest.

52. What should I do about an injured baby martin ?
It is best that you try to get that baby to an avian rehabilitator as soon as possible. If you try to
return the baby to the nest and it is repeatedly rejected, it can be force fed with insects, egg
yolks, pellets of lean ground hamburger or soaked "Science Diet" feline maintenance dry
cat food. Trying to take care of an orphaned baby bird on your own is a last resort tactic;
because the baby has no crop to store the food and must then be feed every 1/2 hour for 14
hours per day. Mistakes can be made such as trying to give water through an eye dropper.
There is a strong chance that the water is misdirected into their wind pipe, you risk the
chance of allowing water to drain down their wind pipe and filling their lungs with
water. The parents are the best bet for the babies survival if you can get it to stay in the nest.
Parents will not feed the babies once on the ground. If you are unsure of which nest to return
the baby, match their age to a nest with similar ages with four or less babies. If you mismatch
the ages, you run the risk of that baby dominating the entrance and not allowing the other
babies to get food. In sum, return the baby to the original nest, if rejected, place the baby in a
similar aged nest for adoptive parents, last resort is to try feeding the baby yourself.
A Martin Rehabilitaion Manual number 83012 by Caryle Rogillio can be purchased at:
The Nature Society
Purple Martin Junction
Griggsville, Illinois 62340
Phone: (217)833-2323
You can purchase the book now before such a future event may arise.

53. Where is the largest martin "roost" in the United States ?
Metairie, Louisiana at the southern end of Lake Ponchartrain Causeway Bridge. Being the worlds
largest over-the-water bridge giving it plenty of area for an estimated 250,000 martins in the
month of June and July. It acts as a safe place for the martins to avoid owls, cats, raccoons and

54. What is a brood patch ?
An area on concentrated vascularized cellular structuring on many small blood vessels or
hyperemia which gives heat from the incubating female parent and the eggs or nestlings.
During this time, her abdomen is sparsely feathered which allows the heat transfer to be
optimal. Only the female will develop a brood patch. The male will assist in keeping the eggs
and young warm during her short trips to forage food for herself.

55. Does a martin have a gizzard ?
Yes, it acts as a muscular second stomach. The parents will feed their babies tiny bits of
crushed eggshells, or small pebbles. The gizzard helps in breaking down the exoskeleton of
insects. Offer cleaned, microwaved small crushed eggshell bits on a raised feeding tray or
platform near your martin housing; they will benefit from the calcium and act as grit.

56. Why do martins seem to contort their bodies in strange positions while on a perch ?
They are sunbathing. Martins will expose their bodies perpendicular to the sun, lean to one side,
roll their head and stretch their throat feather and close their eyes, then stand in a deep
motionless trance. It is believed that this sunbathing behavior and positioning allows the heat
of the sun to drive down the bird mites from the face and neck to the stomach area. This
enables the martins to preen and get rid of some of these nasty mites. Sunbathing alone will
not rid the martin of all mites; this is why it is important to do nest changes when mites are
present and the babies are less than 20 days old.

57. Can you define "Ornithology" ?
The study of bird life. A person that makes a scientific study or teaches others about birds
would be considered an Ornithologist.

58. What does the term mate guarding mean ?
A male purple martin behavioral act in which he stays close to the females side while she is in
her fertile period. He in turn is increasing his odds that he will be the only male that will
fertilize the clutch of eggs. This behavior is seen through the nest building and egg laying
stages. Regardless of her actions, the male will be diligent in guarding her from other males.

59. When do male martins attain their full purple plumage?
The feathers of the male martin attains a purple bluish iridescent plumage upon his second
migration to Brazil.

60. Can you give the details of molting for the martin species ?
Martins molt annually beginning in late summer just prior to their migration south. But, their
molting is slowed during their flight and almost comes to a complete stop. Then, when they
arrive to their destination in Brazil, the molting process restarts and continues until they have
completely shed their entire coat of feathers. The molt serves to rid them of nearly all mites
they may have had in their winter breeding grounds and it prepares them for the huge journey
from Brazil back to their nesting grounds.

