How Do Penguins Swim and Dive So Well? [and Other Questions]

Penguins are aquatic birds that spend the majority of their lives in the water. As far as birds go, they are the strongest swimmers and can dive deeper than humans, but how do penguins swim so well?

Penguins are excellent swimmers and divers because they have streamlined bodies, flippers that they use to propel themselves through the water, and webbed feet which they use to steer to navigate. When underwater, penguins can also reduce their metabolic rate to function with lower oxygen and drop their heart rate as low as 15bpm which enables them to swim more efficiently.

Keep reading to find out how deep, fast, and far penguins can swim. or see our full article for some interesting facts about penguins.

How Are Penguins So Good At Swimming?

Penguins may spend around 75% of their day-to-day life in the water and if they are not breeding may not visit land for several months at a time¹ (source: S. Moss, Do Birds Have Knees, 2016). Penguins are able to do this because their bodies have evolved certain characteristic features that make them strong swimmers:

• Streamlined bodies – Their bodies are streamlined for cutting through the water and their oily feathers not only insulate the bords but also allow water to glide more smoothly over their bodies as they swim below the surface² (source: Penguins International).
• Flippers – They use their flippers like propellers when swimming below the surface and when diving. Whilst their flippers also help with the ascent, the buoyancy of their bodies also plays a key role.
• Air bubbles under Feathers – Whilst out of the water, penguins fluff their feathers to add a layer of air underneath them. When they ascend from deep depths, the air is forced out through their tightly pressed feathers as a small airstream of bubbles which can reduce the water friction by up to 80%³ (source: J. Davenport, et al, Marine Ecology Progress Series, Vol. 430, 2011).
• Webbed feet – Penguins have short webbed feet which are set far back from their bodies, they use these to help to steer whilst swimming, much like the udder of a boat.

As penguins swim near the surface, they can be seen jumping in and out of the water like dolphins and other sea birds, this is called porpoising. This allows them to swim at high speeds whilst still catching breaths of air as they jump out of the water⁴ (source: T.N. Davies, University of Alaska Fairbanks, 1981). This technique can also be used to avoid marine predators by landing the birds a safer distance inland from the shoreline.

How Fast Can Penguins Swim?

Penguins are the world’s fastest swimming birds. When chasing prey, they can reach speeds of up to 15km/h (9.3mph)⁵ (source: S. Moss, Do Birds Have Knees, 2016). Generally, most penguins swim at an average of 5-7 km/h⁶ (source; P.D. Boersma and P.G. Borboroglu, Penguins: Natural History and Conservation, 2013).

The Gentoo Penguin is one of the fastest penguin species and has been recorded reaching speeds of 35km/h (22mph)⁷ (source: S. Moss, Do Birds Have Knees, 2016). In comparison, the slowest swimming penguin is the Little Penguin which only reaches a speed of around 1.5km/h (1mph)⁸ (source: The Smithsonian Institution).

How Deep Can a Penguin Dive in the Ocean?

They must be good at diving since a typical penguin diet includes fish, squid, and small crustaceans such as krill, all of which must be caught in the ocean.

The maximum dive depth for penguins in the ocean ranges from 52m for Galapagos Penguins to more than 500m for Emperor Penguins. However, on a daily basis, most penguin species do not dive beyond 100m when foraging for food.

Penguins use visual sight when foraging underwater. This is why they tend to dive deeper in the day than at night. For example, Macaroni Penguins typically dive between 15-60m during the day although only 3-6m at night¹⁰ (source: P.D. Boersma and P.G. Borboroglu, Penguins: Natural History and Conservation, 2013).

There can even be dive depth differences between colonies of the same species as a result of local habitat adjustments and Magellanic Penguins are a good example of this.

At Punta Tombo in Argentina, they can dive for up to 3 minutes to depths of around 30m, whereas those in other areas of Argentina can dive for around 1-2 minutes to around 55-60m¹¹ (source: P.D. Boersma and P.G. Borboroglu, Penguins: Natural History and Conservation, 2013).

Below is a table that outlines the dive depths and times for various penguin species around the world.

How Long Can A Penguin Stay Underwater?

The duration that a penguin stays underwater is not determined by time but by the amount of energy that a penguin has used related to oxygen consumption rates.

In a study, researchers found that Penguins use the number of wing strokes as an indicator of when to turn around and return to the surface which is an indicator of the cumulative muscle use and muscle memory adaptations.

The researchers found that Emperor Penguins will continue their dive until they have made an average of 237 strokes of their wings. This is why they stay underwater for much longer during shallow dives through ice holes as this requires fewer wing strokes and less energy compared to the deeper dives at sea to catch prey¹² (source: K. Shiomi, et al., Journal of Experimental Biology, Vol 215, 2012).

How Far Can Penguins Swim?

Mellagenic Penguins from South Africa can swim more than 170km per day while foraging for prey¹³ (source: P.D. Boersma, et al., Ecological Monographs, Vol. 79, Issue 1, 2009). Penguins can sleep at sea which allows them to undertake multi-day foraging trips.

In comparison, Fiordland penguins are known to swim 7000km in a single journey from their breeding grounds in New Zealand to the Sub-Antarctic Front and back again, a journey that lasts 8-10 weeks¹⁴ (source: T. Mattern, Plos One, 2018).

What Adaptation Allows Penguins to Dive Deep Underwater?

Emperor Penguins are especially well adapted to the water. They can stay underwater for long periods of time because they can slow down their metabolic rate and still function with low levels of oxygen.

During a dive, they might reduce their heart rate as low as 15 beats per minute and can shut down any internal organs that aren’t in use and their strong bones also allow them to withstand high pressures at depth.

An Emperor Penguin can withstand the pressure that’s 40 times greater than at the surface which would kill any human without specialist gear¹⁷ (source: S. Moss, Dynasties, 2018).

Why Don’t Penguins Get the Bends?

When mammals dive deep underwater, the increasing pressure causes nitrogen from the air in their lungs to dissolve into the body tissue. If the nitrogen is not returned to the lungs before surfacing, it can cause bubbles which are dangerous.

This is known as decompression sickness and in humans can result in symptoms such as muscle pain, weakness, and vertigo¹⁸ (source: Healthline).

Most marine mammals have a way of dealing with decompression and for example, whales and seals can squeeze out the air before they dive. However, penguins have a unique diving strategy for dealing with this.

When returning to the surface, penguins swim for 70-80% of the ascent and then rely on their buoyancy for the remainder. As they near the surface, they ascend at a greater angle which slows them down, this allows the nitrogen to leave their tissue and prevents decompression sickness, also known as the bends¹⁹ (source: Katsufumi Sato, et al., Journal of Experimental Biology, Vol. 205, Issue 9, 2002).

Related Questions

Are Penguins Faster Swimmers Than Humans?

Yes, most penguins are faster swimmers than penguins as they can reach speeds up to 15km/h (9.3mph) compared to the fastest human swimmers which reach about 8km/h (5mph). However, some penguins are slower than humans, such as Galapagos Penguins which swim about 1.5km/h (1mph).

Can Penguins Live Without Water?

No, penguins would not be able to survive without water because they catch all of their prey in the ocean. They have become adapted to spend most of their lives in the water, as much as 75% of their daily life and up to months at a time.

How Fast Do Penguins Run?

Penguins’ webbed feet are evolved to help them be better swimmers, however, they are not very useful on land so penguins can only run at speeds up to 4km/h (2.5mph). Some species are known to slide on their bellies as a way of moving around faster on land, this is called tobogganing²⁰ (source: Sciencing.com).