Axolotls have one of the most unusual respiratory systems in the animal kingdom. Unlike most creatures that rely on just one breathing method, axolotls use three different ways to get oxygen. This remarkable ability makes them perfectly adapted to their aquatic lifestyle and plays a role in their famous regeneration powers.

The Quick Answer

Axolotls breathe through three methods: external gills, lungs, and skin absorption. Their feathery external gills are the primary breathing tool, extracting oxygen directly from water. They also have functional lungs and occasionally swim to the surface for air gulps. Additionally, their skin absorbs oxygen from surrounding water. This triple breathing system gives axolotls incredible flexibility in different water conditions.

Method 1: External Gills (Primary Breathing)

What Those Feathery Things Are

The most noticeable feature on any axolotl is the crown of feathery branches sticking out from both sides of their head. These are external gills the main way axolotls breathe underwater.

Gill structure:

• Three branches on each side (six total)
• Each branch covered in tiny filaments
• Bright red or pink color from blood vessels
• Constantly moving and waving in the water

Unlike fish gills hidden inside gill covers, axolotl gills remain exposed throughout their entire lives. This is part of their neoteny keeping juvenile features as adults.

How Gill Breathing Works

The process is surprisingly simple and efficient:

Water flows over the gills either from the axolotl swimming or from water currents in their environment. The gills wave gently, maximizing contact with fresh water.

Oxygen diffuses into blood vessels running through each gill filament. The massive surface area created by all those tiny branches allows rapid oxygen absorption.

Carbon dioxide diffuses out at the same time. The gills work in both directions taking in oxygen while releasing waste gas.

Blood circulates through the body, delivering oxygen to tissues and organs. The heart pumps oxygenated blood from the gills throughout the axolotl’s system.

This method works so well that healthy axolotls in oxygen-rich water can meet all their breathing needs through gills alone.

Reading Gill Health

Gill appearance tells you a lot about an axolotl’s health and water quality:

Fluffy, fully extended gills indicate excellent health and good water quality. The filaments fan out, creating maximum surface area.

Curled or shortened gills suggest poor water quality, low oxygen levels, or stress. The gills contract to protect themselves from irritants.

Pale or white gills signal reduced blood flow or anemia. Healthy gills should be pink to deep red.

Damaged or missing gill filaments result from poor water quality, fighting, or disease. Fortunately, gills can regenerate if conditions improve.

Forward-curved gills often mean the axolotl is moving or actively swimming. This is normal temporary positioning.

Method 2: Lung Breathing (Backup System)

Yes, Axolotls Have Lungs

This surprises many people, but axolotls possess functional lungs despite spending their entire lives underwater. These lungs develop early in larval stage and remain present throughout life.

Lung characteristics:

• Two lung sacs inside the body cavity
• Relatively simple structure compared to mammal lungs
• Not as efficient as gills for oxygen extraction
• Serve as a backup breathing method

The lungs sit in the body cavity, one on each side, and connect to the throat through a simple opening called a glottis.

How Lung Breathing Works

When an axolotl uses its lungs, the process looks like this:

Swimming to the surface happens when the axolotl needs supplemental oxygen or wants to adjust buoyancy. They rise smoothly through the water.

Opening the mouth at the surface allows air to enter. You’ll see the axolotl’s mouth break the water surface.

Gulping air fills the lungs. The throat expands noticeably as air rushes in. This happens in a quick motion gulp and down.

Descending back down follows immediately. The axolotl rarely stays at the surface more than a second or two.

Oxygen absorption from the air in the lungs happens over time as the axolotl goes about normal activities. Air can stay in the lungs for extended periods.

When They Use Lungs

Axolotls don’t rely on lungs constantly. They typically use them in specific situations:

Low oxygen water forces more frequent surface trips. If gills can’t extract enough oxygen, lungs supplement.

Warm water contains less dissolved oxygen than cold water. Summer temperature spikes increase surface breathing.

After exercise or stress leaves them needing extra oxygen quickly. Lungs provide a rapid oxygen boost.

Buoyancy control is an unexpected lung function. Air in the lungs helps axolotls float or maintain position in the water column.