61. Why do martins preen their feathers ?
Preening keeps their feathers in top notch condition which in turn assures them of easier flight
to catch their prey of flying insects. It assist in keeping them healthy and sanitary.

62. What is the crissum and how does it aid in identification of female martins?
An area shaped like a triangle noticed on the female martins between the anal opening and the
tail feathers base. By looking close you, will see that the crissum of an ASY female
will takes on a dusky edging on the feathers, whereas the SY female
crissum is vivid and white in appearance.

63. Can you explain porch dominance and what can be done to lessen the aggression?
Porch domination is an inherited behavior seen in young male martins in which aggressiveness
to claim and defend nearby nest cavities is on display. To reduce such unwanted behavior in
a colony, a landlord should offer larger cavities around 12 inches deep. Also, add porch dividers
in metal or wooden martin housing. A housing design with small 6X6X6 inch cavities that lack
dividers will rarely exceed 60% occupancy.

64. What happens when a predator bird is seen by martins near a colony ?
Mobbing behavior occurs in the colony. The first martin to see a hawk or owl near their colony
will vocalize a loud alarm signal which alert not only the martin colony, but all birds in the
area of the threat. The females and young yearlings will immediately rise high in the sky and
fly in a circular rotation, while the older males begin strafing and pestering the predator. The
vocal alarm will continue until the threat is a good distance away from the colony. This mobbing
behavior upon the hawk or owl shows us that there is safety in numbers. If there are tree
swallows nearby, they usually will be the first to let out an alarm vocalization.

65. What is "Mixed Reproductive Strategy" or "Forced Extrapair Copulation ?
This is an act by ASY males after they have already established their pair bond and successfully
carried on their paternity. Next, forced copulation upon a younger female takes place.
This act is sometimes forcible by the ASY males; with their intention to fertilize the younger
females eggs. This in turn leaves her unknowing mate and herself to raise the ASY males
offspring. This sounds like a bad situation for the colony; but nature has a strange way of
creating unexpected outcomes. The upside to this strategy is that studies have shown that these
eggs are more fertile and it assures a thriving, healthy and growing colony.

66. What is a penultimate egg ?
The next to last egg laid in the clutch.

67. What percent of time does the male martin spend incubating the eggs ?
More studies need to be done, but observations show that males dedicate about 25% of their
free daylight hours on the nest.

68. What is the time range for the eggs to hatch once the last egg is laid ?
14 to 17 days, but weather might slightly fluctuate this range.

69. What triggers the incubation of the eggs ?
When the penultimate or (next to last egg) is laid.

70. When do martin babies start to chirp ?
At a week old you can hear the nestlings if you are doing a weekly nest check, but it is too faint
to be heard while the housing is raised.

71. At what age do nestlings open their eyes ?
At 9 to 10 days of age.

72. Why is important to stop nest checks when martins reach 20 days of age ?
After the 20th day of age nestling should not be checked. They now have a natural
instinct to avoid any possible threat and therefore may jump out of the nest to early. If you
return this jumper, they may try to jump again before they are ready to fledge.

73. Can a healthy nestling at 12-14 days of age, with ample food and no mite infestation, really
weigh the same as their adult parent ?
Yes. they gain weight quickly and attain this equal weight at 12-14 days of age.

74. Does a nestling preen before they fledge ?
Yes. A nestling will begin preening in the nest at two weeks of age. Their instinct is to keep
clean and healthy. But, two days before they fledge they have a tendency to drop feces around
the entrance. It is believed that since they are close to flight, their brain may be changing
toward more of an adult. Adults drop their feces while in flight or on a perch wire.

75. At what day does a female stop brooding the nestlings ?
If the nestlings are healthy, the female usually stops brooding activity around the 10th day.

76. Why do two week old nestling have a whitish dander covering their body?
This is normal for the nestling as they are shedding their disintegrating feather sheaths.

77. At what time do the parents decide to end roosting with the nestlings in their compartments?
When the nestlings can maintain their normal body temperature at age 11-14 days. Parents will
use a compartment next door or near by if empty. It is believed they do this to provide a more
comfortable living space with the growing size of the clutch.

