Think twice about ordering chicks through the mail (the dire effects of shipping)

When I first decided to get backyard chickens, I learned I could have day-old chicks mailed to me from pretty much anywhere in the United States via the U.S. Postal Service. My first reaction… WTF!

Seriously? How could that possibly be a good idea?

And then I read what you’ve probably already heard.

Here are the claims for why mail-order chicks are supposedly no biggie:¹

1. Chicks won’t starve, dehydrate, or become malnourished. Chicks hatch with some of the yolk material from their egg still available for sustenance. This yolk sac is inside their bellies and will completely nourish them for 72 hours without food or water.

2. Chicks stay warm during shipping, no matter how cold it is outside. They huddle together in the shipping box and produce all the heat they need. (As an aside, small orders may ship with heat packets.)

3. Chicks don’t overheat, no matter how hot it is outside. Chicks love the heat!

4. The mortality rate doesn’t increase with shipping. The number of deaths from shipped chicks is comparable to non-shipped chicks.

No… No… No… And no.

I didn’t know at the time that these claims were all false, but, regardless, I didn’t order mail-order chicks anyway. Instead, I picked them up in person from a hatchery about an hour away. Why? Because something just didn’t sit right with me about having chicks shipped in the mail.

Even if the claims were true, I could not fathom how terrifying that experience must be for young chicks. Shoved in a box, jostled by transport vehicles and handlers and not understanding why, peeping in fear for days with no response from a caretaker, living in the dark, not being able to move around…

What a sad start to life!

Since then, I’ve learned it’s much worse than that. Because the golden claims the hatcheries make aren’t true. None of them. After reading dozens and dozens of scientific papers around this topic, I’ve found the truth is rather ugly.

The truth about shipping day-old chicks (This is your TLDR section!)

Here’s the truth in a nutshell:

Ugly truth #1

The yolk sac was never meant to be the sole source of food for a chick for 72 hours—it’s a complement to feed, not a substitute for feed.^2-5

Even when newly-hatched chicks are kept without feed and water in prime conditions (low stress, no shipping, optimal temperature and humidity levels), mortality rates and other health issues increase drastically by 72 hours.^6-8 Adverse effects have been found in both broilers and laying hens.

Some studies suggest 60 hours is the longest chicks can go in a stress-free environment without food and water before an increase in death rate or other serious problems occur.^6,8 Others show a rise in mortality by just 48 hours.⁷ (Please note, some of this mortality happens after the period of starvation, up to 6 weeks later. Effects of food deprivation are long-lasting indeed.)

Conversely, the research on shipped chicks shows that 60 hours is too long for chicks to go without food and water, and even 48 hours may be too long.^6,9-10

Ugly truth #2

The environmental conditions that are frequently encountered during shipping (heat, cold, too dry, too humid, transport movement, noise, etc.) cause immense stress on baby chicks.^6,10-15

Ugly truth #3

Mortality rates are higher (and sometimes significantly so) for shipped chicks than for non-shipped chicks.^6,9-10,13-15

This higher mortality in shipped chicks may occur during shipping, immediately after shipping, or weeks later.  

That’s the truth in a nutshell. Now, let’s get into the weeds!

The egg yolk sac: You need to know the basics

What is the egg yolk sac?

A couple of days before a chick hatches, its remaining yolk material becomes enclosed within the abdominal cavity as an extension of its intestine. This is the egg yolk sac.^16-18

The chick will continue to absorb this yolk material for energy over the last couple of days of incubation, during hatching, and in its first week or so of life.

The yolk sac is composed of water, proteins, and lipids, and comprises anywhere from 8%-20% of a chick’s total body weight at hatch.^5,12,18 This wide variation in percentages results from differences in breeds, strains, and even individuals, as well as in egg sizes, incubation temperatures, and likely other factors as well.^16,18

What is the egg yolk sac for?

In short, the egg yolk sac is a means to provide chicks with immediate nutrition.^7-8,16,19

This can be critically important for the chick’s survival during the first couple of days of life because the yolk allows it to survive without food or water for a limited time.¹⁶

In the natural world, newly hatched chicks can’t survive on their own. They rely on their mother for warmth, for protection from harm, and to teach them what’s appropriate to consume and what’s not.^20-23

Because eggs in a clutch hatch over an extended period of time, the chicks who hatch the earliest must have an internal source of nutrients so they don’t need to search for food and water right away by themselves.⁷ The egg yolk sac is that source, and it ensures the chicks can safely wait for their siblings to hatch before leaving the nest.

