Have you ever seen those adorable zoo otters swimming and diving underwater like little furry torpedoes? They make it look so easy to hold their breath and stay submerged for minutes at a time. Can otters breathe underwater?
The short answer is no. Otters cannot breathe underwater like fish can. But they have some unique adaptations that allow them to hold their breath for up to 8 minutes while hunting and playing underwater!
Can Otters Breathe Underwater?
Otters are mammals, just like dogs, cats, and humans. That means they need air to breathe and can’t extract oxygen from water like fish gills do. But otters are specially equipped for their semi-aquatic lifestyle. Here’s how they can stay submerged for so long:
Highly Efficient Lungs
An otter’s lungs work very differently than human lungs. We take quick, shallow breaths, but otters take very deep breaths, filling up their large lung capacity to the max. This allows them to stockpile more oxygen for their underwater dives.
Otters also have a much more efficient exchange of oxygen than humans. Their lungs are specially adapted to extract almost all the oxygen from each breath. This gives them several minutes of oxygen stored up before they have to return to the surface.
Ability to Slow Their Metabolism
Otters can slow their heart rate and metabolic rate while diving. This helps reduce their oxygen demands, allowing them to stretch each breath of air even further. Their heartbeat drops from around 100 beats per minute at rest to just ten beats per minute while diving!
An Exceptionally High Concentration of Haemoglobin in Blood
Haemoglobin is the protein in blood that carries oxygen. Otters have much higher levels of haemoglobin than humans, which allows their blood to hold more oxygen. They also have a higher concentration of red blood cells. This allows otters to soak up and store more oxygen to fuel dives.
Highly Efficient Use of Stored Oxygen
Otters have adapted to get the most bang for their buck out of every breath. Their organs and tissues are extremely efficient at extracting oxygen from the blood. Very little oxygen is wasted or lost. This allows otters to function for minutes, even though they are cut off from fresh air.
Ability to Override the Diving Reflex
Humans have the “diving reflex” that kicks in when we submerge our faces in cold water. It causes an involuntary slowing of the heartbeat to conserve oxygen.
Otters can override this reflex and speed up their heartbeat while diving. This level of control helps them regulate oxygen use. They can take full advantage of their lung capacity rather than being constrained by an automatic response.
Highly Muscular & Energy Efficient Bodies
An otter’s body is perfectly designed for swimming. Their sleek shape, webbed feet, and powerful tails reduce drag and allow them to propel through the water using very little energy. This helps them get by on less oxygen during dives.
Otters have up to 250,000 hairs per square inch of fur to help trap air bubbles and keep them insulated in cold waters. Their high metabolism keeps them warm. But they can conserve heat by constricting blood flow to the skin and extremities.
Ability to Re-use a Small Amount of Air
Otters have some capacity to re-breathe a tiny bit of air while diving. As they exhale before surfacing, they trap a small “bubble” of air in their lungs. They use this to supplement the next inhale when popping up for another quick breath.
This air recycling and all their other amazing adaptations extend an otter’s underwater time even further. It’s not breathing like a fish, but it squeezes a few more seconds out of each dive.
How Long Can Otters Stay Underwater?
Using all these special adaptations, river otters can hold their breath for an average of 4-8 minutes while swimming and hunting underwater. Their dives typically last about 30 seconds to a minute, but they’ve been recorded staying under for as long as 17 minutes in extreme cases!
Sea otters generally only dive for 1-4 minutes at a time but can hold their breath for up to 10 minutes when necessary. Giant otters, found in South America, can hold their breath for 4-6 minutes on average.
So, while otters can’t breathe underwater like a fish, they can push the limits of their oxygen stores and get by without air longer than almost any other mammal. Their specialized bodies allow them to make the most of each breath, letting them stay submerged for minutes while they play and hunt in their aquatic realm.
How Do Otters Hunt Underwater?