78. When does a nestling's weight reach it's peak ?
At roughly 18 to 20 days the nestling will weigh close to 60 grams; 10 grams heavier than the
average ASY adult. After the 20th day this weight drops down because of the energy expended
in growing feathers. By the time they fledge they have a body ready for hunting flying insects.

79. At what age can a nestling re-enter their compartment if it accidentally wanders or falls out on
to the porch ?
At age 15 to 16, a nestling that hears an alarm call from their colony of an approaching threat
will scramble back into their compartment an position itself near the near until the threat
is gone.

80. Can a nestling fly at three weeks of age ?
They can fly short distances, but are unable to sustain flight at three weeks. For this reason,
monitoring of a nest with nestlings over 20 days of age is discouraged. The nest check after
three weeks may encourage the nestling to prematurely fledge. Under special circumstances
and following specific guidelines set by the I.C.M program is the only exception to this rule.

81. What is the normal body temperature of a healthy purple martin ?
108 degrees fahrenheit.

82. Will a smooth floor without nesting material be hazardous for growing nestlings ?
If living conditions such as this are left unchanged, the young nestlings legs may form leg
splaying. Their legs will stay permanently at the wrong angle for life. It is important that
landlords prevent a living cavity from having smooth floors without a source of traction.
Provide a rough floor either through adding nestling materials or manually scraping the
floor. It is also important to add a rubber traction strip to plastic gourds with tunnels to allow
for easy access in and out of the gourd. Other alternate methods have been used to provide
traction on floors and tunnels; but it is vital that the method is also safe for the martins.

83. Is a bare metal floor dangerous to martins ?
Yes, especially for young nestlings. Without a sub floor or pull out tray made of wood or other
material other that metal or without the warming and drying effect of nestling material; the
nestlings can die from hypothermia. Bare metal floors will sap out the body heat of a nestling
and is also hard on adult martins.

84. Is it unusual to see a male martin with white patches ?
It is not unusual to see a white patch on a male martin. Some landlords are able to identify a
particular male martin each season due to a white patch.

85. Can you explain the magnetometer or internal guidance system that purple martins use to
migrate to Brazil and back ?
Like many migrating birds, the purple martin uses a variety of instruments to guide them back
and forth during their migration. Martins will utilize landmarks, stars, polarized light, and
earths magnetic field to guide them in migration. They also take advantage of approaching
weather fronts to assist in their flight. But, their migration is still a mysterious aspect of
martin behavior. Migration timing is thought to be triggered by food availability, time of daily
sunlight and temperature.

86. What insects make up the diet of a martin ?
Depending on your location in the US and the time of year, your martins diets will vary.
But, here are some rough estimates: 35% dragonflies, 27% tree hoppers, flying beetles, low
flying ground insects, 8% moths, butterflies. The remaining 30% are wasps, hornets, fireflies,
greenheads, horseflies, houseflies, flying ants, midges, damselflies and other winged insects.

87. How many days does it take for the female to lay a clutch of five eggs ?
Females normally lay one egg a day and will continue until the clutch is finished. Incubation
starts when the "penultimate" or next to last egg is laid. It should be noted that the female can
hold off for a day if there is inclement weather or a low food supply.

88. What is community cavity nesting ?
In cases of inclement cold weather, it is a behavior of martins huddling and crowding together
in one compartment to preserve body heat. It is vital in fighting off hypothermia. It is good
landlord practice to check on the compartment from time to time to ensure that the entrance
is clear. One martin can accidently block the ability for the other martins to exit. Normally a
blocked entrance during community cavity nesting is either from a overfilled compartment
with the inability of the first martin near the entrance to move or a wing entrapment.