Additionally, chicks need to learn to eat in those first few days of life before their egg yolk sac is depleted.²⁴

Most people assume chicks automatically know how to consume all they need, but it’s much more complicated than that. Chicks have to learn to peck at tiny objects (like food) with accuracy, learn how to pick up objects and manipulate them with their mouths, and they have to learn how to swallow.^25-26 They even have to learn what food looks, smells, and tastes like.

As one study said about the first 72 hours of a chick’s life:

“…during this period, it is vital that the bird learns to feed, that is to apprehend food items with its beak and to distinguish between these and nonfood items.”

— Birte Nielsen et al., Poultry Science

Vital.

The yolk sac nutrients help assist chicks during this learning period.

Unfortunately, shipped chicks miss this learning period and have to learn how to eat after their yolk sac is already depleted. By this time, they tend to already be malnourished and dehydrated, and some are even on the edge of starvation.

How long does it take for the yolk sac to be absorbed?

The scientific literature will tell you that it takes up to ~5 days for the egg yolk sac to be absorbed.^16,18,27 That’s how long it takes for most chicks to starve to death when living on the egg yolk sac alone. Birds tend to starve to death on the 5th day. Yucky, I know. That’s research for you.

But surprisingly, even when chicks starve to death, some of the yolk sac still remains unabsorbed in the chicks’ abdomens. This finding goes back as far as 1929 when a scientist wrote:

“It is interesting to note that autopsies of the starved chicks which died revealed in many cases considerable quantities of unabsorbed yolk, suggesting that the yolk of itself is not sufficient to support life.”

— Sylvia Parker, Hilgardia

As you’ll learn below, modern research strongly supports this old hypothesis. But first, why do hatcheries and other online sources claim that the egg yolk sac only lasts for 3 days? Well, two reasons. The first is that by day 3, the yolk sac is mostly depleted.^8,14,28

The second is that many day-old chicks are several hours older (sometimes 1-2 days older) than the hatcheries claim.^29-30 So, when the hatcheries give themselves 72 hours to get chicks to you, in practice, some of those chicks are actually older than 72 hours. I know that probably sounds a bit confusing, but the next section will thoroughly explain.

Why your day-old chicks are likely older than the hatchery tells you

Hatcheries and the USPS tell you you’ll get your chicks within a 72-hour window. And that’s true much of the time, but it’s not as straightforward as it seems. You’re going to see that chicks are typically older than what you’re told.

Does that mean the hatcheries are lying to you? No. It just means they calculate the age in a strange way, a practical way that’s been the industry standard for…well, probably forever.

What is a day-old chick?

I used to think a day-old chick was a chick who was 1 day old. But then I saw feed stores selling the same “day-old chicks” day after day. I realized that, unless they have some kind of magical anti-aging secret, these chicks are not 1 day old.

A day-old chick is simply a chick that hasn’t been fed since hatching.¹⁰ So, when you get day-old chicks in the mail, they can be anywhere from 1 to 3 days old, or even older.

The feed stores that sell day-old chicks also tend to have day-old chicks shipped to them from hatcheries via USPS, same as you do. These stores obviously are feeding the chicks by the time they put them out for sale. But once fed, the day-old chicks are technically no longer day-old.

Why chicks hatched together are never the same age

Chicks incubated together don’t all hatch at the same time. Chicks incubate over a period of about 21 days, but they may hatch as early as 461 hours (~19 days, 5 hours) or as late as 510 hours (21 days, 6 hours).³¹

That’s a 49-hour spread! Two days! That spread is called the hatching window.

“[The hatching window is] the period of time elapsed from the hatching of the first chick to the hatching of the last chick.”

— H. Bergoug et al., World's Poultry Science Journal

The hatching window for any batch of chicks can vary widely, but most commercial hatcheries (think factory farms) have a hatching window between 24-48 hours.^30-32

Unfortunately, I could find no data for typical hatching windows for backyard chicken hatcheries. But the minimum hatching window I could find in the literature for commercial hatcheries was 12 hours.¹⁰

The hatching window falls on a bell curve, where the majority of chicks are hatched in the middle of the window.^6,30

The less uniform the eggs are, the longer the hatching window tends to be.³¹ So, if hatcheries incubate eggs together from different origins—different breeds, strains, or breeder flocks—they’re likely to have a longer hatching window.

