How do Bees Breathe?
Many people assume bees breathe in the same way we humans do, using lungs to pull in oxygen. However, bees don’t breathe in this way at all. Instead, they have a remarkable respiratory system made up of tiny openings called spiracles and a network of air-filled tubes that deliver oxygen directly to their tissues. Here’s how the bee respiratory system works and why it is so different from our own.
Don’t worry, you don’t have to be an entomologist to enjoy a little bee biology. Even beekeepers benefit from understanding the basic parts of a bee and how they all work together.
Do Bees Have Lungs?
No, bees do not have lungs. They rely on a specialized respiratory system that delivers oxygen directly to their tissues.
Air enters through tiny openings along the bee’s body. These openings connect to a network of tubes called tracheae.
Tracheae carry oxygen throughout the bee’s body and removes carbon dioxide.
So, while bees don’t have lungs, they do have an impressive, highly efficient respiratory system that is perfectly suited to their needs.
How Bees Breathe
The respiratory system of honey bees consists primarily of spiracles, tracheal tubes, tracheoles and air sacs.
Together, these structures move oxygen throughout the body and remove carbon dioxide waste.
In a sense, it’s still “good air in and bad air out”—just accomplished in a very different way than humans and other mammals.
Bees do not use lungs to inflate and deflate with each breath. Instead, oxygen travels through a network of air-filled tubes that reach deep into the body.
These tubes branch repeatedly until they reach individual tissues and cells. As cells use oxygen to produce energy, carbon dioxide is created as a waste product.
The bee’s respiratory system carries this waste gas back through the tubes and out of the body through the spiracles.
This direct method of oxygen delivery is one reason the bee respiratory system is so efficient.
The Role of Spiracles
You have likely never noticed the spiracles on a bee. They are tiny.
Air enters the body through these valve-like openings in the exoskeleton called spiracles. They openings appear along the sides of the body, and most insects have 10 pairs.
In honey bees, the first 3 pairs are located on the thorax and the remaining 7 pairs are found on the abdomen.
If you look closely at bee larvae, those little dark dots on the sides are the developing spiracles.
Spiracles play a major role in how honey bees breathe. These tiny openings can open and close as needed to regulate airflow.
When a bee is active and requires more oxygen, the spiracles open wider. During periods of rest, they can remain partially closed.
This helps regulate gas exchange while reducing moisture loss from the body.
Why Bees Don’t Breathe Through Their Skin
No, bees do not breathe through their skin. But some animals, such as earthworms, can exchange gases through their skin.
Bees are different because they are covered by a hard exoskeleton that protects the body and helps prevent moisture loss.
Instead, bees rely on their spiracles and tracheal system to move oxygen throughout the body and remove carbon dioxide waste.
Breathing During Flight
Bees are able to fly quite well. But it requires a tremendous amount of energy, and that means a bee needs more oxygen.
When bees are traveling long distances in search of nectar and pollen or if they are defending the colony from intruders, their muscles require a constant supply of oxygen-rich air.
During periods of intense activity, muscles in the abdomen help increase airflow through the respiratory system. The air sacs expand and contract more rapidly to move oxygen where it is needed.
If you see a bee rapidly pumping her abdomen, she is often working to increase oxygen delivery to her tissues.
I have often see this happen when I would save a dying bee from drowning. This movement may be subtle under normal conditions but becomes much more noticeable when oxygen demands are high.
Factors Affecting Bee Respiration
Activity level is one factor that affects how much oxygen a bee needs. However, environmental conditions and colony health can also influence respiration.
Others include:
- temperature & humidity
- pest/disease
Bees are cold blooded insects that are sensitive to temperature changes. Cold temperatures cause their bodies to slow down – it becomes harder for them to breathe or move.
In very hot weather, they flap their wings (called fanning) to cool the hive. This extra ventilation can result in a loss of moisture which makes breathing more difficult.
Humidity is a tricky thing for a bee colony. Too much humidity can be a serious problem for a colony – especially in the winter beehive.
Likewise, the respiratory health of honey bees may be damaged by pests of honey bee diseases:
- mites (tracheal mites and varroa mites)
- fungal infections
- bee viruses
FAQs
Bees do breathe oxygen but can survive a short time without it. They can close their spiracles to protect themselves from drowning but carbon dioxide continues to build up inside their body.
Yes, air enters the bee through spiracles and travels along the tracheal tubes into the tracheoles. Here gas exchange takes place with oxygen moving in and carbon dioxide moving out of the cells and into the tubes to be expelled from the body.
Seeing a honey bee rapidly pumping its abdomen means it needs more oxygen. Muscles in the abdomen pump to change the pressure in internal air sacs and get oxygen to where it is needed.
Bees do not breath in and out through their mouth or nostrils. They have openings on their body called spiracles that allow air to enter and leave the body.
Bees do not have lungs but the air sacs located inside the tracheal tubes help get oxygen rich air to where it is needed. Once there, tiny tracheoles create the gas exchange within the cells.
Finally
So, now you know – honey bees do not have lungs. But, they do have an interesting respiration systems that works well to get oxygen-rich air to every cell in their body. In some ways, that is the same thing that lungs do for us – just a different way to get it done.
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