Normal behavior includes occasional surface trips even in perfect conditions. Once or twice an hour is completely normal.

Surface Breathing Frequency

How often an axolotl surfaces varies dramatically:

Ideal conditions: Every 1-3 hours or less Moderate conditions: Every 30-60 minutes
Poor conditions: Every 5-15 minutes (this is a red flag) Extremely poor conditions: Constantly at surface (emergency situation)

If your axolotl suddenly starts surface breathing much more frequently, test your water immediately. Something is likely wrong with oxygen levels or water quality.

Method 3: Cutaneous Respiration (Skin Breathing)

Breathing Through Skin

The least obvious breathing method is also the most constant. Axolotls absorb oxygen directly through their skin 24/7.

How skin breathing works:

The entire body surface acts as a breathing organ. Oxygen dissolved in water passes through the thin, permeable skin directly into blood vessels underneath.

Slime coat covering the skin helps regulate what passes through. This protective layer allows oxygen in while keeping harmful substances out (when it’s functioning properly).

Blood vessels sitting close to the skin surface pick up absorbed oxygen and carry it throughout the body.

Carbon dioxide exits through the skin simultaneously, creating a constant two-way gas exchange.

How Much Skin Contributes

Scientists estimate that skin breathing provides:

• 10-30% of total oxygen needs in healthy adult axolotls
• Higher percentages in young, small axolotls with more surface area relative to body volume
• Increased contribution when gills are damaged or lungs aren’t used frequently

While skin breathing alone can’t sustain an axolotl, it provides meaningful supplemental oxygen constantly.

Why Skin Breathing Matters

This method explains several axolotl care requirements:

Temperature sensitivity partly relates to skin breathing. Cold water holds more dissolved oxygen that can be absorbed through skin. Warm water has less available oxygen.

Water flow helps by constantly bringing fresh, oxygenated water in contact with the skin. Stagnant water reduces skin breathing efficiency.

Clean water is critical because the permeable skin that allows oxygen in also allows toxins in. Ammonia, nitrites, and other pollutants enter directly through the skin.

Handling damages the slime coat, interfering with skin breathing temporarily. This is another reason to minimize handling.

Comparing the Three Methods

Efficiency Rankings

Each breathing method contributes differently to total oxygen intake:

External gills: 60-80% of oxygen in healthy axolotls with good water quality. This is the workhorse breathing method.

Skin absorption: 10-30% provides constant background oxygen supplementation throughout the day.

Lungs: 5-15% under normal conditions, but can spike to 30-40% if water oxygen drops or temperature rises.

These percentages shift based on conditions. In poor water quality, lung use increases dramatically while gill efficiency drops.

Backup Systems Save Lives

The three-method system provides incredible resilience:

If gills are damaged, lungs and skin pick up the slack. Many axolotls survive gill injuries that would kill fish.

If surface access is blocked temporarily, gills and skin continue working. This gives axolotls time to find alternative air sources.

If water oxygen drops, the combination of all three methods working at maximum capacity can sustain life longer than single-method breathers.

This redundancy is part of why axolotls are relatively hardy pets despite their specific care requirements.

How Breathing Changes Over Time

Baby Axolotls

Newly hatched larvae rely almost entirely on skin breathing initially. Their tiny gills are just developing, and lungs aren’t functional yet.

Week 1: Primarily skin breathing with developing gills Week 2-3: Gills become primary breathing organs Week 4+: All three systems fully functional

Adults

Mature axolotls establish a breathing pattern based on their environment:

Stable, cool water: Mostly gill breathing with occasional skin contribution and rare surface trips

Variable conditions: Flexible switching between methods as needed

Poor conditions: Heavy reliance on all three methods simultaneously, with frequent surface breathing

Senior Axolotls

Older axolotls (10+ years) sometimes show changes in breathing patterns:

• Gills may become less fluffy or slightly smaller
• More frequent surface breathing becomes normal
• Skin breathing remains relatively constant
• Overall oxygen needs may decrease with reduced activity

What Affects Breathing Efficiency

Water Temperature

Temperature dramatically impacts all three breathing methods:

60-64°F (ideal range):

• Maximum dissolved oxygen in water
• Gills work efficiently
• Minimal surface breathing needed
• Skin absorption optimal

65-70°F (acceptable range):

• Reduced dissolved oxygen
• Increased surface breathing frequency
• Gills work harder
• Higher metabolism needs more oxygen

71-75°F (stress range):

• Significantly reduced dissolved oxygen
• Frequent surface breathing
• Gills struggle
• Risk of oxygen starvation

76°F+ (dangerous range):

• Critical oxygen shortage
• Near-constant surface breathing
• Gill damage risk
• Emergency situation

Water Flow and Circulation

Movement in the water affects breathing:

Gentle flow keeps fresh, oxygenated water flowing over gills and skin constantly. This maximizes breathing efficiency.

Stagnant water creates zones of depleted oxygen where the axolotl has already extracted available oxygen. This forces more surface breathing.

Too-strong current exhausts the axolotl and can damage delicate gill filaments. This reduces breathing efficiency despite good oxygen levels.

Oxygen Levels

Dissolved oxygen concentration is the most critical factor:

High oxygen (8+ ppm): All breathing methods work easily, minimal effort needed

Moderate oxygen (5-7 ppm): Normal breathing patterns, occasional surface trips

Low oxygen (3-4 ppm): Frequent surface breathing, stress indicators appear

Critically low (<3 ppm): Life-threatening, constant surface gulping, emergency intervention needed

Water Quality

Poor water quality impairs all three breathing methods simultaneously:

Ammonia burns gill filaments, damages skin permeability, and irritates lung tissue

Nitrites interfere with oxygen transport in blood, making breathing less effective

High nitrates stress the system overall, increasing oxygen needs

Wrong pH damages gills and skin, reducing their breathing capability

Signs of Breathing Problems

What to Watch For

Recognizing breathing distress early prevents serious health issues:

Constant surface breathing (every few minutes) indicates oxygen crisis

Gasping at the surface with mouth wide open shows severe distress

Curled or clamped gills suggest gill damage or irritation

Pale gills indicate poor circulation or reduced blood oxygen

Floating at surface unable to sink may indicate lung overinflation or inability to expel air

Sitting completely still with minimal gill movement suggests exhaustion or shutdown

Rapid gill beating shows the axolotl is working hard to extract oxygen

Emergency Response

If you notice breathing problems:

1. Test water immediately – Check ammonia, nitrites, nitrates, pH, and temperature
2. Do a 50% water change with treated, temperature-matched water
3. Add an airstone to increase dissolved oxygen quickly
4. Lower temperature if above 68°F using frozen water bottles
5. Remove stressors like bright lights or aggressive tank mates
6. Monitor closely and be prepared to move the axolotl to a hospital tank

Most breathing emergencies stem from water quality issues that can be corrected quickly if caught early.

Frequently Asked Questions

Can axolotls drown?
Technically yes, if they can’t reach the surface for supplemental air breathing in low-oxygen water. However, their gills usually prevent true drowning.

Do axolotls need air bubblers?
Not necessarily, but air stones help maintain oxygen levels, especially in warm weather or crowded tanks. They’re good insurance.

Why is my axolotl at the surface constantly?
This usually indicates low dissolved oxygen from warm water, poor circulation, or water quality problems. Test and correct conditions immediately.

Can axolotls breathe out of water?
For short periods (5-10 minutes), their skin and lungs can sustain them. However, gills dry out and become damaged, and they can’t survive long-term outside water.

Do gills grow back if damaged?
Yes, axolotls can regenerate damaged gill filaments over several weeks if water conditions improve. Severe damage takes longer to heal.

Why are my axolotl’s gills small and curled?
Poor water quality is the most common cause. Test parameters and do water changes. Stress, genetics, and high flow can also cause curled gills.

Is it normal for axolotls to yawn?
Yes, what looks like yawning is actually the axolotl clearing its gills or adjusting water flow through its mouth. This is normal behavior several times a day.

Do different color morphs breathe differently?
No, all axolotl colors have the same respiratory system. Color doesn’t affect breathing ability or methods.