Similarly, if the eggs are different sizes or have been stored in different conditions or for different durations of time, a long hatching window may result.³² Even variability in the incubator (such as a temperature gradient) can lengthen the hatching window.

Uniform eggs from the same source, then, should have the narrowest hatching windows.

Why day-old hatchery ages aren’t accurate and why it matters

When you think of the age of a chick, you’re likely thinking of the biological age, which refers to the time the chick hatched from the egg.^30,32 Chicks who are incubated in the same batch hatch over a period of 12-48 hours, and therefore will have different biological ages.

But when the hatchery tells you an age for your chicks, they most often give you the chronological age, which refers to the time the chicks were removed from the incubator after the hatching window has closed. ^30,32

“In practice, all chicks stay in the incubator until almost all have hatched.”

— H. Willemsen et al., World’s Poultry Science Journal

Chicks that are incubated in the same batch will have the same chronological age if they are removed from the incubator at the same time.

Can you see how this is a problem?

Chicks in a batch could have biological ages anywhere from 12 hours to 2 days apart, but they will have the same chronological age.

So, if you get chicks in the mail who are 72 hours old (chronological age), some of those chicks may actually be 84 hours old or even 120 hours old (biological age). This means those supposed 3-day-old chicks are actually 3.5 days old or 5 days old, respectively. And some (or all) of them may be dead.

And even if you get your chicks when they’re just 48 hours old (chronological age), some may already be on the edge of starvation, especially when you take into account the depleting effects of shipping. (More on that below.)

The myth of the all-nourishing egg yolk sac

Why the egg yolk sac isn’t enough to sustain chicks

I’ve said it before and I’ll say it again. For the most part, the egg yolk sac isn’t a substitute for food; it’s a complement to food.^2-5 It’s not meant to replace food and water. It’s meant to be used alongside it.

The only time the egg yolk sac should be considered as a substitute for food and water is during the hatching and recovery period. The yolk sac does sustain chicks while they recover from hatching and while they wait for their siblings to also hatch and recover.⁷

Following hatching and recovery, the egg yolk sac both provides necessary nutrients for fast growth and assists chicks for the next few days as they gradually transition to full sustenance on exogenous food and water.^7,19,33

But during those first 3 days of life, the egg yolk sac only contributes ~10-30% of the total energy and protein intake of a chick. The exact amount depends on how much food and water they’re consuming.¹⁹

The yolk sac is also depleted rapidly in this short time span. Chicks from laying breeds absorb ~40% of the yolk sac within the first 24 hours, ~60% within 48 hours, and ~80% within 72 hours.³⁴

Broiler chicks, on the other hand, absorb ~45-55% in the first 24 hours, ~65-70% within 48 hours, and ~80% within 72 hours.^8,34 So, broilers have slightly better utilization of the egg yolk sac than laying hens in the first 2 days of life, but laying hens catch up to them by day 3.

Although somewhat controversial,^7,18 several studies imply that when chicks are allowed to feed, they absorb the egg yolk sac more rapidly than chicks who are deprived of food.^5,16,35-37 This is possibly due to the greater intestinal activity of fed chicks (causing absorption of the yolk more quickly into the intestines), and has been documented in both broilers and laying hens.

Think about that for a minute. The chicks who have access to food and water within 6-24 hours after hatching will also access the yolk sac nutrients more quickly. It’s like a little “nutrient boost” early on, including earlier absorption of important minerals, amino acids, protein, and lipids. ^5,36

On the other hand, food-deprived chicks (like shipped chicks), who are forced to live on their egg yolk sacs for considerably longer, don’t get this earlier “nutrient boost.”

Instead, food-deprived chicks lose significant weight since hatching by the time they’re just 48 hours old.^29,38 And they weigh considerably less than fed chicks of the same age.²⁹ This concerning weight loss is evident across all different breeds, regardless of whether they are broilers, layers, or dual-purpose birds.^24,34,39

It’s quite astounding with facts like these that people are still claiming chicks get everything they need from their egg yolk sac alone!

The research also suggests that newly-hatched chicks who are fed early have other wide-ranging advantages over food-deprived chicks.