89. What can be done to assist martins in retaining body heat during prolonged cold periods ?
In addition to offering supplemental food near the martins on a raised platform feeding tray;
(no oil scrambled eggs small pieces, crickets, mealworms), a few other tricks may help them
survive. Install a 60 watt light bulb in an adjacent compartment with no nesting material and
close off this entrance. The radiant heat will seep through the walls and keep them warm.
Remember to think safety first. The electric cord should meet outdoor standards to prevent
electrical mishaps caused by rain or moisture. Another idea that has been used are hand
warmers; but they will need to be replaced periodically and disrupting the martins may cause
them to use their energy and lose their body heat. Landlords in the northern states have
added slices of foam insulation to replace existing subfloors. After the cold weather is gone and
prior to nest building, you should replace the original subfloor. Foam insulation over the period
of an entire season may cause leg splaying in the growing nestlings due to the nature of it's
smooth surface. It is best to dedicate a few compartments well in advance of your martins
arrival as a warm compartment. Build the bulb room compartment in advance or add the foam
insulation to all your compartments. Do not put insulation in your bulb compartment. If you
choose foam insulation for the walls of the compartments, be sure they are very secure so
they won't come loose and block the entrance or endanger the nest.

90. Is it possible to get a second brood hatch by ASY pairs in the northern states ?
No. What appears as a second brood hatch is a circumstance in which an early ASY pair raise
their clutch and leaves the compartment, then an SY pair move in a raise their own new brood.
A second brood is rare in martins and occurs only in the southern most region of their breeding

91. Why is running a guy wire from the ground to the martin house or running a perch line from the
martin house to a tree a bad idea ?
Because predators such as squirrels and snakes can easily reach your martin house along these
wires and lines. You can add two poles with a wire that is 15 feet or more from your martin
housing for your martins to perch. Such wires are attractive to martins because they use the
perch wire as a place to be social or preen at the end of the day.

92. There is an old rumor that rubbing an onion on the interior wall of a martin compartment will
attract martins to make a nest. Will that really work ?

93. Can a landlord band the legs of martins ?
The short answer is no. But here is the long answer if you are interested.
It is illegal to band any bird without the proper state and federal permits and bird banding
license. There are strict requirements and those holding banding license are typically
wildlife professionals and scientists. In addition to the strict rules and laws; attempting to
band a bird without proper training can result in a bird being severely injured, loss of a leg,
infection or death. See this web url for additional details:

94. Should I buy a bird bath for my purple martins ?
Martins do not use a bird bath. Martins utilize ponds, lakes and streams to dip their beak into
the water while skimming the surface. They also splash down quickly into the water for a bath.
If you wish to provide a bird bath for other native birds I encourage you to do so. Other native
birds appreciate a clean bird bath, especially when you provide a heated bath in the winter

95. Do martins prefer a specific type of leaf to line their nest bowl just prior to laying their eggs ?
Sixty seven species of tree leaves have been recorded that have been used in the nests.
In addition to tree leaves, martins will also use vegetable leaves; but never enough to damage
the health of your garden. They generally use what ever is readily available in the area, but
those most often used are: willow, maple, apple, aspen, oak, elm, cherry and pear. Some
landlords have actually plucked small leaves from trees and placed them on the ground under
the martin houses or on a raise platform feeding tray to assist the martins in their nest lining.

96. What is the average percentage of martin eggs that hatch ?
The national average is 85%.

97. What is the percentage rate of hatched eggs that fledge ?
Under normal conditions, 80 % of the hatched eggs will actually fledge. Cold wet weather, nest
parasites, blowflies, gnats, etc.. all take a toll on nestlings making it to the fledge stage. Nest
changes at day 10 and day 20 after hatch will typically control these parasites. Supplemental
feeding on wet cold days allows the adult parents an opportunity to bring food to the nestlings
inside the cavity.

98. Do fireworks cause martins to abandon their colonies ?
Fireworks do not cause martins to leave their colony. It is a sound just like any other sound
found outside. Birds adjust to noises in their surroundings.

99. Is it fact or myth that martins have been managed by man longer than any other species ?
Fact. No other bird has been provided and attracted to the man made housing as long as the
martin. Native American groups such as the Cree, Blackfeet, Choctaw, Crow, Chippewa,
Miami and other tribes have managed the martins for years prior to the white mans
arrival in America. The martins provided natural insect control for the Native Americans
and we all continue to benefit from the martins today.