Otters’ many aquatic adaptations help them swiftly swim, dive, twist, and turn to catch prey underwater. Here are some of the techniques they use to hunt while holding their breath:
- Swimming rapidly underwater in pursuit of fast-moving fish
- Plunging head first to the seafloor to grab bottom-dwelling creatures like clams or crabs
- Bobbing in place to scan the water while hunting
- Performing acrobatic twists and rolls to dislodge prey from rocks
- Burrowing through loose sediment on the seafloor to grab hiding animals
- Catching food in their armpits and then bringing it to the surface to eat
- Trapping air bubbles in their fur to retain body heat in cold water
- Using their sensitive whiskers to detect the water movement from swimming prey
- Closing their ears and nose to stop water from entering while diving
- Slowing their metabolism to help extend the time between breaths
- They use webbed feet and a powerful tail to propel themselves swiftly through the water
Otters are like high-speed torpedoes underwater! They are ideally built for diving, swimming, twisting, and chasing prey, all while holding their breath. Their incredible hunting skills allow them to catch slick fish, quick crustaceans, and anything else they can get their little paws on beneath the surface.
What Do Otters Do Underwater?
In addition to hunting prey, otters spend much of their time underwater playing, socializing, and travelling. Here are some other activities otters engage in:
- Frolicking with other otters – their play looks like acrobatic wrestling!
- Chasing and somersaulting through kelp forests and coral reefs
- Searching crevices and overhangs for potential den sites
- Locating and retrieving cached food stores
- Interacting with their pups to teach them how to swim and hunt
- Investigating sunken objects out of curiosity
- Floating peacefully on their backs
- Grooming their thick fur to maintain its insulating and water-repellent properties
- Rubbing their scent on rocks and plants to mark their territory
- Travelling long distances from one area to another
For otters, the water is their playground! Whether they are hunting prey, exploring their surroundings, playing with their friends, or drifting along on their backs, you can be sure otters are having an absolute blast beneath the waves.
How Do Otters Breathe When They Resurface?
As air-breathing mammals, otters cannot stay submerged forever. They must return to the surface every few minutes to take a fresh breath. When otters resurface, they breathe rapidly, gasping for air and hyperventilating to re-oxygenate their lungs as quickly as possible.
Their short, quick inhales and exhales sound almost frantic compared to our own steady breathing. But this rapid breathing is necessary to pull enough oxygen back into their bloodstream and store it up for their next dive.
Otters will often perform a few deep coughs as well to clear any water from their lungs or air passages that may have collected on the dive. Then they’re ready to slip below the waves once more!
The time an otter spends at the surface breathing depends on how long they are underwater and how much energy they exert hunting and swimming. It may only be a matter of seconds if they were just bouncing along the seafloor. Deep dives searching for prey may require 20 seconds of fast breathing to recharge their system fully.
No matter how long they were down, otters waste no time gulping down fresh air once their heads pop up. Their rapid breathing gives them just what they need before the next plunge.
Do Otter Pups Know How to Swim and Dive?
Baby otters, called pups, cannot swim or dive independently when they are first born. They rely completely on their mothers to teach them. Here is how otter pups learn:
- Pups are born unable to swim – they can only doggy paddle and scream!
- The mother floats on her back with the pup lying on her belly for the first few months. This keeps the pup’s head out of water as it nurses.
- Around 2-3 months, the mother will start pushing the pup into the water to begin teaching it to swim and dive.
- She dives under the surface with the pup clutched between her forepaws so it can watch her swim and hunt.
- The mother will retrieve escaped pups repeatedly until they learn to follow her properly underwater.
- Pups first learn to paddle and float on their own. Around 4 months, they can start diving for short periods.
- The mother supervises all dives and hunting at first, then slowly lets the pup practice solo.
- By about 9 months old, otter pups can dive and hunt competently to catch their own food.
Otter moms are extremely attentive teachers. They won’t let their precious pups venture into the water alone until they can swim, dive, surface, and find prey. With this nurturing training, young otters become expert aquatic adventurers!