These include:

• Increased body weights^30,36-37
• Earlier development of major organs, including the liver, pancreas, spleen, and heart^5,7,36,39
• Better immune system development, including better responses to infectious diseases encountered later in life^5,7
• Faster and/or more efficient use of glucose³⁰
• Earlier development of the gastrointestinal tract^{7,32,37,40-42}

When newly-hatched chicks are deprived of food, some of their organ development is delayed.⁷ Thankfully, though, most of these chicks do eventually catch up when they’re finally allowed to eat.

However, the delay in the development of the digestive system may have long-lasting negative effects, reducing the digestibility and absorption of nutrients later in life.⁷

Why newly-hatched chicks need food a.s.a.p.

A newly-hatched chick’s digestive tract needs to undergo drastic changes in physiology and morphology to be capable of proper digestion and nutrient absorption.^{7,28,30,37,42}

Early feed, therefore, isn’t just for immediate nutritive purposes—it’s also for the stimulatory effect it has on getting the gastrointestinal tract moving.^19,30 Feeding stimulates secretions, growth factors, and neuronal factors that cause the gastrointestinal tract to grow and develop.

By the time the egg yolk sac has been depleted around 3 days of age, chicks who have already eaten plenty of food are more capable of digesting their exogenous protein- and carbohydrate-rich feed.²⁸ This means they are now much more capable of extracting the nutrients from this feed.

On the other hand, chicks who have been deprived of feed in their first days of life (as shipped chicks are) aren’t able to absorb nutrients as well when they do start feeding. This is because they need to feed for a while before their digestive systems can develop enough to absorb nutrients efficiently.

“Therefore, post-hatch feeding is critical for the development of the intestines and may affect the digestibility and absorption of nutrients later in life.”

— Ingrid de Jong et al., PLoS ONE

Do you see the problem here? Shipped chicks, who tend to be malnourished, dehydrated, and frequently starving by the time you get them, need food a.s.a.p. However, when they do finally eat, they can’t absorb the nutrients very well yet because their digestive systems are so immature. It’s a double whammy.

Additionally, as explained in detail earlier, because shipped chicks have spent their first few days of life in a hatchery and a shipping box, they still have not even learned yet how to properly eat.^24-25 So, it’s more like a triple whammy.

And on top of that, very weak chicks, such as those who have been shipped during high temperatures, will frequently show no interest in eating when they do finally get the chance.⁴³ A quadruple whammy?

Catastrophic deaths of mail-order chicks

How are mail-order chicks shipped?

Chicks shipped by the U.S. Postal Service are shipped by both truck and airplane.¹

First, they’re packaged up in special boxes by the hatchery. You can see what some of these boxes look like and learn about their special features in the video below:

After packaging, the chicks are typically driven to the post office or a nearby airport, then flown to an airport closer to the customer’s home.¹ There, they are driven from that airport to a post office near the customer’s home. The customer then picks the chicks up from the post office and drives them home.

It’s quite the journey!

The risk for mass deaths during and after shipping

“By the time mail-order chicks arrive at the local post office branch where their new owners will pick them up, [USPS spokesperson, Sue] Brennan estimates that five different postal employees have helped the chicks get there, from pilots to delivery drivers to dock dispatchers.”

— Winona Dimeo-Ediger, Country Living

And, sadly, a lot can go wrong during all these different branches of the shipped chicks’ journeys, sometimes catastrophically wrong.

For example, mass deaths have occurred from:

Starvation and dehydration, which become a huge risk with mail delays. During the pandemic of 2020, mail delays resulted in mass deaths for countless mail-order chicks, including 4,800 chicks delivered to the state of Maine alone.^44-45

Exposure to rain, wind, or snow, particularly if the chicks are left too long on loading docks or in other unsafe outdoor areas. NW Airlines once had 300 mail-order chicks die when their shipping boxes were exposed to rain during a layover.⁴⁶

“Airline employees made ‘valiant efforts’ to save the birds, using blankets and lamps, says Kurt Ebenhoch, a Northwest spokesman. ‘It’s very upsetting,’ he says, adding that many Northwest employees are pet owners.”

