ENLARGED COMPARTMENTS IN PURPLE MARTIN HOUSES
A CASE OF NECESSITY, NOT HYPE!

Is the number of martins in your colony at an apparent standstill and you have no answers to the reasons why? 

Are you convinced that 6” x 6” sized compartments are perfectly suited to the nesting needs of Purple Martins?

I once was a member of that school of thought, but not anymore! Did you know that nest productivity is largely dependant upon size of the compartment? 

Did you know that you are subjecting the martins you host to great risks including predation and self culling because you offer smaller 6” x 6” compartments in your housing? 

Did you know that your colony’s overall productivity will most likely be affected negatively when you offer smaller compartments? I hope that these questions have stirred your curiosity!

There is much at stake when it comes to your choice of compartment size. The fact is that 6” x 6” compartments are OLD SCHOOL, outdated, and substandard based on the facts that are proven today. Whether you have an open mind or not, GIVE THE FOLLOWING INFORMATION SOME STRONG CONSIDERATION. By the time you finish reading, I am certain that you will be convinced that the ENLARGED COMPARTMENT IS an entry level (but not sole) REQUIREMENT FOR a Purple Martin house today. It will also serve to prove the case that the 6” x 6” dimensioned compartment is nothing more than a relic of the past.

PROVEN PITFALLS OF SMALL 6” X 6” COMPARTMENTS IN PURPLE MARTIN HOUSES.

Here are some potential negative consequences that result from their use.

LOWERED NEST PRODUCTIVITY:

• smaller average clutches (number of eggs laid per nest)
  
• decreased hatching rates of eggs
  
• chick sickness and loss due to unsanitary compartment conditions
  
• altered parenting activities including decreased brooding and protection (this causes the chicks to be subjected to weather extremes)
  
• much greater likelihood  for predation losses in the nest
  
• problems with thermoregulation and chick losses (Thermoregulation is a natural response exhibited by many living creatures ….. including man.  In the case of Purple Martin chicks found within a nest, thermoregulation occurs as the nestlings spread out (if space is available) in order to avoid over-heating.  This spreading out of the chicks within the compartment over a larger area encourages body heat loss during hot days.)

By now, you most certainly are asking yourself “Why are 6” x 6” sized compartments still recommended and used today in martin houses?” There are three known reasons, misinformation, lack of willingness to change, and manufacturing convenience.

Unfortunately, all of the negative factors listed above directly affect the REPRODUCTIVE SUCCESS of nesting Purple Martins. With each of these hazards exposed, it is now time for you discover just how ENLARGED COMPARTMENTS can counter the negative outcomes that are directly associated with smaller compartments.

However, before I do so, I would like talk briefly about productivity.  A few questions are very appropriate here. First, “Have you ever been concerned about productivity in your active or potential martin colony?” If you haven’t, please be reminded that nesting productivity is the very CORNERSTONE for the survival and growth of any martin colony. Without it, colonies of martins will eventually cease to exist. With that said, consider the following words that solidly found the fundamental need to offer ENLARGED COMPARTMENTS in your Purple Martin house.

ENLARGED COMPARTMENTS – VITAL, PURPOSEFUL, AND PROVEN

Over a decade ago, a Purple Martin landlord began to incorporate compartment space in his houses that offered more area for his nesting martins. He found that the use of these large compartments proved beyond a doubt to be very beneficial and that his martins actually preferred them. From that point on, the case for the enlarged compartment was born.  Today, enlarged compartments are only found in PROGRESSIVELY designed, high quality martin houses. An enlarged compartment by today’s standards must meet certain minimum dimensions in order for it to be effective.  Those minimum dimensions are 6”wide x 12”long, measured internally inside the nesting compartment.  Any compartment measuring less than either of these dimensions will prove less than beneficial. Are you ready to learn how enlarged compartments can improve your colony’s productivity and potential growth? Let’s look at the proven advantages in detail.