100. What does kleptoparasitism mean when referred to nestlings ?
On occasion, nestling will wander out of their compartment just before they are ready for flight
and slip into an adjacent compartment with smaller nestlings. Once in the neighboring
compartment, they begin to deprive food from the nestling and at times cause these smaller
nestlings to starve. in gourds this problem does not occur, but does occur in martin houses
without porch dividers. By installing porch dividers you virtually stop the possibility of
kleptoparasitism. On word of caution is to not install dividers for compartments measuring
6X6X6 inches. It is best to remove the middle partition in the compartment to create a cavity
space of 6X6X12 inches, then add a porch divider.

101. Are all martins one species ?
There are three types of purple martins.
The purple martin east of the Missouri River (progne subis-subis), makes its home in man made
houses and gourds.. The purple martin of the desert southwest (progne subis hesperia), makes
his home in cacti and are slightly smaller. Finally the purple martin of the pacific northwest
(progne subis arboricola), makes its home in tree cavities with a small percent beginning
to take up residence in man made housing.

102. What is a purple martin's wingspan ?
15.5 to 17.5 inches depending on the sub species.

103. What does this big terminology mean, " Poycogenetic Biological Disorder Syndrome" ?
A condition of any of many maladies which occur with purple martin nestlings. Splayed legs,
continuous predator harassment causing insecurity, uncontrolled nest parasites causing
premature fledging or death, poor house maintenance, purulent bird pox are all examples
causing this condition or state. Thankfully, all of these problems can be prevented if landlords
practice good colony management procedures.

104. Why do adult martins become extremely excited, loud and chase a fledgling on it's first flight
from it's cavity ?
This is an inherent natural behavior, mimicking the mobbing behavior. Adults can be seen
chasing the first flight fledgling in the air to a nearby tree or even back to the colony during
this time. The purpose is to force the fledgling to learn quickly the dangers of the world outside
their cavity. They chase the young fledgling to ensure a fast learning curve in its ability to
escape from potential predators such as sharp shinned and coopers hawks in the future. It is
tough love on the part of the adults toward the young to increase its chances of surviving.

105. Was there ever a first official commercial purple martin house manufacturer in the U.S. ?
In 1883, Mr. Joseph Warren Jacobs from the town of Waynesburg, Pennsylvania made a variety
of elaborate wood houses. They ranged from twenty to seventy eight rooms.

106. Will martins make faint chirping noises at night while in their cavity ?
This is normal behavior for martins. We think that it indicates that all is good in the household.

107. Is it true that the natives in Brazil consider the purple martin as a noxious pest and therefore
thousands are killed each year ?
This is a rumor that has surfaced over the years and it is completely false. In fact, the
"Brazilian Association of Preservation of Wildlife", has created a massive public campaign to
educate the people of Brazil of the many beneficial advantages of martins while in Brazil. After
interviewing many of the citizens of Brazil, the conclusion was universal praise for the purple

108. Left alone, will a martin survive two weeks of temperatures at 40 degrees ?
No. Cold and inclement weather take a large toll on the martin species. The best method for
helping martins survive in such conditions would be to add a light bulb to an adjacent
compartment to allow radiant heat to warm the martins. Close off the bulb room compartment
and add a slice of styrofoam to the martin room, but be careful not to block the entrance. After
temps are above 50 degrees you can remove the bulb and styrofoam. In addition to a source
of heat, supplement feeding is very beneficial for the martins. Many raise platform feeding
trays can be purchased online or you can make your own feeding tray. Offer crickets, no oil
added small pieces of scrambled eggs or meal worms. On very bad weather days you can place
the food right on the compartment porch, but do not block the entrance and check on a daily
basis to blocked entrances or entrapped martin in the entrance. Martins will bundle or huddle
together on cold nights in one compartment. If over capacity a martin may become trapped
at the entrance; blocking the other martins in, only to die from starvation.