— Devon Spurgeon and Stephen Power, The Wall Street Journal

Suffocation, such as when too many chicks are packed into a small space, like an airplane cargo hold. NW Airlines once had 9,000 turkey chicks die at one time from suffocation this way.⁴⁷

Exposure to hot or cold temperatures. Air Canada once lost 2,000 turkey chicks to heat stress when one of the planes the chicks were on sat in 108-degree weather at an airport in Las Vegas, NV. ⁴⁷

The catastrophic examples shared above aren’t the norm, but they do happen and they are a risk.

But what about the risks involved with the average shipped chick?

Shipping will always have additional risks for chicks. Let’s look at the most common ones.

The dire effects of shipping on the average mail-order chick

Malnourishment and starvation increase mortality rates

You already learned above that the egg yolk sac alone doesn’t provide newly-hatched chicks with all the nutrients they need.^2-5

Even when kept in optimal environmental conditions (without shipping), chicks lose a significant amount of weight within their first 48 hours if they’re not fed.^{24,29,34,38-39} On the other hand, fed chicks will actually gain weight during this period.

As one study puts it:

“Chicks that lose weight are presumably not eating and are in a state of starvation.”

— G. Santos and F. Silversides, Poultry Science

The hatcheries tell you that chicks can go 72 hours without food and water with no negative effects whatsoever, but research indicates this view is outdated.^6-8 At best, chicks can go 60 hours without an increase in mortality rate, but only if they’re kept in optimal conditions. That means they’re kept in a low-stress environment in ideal temperatures and humidities.

And one particularly interesting study performed a meta-analysis on about 50 recent peer-reviewed papers about the effects of depriving newly-hatched broiler chicks of food and water.⁷ The meta-analysis found that, even in optimal conditions, chicks who did not get food in their first 48 hours of life experienced an increased risk of mortality that lingered up to 6 weeks of age (i.e., their slaughter age). Again, this is for non-shipped chicks raised in optimal conditions.

What’s particularly interesting about that meta-analysis is that the higher mortality at 48 hours wasn’t evident in most of the individual studies, but was obvious in the meta-analysis of the combined data. Unfortunately, I could not find any meta-analyses on laying hen data, but the research is clear at least that deleterious effects are evident beyond 60 hours of fasting in layers too (in otherwise optimal conditions).⁶

Conversely, the research on shipped chicks shows that 60 hours is too long for chicks to go without food and water, and even 48 hours may be too long.^6,9-10

Many of the studies on shipped chicks document the potential for high mortality during transit, immediately after transit, and/or even weeks later.^6,9-10,13-15

Suboptimal shipping temperatures increase mortality rates

Hatcheries that sell backyard chickens may tell you that adverse ambient temperatures don’t increase the risk of mortality in shipped chicks.¹ However, hatcheries that serve factory farms will tell you otherwise. They are well aware of just how important temperature is and that’s why they ship their chicks in climate-controlled trucks.^11,15,48

Studies have found that chicks fare best in trucks that are kept at an ambient temperature of 75-79°F (24-26°C) and relative humidity of around 75%.¹¹ These conditions help ensure that the temperature inside of the shipping boxes stays around 86-90°F (30-32°C), which results in the chicks’ maintaining a healthy body temperature of 103-105°F (39-41°C).^14,49 However, some sources recommend the in-box temperature be a bit higher at 90-95°F (32-35°C).⁵⁰

In reality, the number of chicks per box, the amount of ventilation in the vehicle, and many other factors can modify these numbers a bit.⁵¹

Even when chicks are transported this way in these climate-controlled trucks, mortality in the first week of life is higher than for chicks who haven’t been shipped at all.¹⁵

Unfortunately for backyard chicken keepers, the USPS doesn’t ship chicks in climate-controlled trucks or planes. The mortality risk for mail-order chicks is greatly exacerbated by adverse temperatures during travel.^13-14,43

How temperatures that are too high contribute to mortality

When the ambient temperature is too high, chicks use more energy to try to stay cool. This results in more rapid weight loss and an increased risk of death.^38,43,51

How high is too high? According to one study, chicks can start dying after just 3 hours of transport when the ambient temperature is 100° (38°C) and relative humidity is 75%.¹³

In another study, newly-hatched chicks weren’t transported, but were held in holding cells for 72 hours at an ambient temperature of 97°F (36°C). Mortality was more than 50% higher than it was for controls held at a temperature of 86°F (30°C).¹⁴

In another study, chicks who were kept at an ambient temperature of 102°F (39°C) for 48 hours lost more than 20% of their body weight.⁴³ By the end of the 48 hours, they were incredibly weak and did not have any interest in eating or drinking. Many of them died within the week. (And these chicks weren’t even shipped.)