SPECIFIC ADVANTAGES PROVIDED BY ENLARGED COMPARTMENTS

1. Purple Martins will naturally lay more eggs per nest.

Studies have shown that:
The average clutch size in small 6” x 6” compartments is about 4 eggs per nest.
In the past when I used small 6”x6” compartments, their average was similar, about 4.1 eggs per nest.
 
The average clutch size in enlarged (6” x 12”) compartments is about 4.8 eggs per nest.
That is quite a dramatic difference! “Won’t you agree?”

In my present colony’s houses, ALL OF WHICH HAVE ENLARGED COMPARTMENTS, during the 2006 nesting season, 53% of all martin nests finished the egg laying phase with 5 eggs in them.  Five nests had 6 eggs in them! The key point here is the great potential for increased productivity.

Fact: I have just illustrated by real numbers that instinctively, martins will lay more eggs in more spacious, enlarged compartments.

2. Egg hatching rates are substantially higher.

Martins will build their nests as far away from the compartment entrance opening as is possible.  This is another natural instinct of martins that helps to encourage nesting success. With a small, 6” x 6” sized compartment, there is NO OPTION for the birds to build a nest selectively in the back portion of the compartment. There simply is just no space to do so. On the other hand, in an enlarged compartment (6” x 12” or larger), martins will by instinct build their nests in the back portion of the compartment. THIS AFFORDS GREATER PROTECTION of the nest and the eggs from the weather.  Small compartments simply cannot afford any great degree of protection. Wet nests commonly occur in 6” x 6” compartments and they can have a very serious, negative impact on egg hatching rates. On the other hand, watertight, horizontally deep compartments offer optimal nesting space and conditions. Again, my observations back this fact up.

Over the years as I have observed and recorded hatching rates, here is what I found to be true.

In smaller 6” x 6” compartments, egg hatching rates typically did not exceed 50%. Thus, only 2 out of 4 eggs per nest would hatch.

In my horizontally deep Lakeview Series houses (6”W x 13+” L), egg hatching rates typically are 75 to 80%. In 2006, the average egg hatch rate was 85%! Now that is a BIG DIFFERENCE.

Remember, without productivity, your colony of martins cannot thrive.

3. GREATER PROTECTION FROM PREDATORS WILL BE ESTABLISHED.

Many types of predators frequent martin colonies in search of easy meals. Hawks, owls, and raccoons are some of the main predators that pose a threat to nesting Purple Martins. Compartments that measure 6” x 6” do not offer any protection from these predators. Before you discount this vital point, please realize that Great Horned Owls have a reach of about 10 – 12”. They can easily snatch any martins present in a small compartment.  It is no wonder that owls frequent conventional housing with small compartments! Small compartments afford easy meals.  Raccoons also have good reaching ability and can reach about 10” back into a cavity where nesting martins reside.  They are a REAL threat to any smaller sized compartment.

The bottom line is: Small compartments afford nesting martins NO protection against predation losses.

Point to remember: With predation losses, your colony cannot thrive  and perhaps not SURVIVE.

4. THERMOREGULATION CAN TAKE PLACE.

POINT TO REMEMBER: It should be the goal of every martin landlord to fledge 5 chicks from every nest.

Deadly heat build-up within compartments can and does threaten the survival of the chicks inside.  As temperatures rise, the chicks will attempt to spread out (increase the space between themselves) in order to allow heat escape from their bodies. Now, considering the ideal goal that every martin landlord should strive to achieve, that being to fledge 5 chicks from every compartment, space available in the compartment becomes extremely important. In cramped, 6” x 6” compartments, there is little or no room for the chicks to spread out. Whereas, in enlarged quarters, the chicks will be able to spread out, allowing some thermoregulation to occur. It goes without saying that a healthy chick will fledge. A sick, over-heated one will not.

