How Sharks Breathe

Inspired by The Shark Whisperer Documentary, just released on Netflix - a breathtaking exploration of how Ocean Ramsey, a rare breed of human who adores swimming alongside sharks, reveals the extraordinary nature of these magnificent creatures.

With over 50% of the oxygen we breathe being produced from tiny marine plants called phytoplankton that float in the sunlit surface waters, and the remaining oxygen coming from terrestrial plants like trees and forests, this breathtaking footage within this programme has left us curious about how sharks breathe.

How Sharks Breathe

Sharks have evolved sophisticated respiratory systems that challenge common misconceptions about their breathing requirements. Unlike mammals with lungs, sharks extract dissolved oxygen from water through specialised gill structures, but their breathing mechanisms are far more complex and adaptable than traditionally understood.

Gill Structure and Function

Sharks can have up to seven external gill openings, but most species have five, located on either side of their head. Gills possess tissues resembling short threads, referred to as gill filaments or lamellae. Each filament contains a capillary network that provides a large surface area for exchanging oxygen and carbon dioxide. This extensive surface area maximises oxygen extraction efficiency from the surrounding water.

Two Primary Breathing Methods
Research has identified two distinct respiratory strategies employed by sharks:

Ram Ventilation

All sharks can use "ram ventilation", which is the forcing of water over the gills by swimming motions. This method involves swimming with the mouth open, allowing water to flow directly over the gills as the shark moves forward. Research with remoras – bony fishes that can switch between the two fish breathing methods – found that maintaining the same volume of water/gill flow with buccal pumping consumed as much as 5.1 percent more energy for the fish than ram ventilation, making this the more energy-efficient option.

Buccal Pumping

Some sharks are bottom dwellers, and have adapted to "buccal pumping". Buccal pumping is the forcing of water over the gills by opening and closing the mouth. Some sharks, however, can get enough oxygen when they are not swimming by gulping water into their mouth, then forcing the water out through the gills with muscular contractions of the orobranchial cavity.

Debunking the "Keep Swimming" Myth

Contrary to popular belief, It is not true that all sharks must always keep swimming to breathe. The necessity for sharks to keep swimming to breathe is more complex than previously thought. While ram ventilation is a common strategy among many species, sharks exhibit a range of behaviors and physiological adaptations that allow them to regulate their respiratory needs.

Research demonstrates that sharks can adapt their breathing strategies based on environmental conditions and energy requirements. In a study of lemon sharks, which switch between breathing methods, juveniles breathed 6 per cent more efficiently when moving than when resting, even when resting so that the current allowed the water to flow directly into their mouths.

Adaptive Respiratory Strategies

Modern research reveals that sharks exhibit a range of behaviors and physiological adaptations that allow them to regulate their respiratory needs. These adaptations include changes in swimming speed, gape size, and metabolic rates, which are influenced by factors such as body size, temperature, and environmental conditions.

Some bottom-dwelling shark species have evolved specialized adaptations, including spiracles (small openings behind the eyes) that allow them to draw water over their gills even when resting on the seafloor, further demonstrating the remarkable flexibility of shark respiratory systems.

Shark respiration represents a sophisticated biological system that has evolved multiple strategies to ensure adequate oxygen uptake across diverse marine environments. Rather than being obligated to perpetual motion, sharks demonstrate remarkable respiratory flexibility, employing both active swimming-based ram ventilation and stationary buccal pumping as circumstances require. This research-backed understanding corrects long-held misconceptions and highlights the remarkable adaptability of these ancient predators to their aquatic environment.

Shark Breathe 

A breathing exercise for older children (ages 8-14)

The Science Behind It
Just like sharks use two different ways to breathe underwater - ram ventilation (breathing while swimming) and buccal pumping (breathing while resting) - we can learn to breathe efficiently whether we're moving or still!

How to Do Shark Breathe
1.Ram Ventilation Breathing (Active Shark)
For when you need energy and focus

Stand up and "swim" on the spot

Make gentle swimming motions with your arms (breast stroke for nasal breathing!)
Keep moving your body like you're gliding through water

Breathe with the flow

Breathe in through the nose for 4 counts as you "swim" forward
Breathe out for for 4 counts as you continue moving
Imagine water flowing over your gills as you move

Continue for 1-2 minutes

Keep the gentle movement going
Feel how your breath flows naturally with movement
This energises you, just like an active shark!

2.Buccal Pumping Breathing (Resting Shark)
For when you need to calm down and rest

Find your "seafloor" position

Sit comfortably or lie down
Imagine you're a nurse shark resting on the ocean floor

Place one hand on your chest, one on your belly
Breathe in slowly through your nose (like gulping water)
Let the air out gently through your mouth (like blowing water over gills)
Breathe in for 4, pause the breath for 2, breathe for 6

Continue for 2-3 minutes

Stay completely still like a resting shark
Focus on the active pumping of your breath
Feel yourself becoming calm and grounded

When to Practice?

Use Ram Ventilation Breathing when you:

• Need energy for sports or activities
• Want to focus before a test
• Feel sluggish or tired
• Need confidence boost

Use Buccal Pumping Breathing when you:

• Feel anxious or stressed
• Need to calm down after excitement
• Want to relax before sleep
• Feel overwhelmed

Fun Shark Facts to Remember

• Not all sharks need to keep swimming to breathe!
• Some sharks can switch between both breathing methods
• Bottom-dwelling sharks are experts at "buccal pumping"
• Swimming sharks use 5% less energy than pumping sharks

The Shark Breathe Challenge

Try switching between both types of breathing just like real sharks do! Start with 2 minutes of Ram Ventilation, then immediately switch to 3 minutes of Buccal Pumping. Notice how different your body and mind feel with each method.