The above studies were performed on broilers, who do tend to produce more metabolic heat than layer breeds, so these numbers may change slightly for other backyard birds.

But just think about how hot conditions can get during the warmer months of the year. Chicks shipped by the USPS will have to withstand these temperatures, while also being exposed to all the other stresses of shipping.

Additionally, if the humidity is high, the problems of heat are exacerbated. In general, the more humid the air, the harder it will be for the chicks to stay cool.¹⁵

How temperatures that are too low contribute to mortality

Newly-hatched chicks have a difficult time maintaining their body temperature when exposed to low temperatures.⁵² They’re likely to be even less capable when deprived of food (as shipped chicks are).^30,53

A single newly-hatched chick can become hypothermic when exposed to an ambient temperature of 66°F (19°C) for just 15 minutes.⁵² Under conditions of simulated transportation, a group of 100 chicks in a shipping box can become hypothermic when exposed to an ambient temperature of 68°F (20°C) for just 3 hours.¹³

Thankfully, none of the hypothermic chicks died in the two studies above, but the results are still concerning as day-old chicks shipped via USPS are frequently exposed to much lower temperatures and for much longer periods of time.

Perhaps more concerning still, another study found that when newly-hatched chicks were held at an ambient temperature of 75°F (24°C) for 48 hours, some of the chicks stopped absorbing their yolk sacs altogether.¹⁴

Think about that. Cold chicks need to use energy to maintain their body temperature. They haven’t been fed, so they have no energy to use from food. That means the only spare nutrients they have access to are in their egg yolk sacs, but the cold may prevent them from accessing even those.

Additionally, chicks who were held at an ambient temperature of 75°F (24°C) for 72 hours had a mortality rate almost 3 times as high as controls who were held at warmer temperatures.¹⁴ And these chicks weren’t even shipped, so they didn’t have exposure to any other stresses.

Now just imagine how cold the ambient temperature can get for chicks shipped via USPS, particularly if ordered during a colder time of the year. Yes, the temperature in their shipping box will be higher than the ambient temperature due to the chicks’ body heat, but you’re always taking a huge risk when you have your chicks shipped in the cold.

How the low humidity conditions on airplanes contribute to mortality

You’ve learned that high humidity can prevent chicks from being able to cool down in the heat, but low humidity can have its problems too.

Something really awful happens in the cargo hold of an airplane when cruising altitudes (10-12,000m) are reached. As one study explains it:

“…when the flight altitude is reached, there is a special situation with regard to the relative humidity, which is generally little known and is therefore insufficiently taken into account.

At flight altitude (10,000 to 12,000 m) the air temperature is about -50°C and the relative humidity below 40%. If this air is compressed to the required cabin pressure, on the one hand heat is released… and on the other hand there is an extreme drop in relative humidity to below 0.5%. While the supply air heats up almost instantly to values of around 25°C due to mixing with the cabin air, the relative humidity in the cargo hold only reaches values between 10% and 15%.”

G. Schlenker and W. Müller, Berliner und Münchener tierärztliche Wochenschrift

In short, at cruising altitudes, the relative humidity (RH) in the cargo hold drops to uncomfortably low values, resulting in extreme dryness. Why is this important?

As another study puts it, “Such low RH would undoubtedly accelerate dehydration and body mass loss of the chicks.”⁹ This study (with some very high mortality rates) measured relative humidity at ~19% in the airplane cargo hold where their shipped chicks were held.

This means that at the humidity conditions found in airplane cargo holds, shipped chicks can face a huge risk of moderate to severe dehydration.¹⁰ Chicks may exhaust the water supply in their egg yolk sacs within 48 hours just from breathing alone! That doesn’t even take into account the water they inevitably lose from their skin and their excrement.

And if that’s not enough, there are other variables that also can accelerate a chick’s dehydration on top of that. Heat stress is one of them.³⁸ Time spent in the incubator is another.⁴³ Early-hatched chicks may spend a long time in hot and humid incubator conditions while waiting for the rest of the chicks to hatch, causing dehydration long before shipping even commences.