109. Do great crested flycatcher nest in martin housing ?
Very few cases have been reported on these flycatchers taking up residence in martins houses.
They have been seen nesting in bluebird boxes with larger entrances and in tree cavities. If a
flycatcher is seen around your martin houses, just provide "proper" housing for these beneficial

110. What temperature do martin eggs need to be in order to start and continue incubation ?
At 99.5 degrees F, the eggs will being to incubate. The brood patch on females ensures this
mark is met since an adult martins body is 108 degrees F. Cold weather and early laying
sometimes will cause eggs to be chilled and therefore unable to hatch. The brooding female
will make hard decisions in these conditions; feed herself to survive while having to leave
the eggs unattended, causing a failed nest.

111. What does it indicate when you see adult martins on the ground and unable to fly ?
Unless a landlord practices good management by offering supplemental food on a feeding tray
such as crickets, no oil prepared small pieces of scrambled eggs or meal worms during
extended days of cold and rain; those flightless adult martins are in starvation mode. Pectoral
muscles used to fly will atrophy during starvation, causing them to become unable to fly and
therefore death will occur soon after.

112. Which will kill a young nestling quicker, excessive heat or extreme cold ?
Data indicates that cold weather will show greater loss than heat. Nestlings are only able to
supply their own body heat after 11 days of age. If cold weather hits before they are 11 days
old, the parents highest priority will be to keep themselves feed first. Otherwise, both nestlings
and the parents would die and the colony as a whole would suffer the greatest fatality. Again,
the best way to prevent this tragedy would be to offer supplemental food near your martin

133. Will a male take over incubation duties if the female is killed ?
Usually the male will abandon the nest. If he is able to attract another female, that female
will take over incubation.

134. Do many martins get hit by cars or trucks ?
Martins are agile flyers and under normal highway conditions they are able to easily maneuver
the cars and trucks.

135. Where is the largest purple martin tower located ?
The largest martin tower is located in Lake Charles, Louisiana. It is 120 tall and has
1,116 cavities. They Condo tower in Griggsville, Illinois is also a very large martin tower.

136. Can martins fly backwards ?
No. But they can hover and drop down in the breeze while foraging for insects; which makes
it appear as if they are flying backwards. The hummingbird is the only bird able to truly fly

137. In severe rainstorms, do martins stay out longer than other swallows ?
Martins do stay out a little longer than other swallows only because they are heavier and larger
than the other swallow species. They can sustain and negotiate flight in storms and wind
with little difficulty.

138. Do martins hearing ability lessen due to the noise made from rain on metal housing ?
No research has been done on this topic. Martins do have the ability to close their ear lobes to
assist in dampering the noises.

139. How can I distinguish a martin from a starling at a long distance ?
If on a wire the starling is thicker in the mid region. The outline of a martin on the wire will
show half the body located below the wire, whereas the starling body will be above the wire.
Martins are more relaxed in their posture and the starling will appear to be more on edge,
nervous and display quick jerky movements. At a closer distance you can notice the martins
forked tail.

140. If a clutch of nestlings dies early in the season, will the parents re-nest and try again for
a new clutch ?
Starvation and cold weather will be the most likely culprit in nestling deaths. Baby martins
can't supply their own heat the first 10-11 days. It is possible for parents to re-nest and have
a second clutch if the first clutch died in the early season. This second clutch is usually smaller
in numbers. It will take at least 11 days or more from the death of the first clutch before the
parents start the second nesting. Warm temps will start a quicker second nesting.

141. What makes martins more vocal on certain days ?
* The male has found his mate.
* A warm clear sunrise promises a good day of juicy bugs.
* Eggs starting to hatch.
* More SY males returned from migration.
* Predawn means the dawnsong.
* Nestlings just starting to fledge.

142. Can I use wood shavings for nest replacement or pre-nest material ?
Yes. But, be cautious of overly course shavings or high percent of dust. Shavings has been said
to act as a natural parasite reducer. Another excellent material is soft white pine needles
because they have the ability to wick away moisture after a rain. Some landlords cut the
longer white pine needles to a suitable length.