HERE IS SOME DRAMATIC INFORMATION THAT WILL OPEN YOUR EYES TO THE REAL PROBLEM WITH 6” x 6” COMPARTMENTS! This information is real, and was measured and collected by me. This information paints the true picture about how inadequate smaller compartments are when space and growing martin chicks is considered.
PURPLE MARTIN CHICK SPACE REQUIREMENTS DURING VARIOUS GROWTH STAGES
Age of Chicks – 1 day; space required per chick = .71 sq. inches
  Total space required for 5 chicks = 3.55 sq. inches
 Total space required for 5 chicks plus parents = 23.5 sq. inches

Age of Chicks – 4 days; space required per chick = 1.34 sq. inches
  Total space required for 5 chicks = 6.70 sq. inches
 Total space required for 5 chicks plus parents = 26.7 sq. inches

Age of Chicks – 10 days; space required per chick = 6.42 sq. inches
Total space required for 5 chicks = 32.1 sq. inches
 Total space required for 5 chicks plus parents = 52.1 sq. inches

Age of Chicks – 16 days; space required per chick = 8.7 sq. inches
Total space required for 5 chicks = 43.5 sq. inches
 Total space required for 5 chicks plus parents = 63.5 sq. inches

Age of Chicks – 21 days; space required per chick = 9.5 sq. inches
Total space required for 5 chicks = 47.5 sq. inches
 Total space required for 5 chicks plus parents = 67.5 sq. inches

DON’T MISS THE NEXT POINT!

A 6” X 6” COMPARTMENT ONLY OFFERS 36 square inches of space.  My Lakeview Series houses offer 78.75 square inches of space.
As you can see, the numbers paint the real PROBLEM WITH 6” x 6” sized compartments.  By the time that the chicks reach 10 days old, there is not enough room for both the parents and 5 chicks to roost at night in the same compartment. Even more serious is the problem that arises at 16 days. At that point, a  6” x 6” sized compartment(area = 36 sq. in.) is not EVEN LARGE ENOUGH TO PROVIDE AMPLE SPACE FOR ALL 5 CHICKS!!! Due to the fact that the chicks will not fledge for another 10 – 12 days, this situation becomes a very serious problem as I will later explain.

5. NATURAL PARENTING ACTIVITIES CONTINUE WITHOUT DISRUPTION.

 By instinct, both martin parents prefer to roost at night in the same compartment with their young. This instinct helps to increase the survival of each chick. Enlarged compartments do not disrupt this process because there is ample room throughout the entire nesting process. However, there is a major space problem in small 6” x 6” compartments after the chicks reach 10 days of age.

6. PREMATURE FLEDGING AND NATURAL CULLING ARE GREATLY REDUCED.

It is a fact in the world of nature that natural controls govern some aspects of nesting martins. With cramped and overcrowded conditions in a 6” x 6” compartment, it just goes on to follow that some chicks in this situation will not survive.  Some chicks may be forced from the compartment by their siblings as the demand for more space increases. Others will attempt to survive by fledging too early. In most cases, these chicks do not survive either. Still others will not fair well with the overcrowded, unhealthy conditions and will weaken, get sick, and eventually die. This is mother nature’s way of culling. But, by no means should this be an acceptable solution given that there is a very viable option….. THE ENLARGED COMPARTMENT. With the ample space provided, you will witness fewer losses due to these inexcusable causes.

My experience and observations have shown that Purple Martins prefer enlarged compartments, no ands, ifs, or buts about it. The seclusion and protection offered by my Lakeview Series Houses is an unmatched asset that cannot be found in any other martin house design. They incorporate superior design practicality while incorporating North America’s deepest horizontal compartment (13+ inches inside the compartment). It should be no surprise to anyone that martins love my houses. All that is required is a desire on your part to discover this fact also! Many others already have and the wave of discovery continues. 

NOW THAT YOU HAVE READ THE FACTS, are you prepared to make the best decision for your overall success as a martin landlord?

Are you willing to address the potential problems that you may not have been aware of with your existing, conventionally designed martin houses?

Are you ready to enjoy growth in your colony that you have never been able to attain before?

Are you ready to increase your chances of success?

Make it a priority to include a Lakeview Series Purple Martin house in your plans! You will be making the best investment for yourself and for the martins.