Why the USPS refuses to ship chicks as live animals and what that means for mail-order chicks

You’ve learned that the majority of shipped chicks are shipped via both airplanes and trucks. You’ve learned that chicks are shipped in cargo holds of airplanes where they are subject to temperature extremes and dangerously low humidity levels at cruising altitude.

Is it any surprise, then, that the data shows mortality can be especially high during flights and for at least a week following flights?

In fact, the mortalities from air transport are so high, Northwest Airlines did declare back in 2001 that they would no longer ship day-old chicks as U.S. mail.^46,54 The airline estimated about 30% of day-old chicks died during flight transit, and, though not common, sometimes as many as 60-80% of chicks would die on a single flight.

And those numbers are dead-on-arrival. They don't even include the deaths that commonly occur in the week or more after flights.

I suspect the estimate of 30% is high but shipped chick deaths do appear to be a lot more common than the hatcheries would like you to think.

This is partly due to the fact that chicks shipped via USPS are typically held in the cargo hold of the airplane like baggage and given no special treatment (they are shipped as mail, after all).⁴⁶

One study of long airplane flights revealed that when chicks were delivered to their final destination at 72 hours old (which includes the time spent at the hatchery and all transport times), 11% were dead-on-arrival, and almost 50% died within 7 days.⁹ This same study showed that even chicks who were delivered within 48 hours of hatch could have a high mortality rate of 2% dead-on-arrival and 18% dead within 7 days.

The flights in that study were particularly long, ranging from 13 to 18 hours of flying time. Flights within the U.S. are typically shorter than that (when you exclude ground times and layovers). This means that for most backyard chicks shipped in the U.S., mortality rates should be lower than the estimates given above, but clearly, transport in airplane cargo holds is risky.

Northwest Airlines knows just how risky it is because they see many of these deaths firsthand.

And that’s why they wanted to change their shipping rules.⁴⁶ They refused to ship day-old chicks any longer as U.S. mail and stated baby chicks must be shipped as live animal cargo (like your dog or cat would be). That way, the chicks would get the special care they required to better survive air travel.

“The airline also wanted the right to refuse any animal shipment ‘that in the sole opinion of the carrier cannot be transported in a safe and humane manner,’ according to a Northwest memorandum.”

— Devon Spurgeon and Stephen Power, The Wall Street Journal

Sounds reasonable, right? But the government stepped in the way.

U.S. hatcheries, led by the Murray McMurray Hatchery of Iowa, lobbied the U.S. government to force the airlines to continue shipping chicks as mail.⁴⁶ They didn’t want to have to pay the higher price for chicks to be shipped in safer conditions as live animals.

Sadly, Northwest Airlines lost this battle. Congress passed a bill that stated that the USPS could raise the rates a little bit if they wanted to help airlines, but the rates would still be kept well below those charged for live animal cargo. Thus, mail-order chicks are still shipped as U.S. mail in cargo holds.

But it really doesn’t have to be this way. Some countries outside of the U.S. ship chicks in a much more humane way. The Germans are a good example.

Back in the 1970s, records of border veterinary examinations at Frankfurt Airport found about 13% of shipped chicks were found dead-on-arrival.¹⁰ Great efforts were then taken by the airlines to reduce this high mortality rate. Today, Lufthansa Airlines ships day-old chicks in climatic chambers during the flights, protecting them from extremes of temperature and humidity.⁵⁵

You can see how nice this setup is below in Lufthansa’s Animal Lounge:

But the U.S. isn’t there yet. And our chicks pay the price.

Other factors that potentially harm shipped chicks

Aside from problems with malnourishment, starvation, dehydration, overheating, and overcooling, there are many other factors that adversely affect chicks. Almost everything about the shipping process is stressful for them.

Additional stressors may include:

• Altered atmosphere on roads¹²
• Crowding¹⁰
• Fear¹⁰
• Hatchery processing like sorting, sexing, debeaking, vaccinations, packaging^31,48,56
• Lack of response from a caretaker
• Lack of sleep from transport
• Long periods of darkness¹⁰
• Noises³¹
• Poor ventilation³¹
• Restriction of natural behaviors¹²
• Rough handling before or during transport (or really any handling)³¹
• Social disruption¹²
• Unexpected accelerations¹²
• Vibration from transport vehicles³¹

What’s the solution to mortality problems for mail-order chicks?