143. Do purple martins have a good sense of smell ?
Most species of birds in general have a poor sense of smell. martins' smell is a sense that is
not developed like we see in the mammals.

144. Does dry and hot weather cut down on available insects for martins like that of cold weather?
Dry hot weather will reduce the food supply for martins, but cold weather is the greater evil. It
is a good habit to supplement feed on both dry hot days as well as cold and rainy days.

145. How do I help martins by installing a light bulb in a center compartment ?
During long cold stretches martins can suffer from hypothermia. In addition to supplement
feeding you can either buy a insulated martin house, usually found in the northern states and
Canada or install a 60 to 75 watt light bulb in the center compartments on metal martin houses.
You must plug that light bulb compartment and be sure there is no nestling material that
may catch fire. You must use outdoor electrical equipment only to avoid shock or death. The
bulb will produce enough radiant heat to warm the adjacent compartments.

146. How fast will a day old nestling grow ?
A newly hatched egg in the morning will nearly double it's size by the first days nightfall. After
a few days the rate of growth is less obvious.

147. I noticed SY pairs that was not as interested in raising their young as the ASY parents. Why?
Their paternal instinct is not as developed and strong as the ASY parents. The urge to migrate
before their young fledglings are fully independent and the pull of the growing shorter days
near the end of the season also cause their parenting to wither away.

148. What could be the cause of white underfeathers on returning scouts ?
When older scouts return from an especially hard migration due to stress, weather, exhaustion,
cold or illness, they will develop white downy under-feathers. You can help them by offering
supplemental food upon their return such as: (no oil added scrambled eggs, crickets, and frozen
and re-thawed superworms or mealworms).

149. Will an adult martin try to eat a small humming bird ?
No. A martin knows it's food and would not mistake a hummingbird for an insect.

150. Is it ok to place a bat house on my martin housing or pole ?
It is NOT advised to place a bat house on your martin housing or pole. The bat house would
make it difficult to lower your martin housing for weekly nest checks and it would add weight
to your set up. If you want to put up a bat house, place it away from your martin house so it
won't interfere with a clear fly zone for your martins. I would also like to mention that bats do
not take up residence in martin housing.

151. Do SY pairs lay eggs ?
SY pairs will either play house and build complete nests, but may not lay eggs. In some cases,
SY pairs will follow through and lay a single egg and fledge it the first year. SY martins vary
in their maturity and paternal instincts. Unpaired SY males can cause trouble within a colony,
but are usually managed by older males.

152. I have seen some landlords put hay clippings and soft white pine needles on a raised platform
near the martin housing, what are they doing ?
These landlords are providing the paired martins with nesting materials. Some landlords even
provide small green leaves for the martin parents to line the nests just prior to egg laying.

153. I had many pairs in the past years, but over the last 5 years they seem to be going down in
numbers. Why ?
A slow decline may indicate that the growth of smaller sapling trees years ago have grown to
a size that warrants pruning. Some landlords don't realize the fast growth of trees near their
colony and before they know it, the trees have now decreased a clear flight path. If you
remove the trees altogether or scale back the size of the trees, this should increase your
martin population to earlier years. Another option if you have a large yard is to slowly relocate
the martin housing a distance from the trees, about 10-15 each year if feasible.

154. Is it really necessary to keep records on everything about your colony ?
The martins won't be aware of your records, but actions to improve the colony based on your
records over the years will improve your martin numbers. Records are only as good as the
landlord follows through and takes steps to either make changes or improvements to
the colony housing and practices. Records will in turn allow the landlord to be more aware of
what is going on within the colony. With routine weekly nest checks, you are more likely to act
on things such as a capped eggs, or removal of dead babies, or treating for bird mites. Records
will indirectly make for a healthier colony.

155. A climbing flower vine would look nice at the base of my martin house pole, is this alright ?
No. Any type of shrubs or climbing vine at the base or near the pole only encourages a
hiding place for cats, raccoons, snakes, etc... to stalk your martins.