The obvious solution is to never order mail-order chicks. Just pick them straight up from your nearest reputable hatchery or breeder instead. Alternatively, you could learn how to hatch them at home (although there is a learning curve for that). Or go the natural route: once you have an established flock, you can let your mama hens hatch them!

But if you do decide you want to have chicks shipped to you, consider ordering your mail-order chicks from a hatchery near you, rather than one from across the country.

First, contact the hatchery to see where they ship from. Some hatcheries you find online are middlemen, meaning they don’t hatch the birds themselves. The birds may actually ship from several states away from the company’s location.

But are there any other ways we can improve our chicks’ shipping experiences?

This might sound crazy at first, but factory farms are actually at the forefront of finding solutions to some of these problems of shipping chicks. It makes sense when you realize that factory farms aren’t in denial about the increased losses they incur from shipping chicks. These losses lower their profits significantly, so it’s in their best interest to find solutions.

Adopting some of the practices factory farmers are testing out may be beneficial for shipping backyard chickens as well.  

Possible solutions include:

Shortening the duration of shipping. This would mean hatcheries would no longer ship nationwide but would only ship to customers within a closer range so transport time for chicks is much shorter.

Shortening the hatching window. A shorter window means the earliest hatched chicks don’t have to be held in the incubator for so long. Hatcheries could stop hatching birds from different breeds and strains in the same incubator to shorten the hatching window. The more similar the eggs are (e.g., genetics, size, etc.) and the more similar their transport and storage conditions have been, the shorter the hatching window.

Removing earlier-hatched chicks. Hatcheries could remove and ship the earlier-hatched chicks before later-hatched chicks. This would reduce the amount of time they’re forced to live off their egg yolk sacs.³⁰

Shipping chicks in climate-controlled trucks and airplane cargo chambers.^11,15,48,55

Providing food and water to chicks in the egg before hatching with in ovo feeding.^28,30,42

Providing food and water at the time of hatch, during holding before shipping, and during shipping itself.^30,32,48 Some factory farm trucks will actually stop during transport to provide light and water/nutrient gels to chicks mid-journey.^57-58

Lastly, supporting hatcheries when they commit to making changes. Most of these changes will cost the hatcheries money, and they will likely need to pass that on to the consumer to stay in business. I think one of the best things we can do right now is applaud any hatchery who attempts to make an improvement, and happily pay the higher prices. When we don’t pay the price, our animals pay the price.

Unfortunately, some of the solutions above have had mixed results. For example, some studies found that feeding chickens nutritional gels before shipping provided long-term health benefits, but other studies didn’t find any correlation.^8,30

And although the majority of research studies do advocate for feeding chickens soon after hatch, one breeding company claims that for especially long journeys, mortality can actually increase if chicks are fed at hatch and then not fed again during transit.¹⁴

They argue that because food gets the digestive system to start growing and developing, a period of starvation after eating could cause stomach acid and enzymes to damage the gut. Best just to let the chicks try to survive on their egg yolk sacs, even though we know that the egg yolk doesn’t give them all the nutrition they need.

Unfortunately, there’s still a lot to learn and a lot more research to be done.

What can you expect when you order shipped chicks?

If, after learning all this, you still decide you want to have mail-order chicks shipped to you, you can take some comfort in knowing that the majority of shipped chicks do survive. The hatcheries would go out of business if they didn’t.

You should also know that most deaths tend to be concentrated, not randomly distributed.^10,46,59 So, if you do have losses, you may have significant losses.

This makes sense when you consider that some shipments will inevitably experience considerably worse conditions than others. Those shipments can be expected to have high losses.

But even boxes shipped within the same truck or plane may have considerably different mortality rates, as different parts of the vehicles have different microclimates.^15,50,59

For example, a box that’s shipped in the middle of a truck and surrounded by other packages may experience more warmth and less airflow than a box that’s near the door. If the ambient temperature in the truck is too high, the chicks in the middle of the truck may get too hot and die. If the ambient temperature in the truck is too low, the chicks near the door may get too cold and die.

Additionally, if you just happen to end up with chicks who hatched earlier during the hatching window, well, those chicks are older and have therefore been deprived of food for longer. A higher mortality could result from that as well.

It all just feels like a bit of a gamble, really.

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