156. On hot days I noticed my martins splash down belly first in the near by pond and quickly
return to the nest. What is this behavior ?
It is called belly soaking. If the nestlings are not feathered, not old enough to breach the
entrance and the temp is above 95 degrees; the parents will belly soak and return to the nest to
spread the belly water on the surface of the over heated nestlings. This action will in turn
cause a cooling effect for the young through the process of evaporation.

157. Will bumping the martin house pole with the lawn mower disturb the martins ?
The bump will not cause the martins to abandon the nest, but you should avoid this bumping
because the martins will feel this inside their nesting cavity and interpret it as a predator or
threat. To best avoid bumps, when cementing the pole in the ground you should spread out the
cement about 10 inches to eliminate the need for the mower to get close to the pole base.

158. What does single brood refer to with martins ?
Single brood is a avian term used for any bird species that has only one set of eggs per season.
The purple martin species is a one brood bird. There are only very rare occasions in the
extreme southern breeding ground that might have a second brood; but this is not normal. If a
pairs first brood are very early in the season and it fails, the pair will on this rare occasion
attempt a second brood.

159. Martins breed in all 48 contiguous states, right ?
Wrong. Martins breeding grounds are in all except: Idaho, Montana, Wyoming and Nevada.

160. If I have a colony of martins, will I be able to attract other birds in the yard ?
Purple martins are compatible with other native species of birds. Just don't allow sparrows
or starling in your colony. Relocate tree swallows if they move into your compartments.

161. Do martins have a hard time crossing the Gulf of Mexico during their migration ?
Generally the martins do just fine on the 600 miles journey over the Gulf. But, tropical storms
and strong headwinds can make some years difficult.

162. Do martins drink salt or brackish water along the Atlantic Sea Coast ?
They prefer fresh water, but have been observed drink brackish water. Since martins don't
have salt excreting glands like seabirds, it is assumed that they could not live on salt water

163. What is the maximum temperature at which a nestling fails to survive ?
At 106 degrees inside a compartment, nestlings will die. You can provide added vent elbow in
the back upper third of your gourds to help keep temps lower. Other landlords have had
success in lowering compartment temps by offering a roof or shade above the housing. Misters
near the colony, but clear enough to NOT ALLOW MOISTURE to enter compartments will allow
adults to cool down. Mister will not aid nestlings in cooling.

164. Why do first flight nestlings seek out the nearest tall tree once they fledge ?
Fledged nestlings will fly to tall trees, first because they offer better protection from hawks and
predators. Secondly, The parents will continue to feed the young in the tree for a while.
Nestlings will return to their compartments near dusk for the next two weeks. During the two
weeks, the youngsters go through a training by their parents on foraging and catching insects.

165. Can martins eat 2,000 mosquitoes each day ?
The martin can eat 2,000 per day, but they don't. The mosquito makes up about 1% of their
total diet. Certainly, the martin "can" eat this many but they simply prefer larger insects like

166. How rare is a true albino martin ?
Rare, about 1 per one million martins are true 100% albino. Albinism is mostly seen with
robins; but is still rare for this species.

167. I've heard of ASY (After Second Year) males, but what is a TYA purple martin ?
When ever you see these letter synonyms landlords are refering to the age of a martin. A TYA
is a (third year adult) male. They are of full purple plumage, but they have not reached their
full physical chest size. Older ASY males bulkier, whereas the TYA male is sleek and slender.

168. Why is there a difference from evening to evening when is comes to the level of chatter
inside the gourds ?
There are a few factors at play. During warm weather they stay up later and are more vocal.
During colder weather they tend to bed down earlier and are less vocal. A second factor is if
the colony lost a member due to a hawk attack, which in turn makes them more alert and
quiet to listen for any returning predators. A weather pattern of warm sunny days causes them
to stir with anticipation of a good insect foraging day, while cold weather causes the opposite

Dave Duit
Joined:16 Mar 2019, 00:42
Location:Nevada, Iowa
Original Join Date:Tue Apr 30, 2013 8:02 am


Post by Dave Duit » 15 Jun 2021, 13:20

just bumping

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