Seals are a part of the Pinniped family, which is made up of a diverse range of semi-aquatic marine mammals. Because they are semi-aquatic, seals have a lifestyle that allows them to spend periods of time in the ocean and on land. Despite spending time on land, seals are able to spend a considerable amount of time underwater which leads many people to wonder “how long can seals hold their breath?”.
While seals cannot hold their breath for as long as some of their other mammalian counterparts, like whales, seals are still able to dive to incredible depths and thrive in a marine environment.
How long can seals hold their breath?
The longest dive for a seal recorded was made by an Elephant Seal which remained underwater for 2 hours! Spending this much time underwater is likely not typical though and most seals will spend anywhere from 3 to 30 minutes underwater.
How can seals hold their breath for so long?
Diving marine mammals, like dolphins, whales and seals have very high concentrations of a protein called myoglobin in their muscles. Myoglobin is an iron and oxygen binding protein that allows for diving marine mammals to increase the amount of oxygen stored in their muscles throughout the body.
Land dwelling mammals, including humans, also have myoglobin which makes our muscular system appear red. But seals and other marine mammals have so much myoglobin their muscles look nearly black.
Not only that, but when making deep dives, seals will slow their heart rate which in turn conserves oxygen. When they’re not trying to conserve oxygen, a regular heartbeat for seals is anywhere between 75-125 beats per minute. But when making a dive, seals can slow their hearts to 4-6 beats per minute!
How deep can seals dive?
In addition to holding the record for longest breath hold, Elephant Seals also hold the record for deepest dive. Elephant Seals can dive to depths of over 1,500 meters (~5,000 feet!).
While seals are capable of making deep dives, they tend to stick to shallow waters and may only dive down a few hundred feet at a time. Oftentimes, seals can find everything they need in shallow waters and don’t always need to dive deep!
How do seals breathe?
Seals are air breathing mammals that inhale oxygen into their lungs and exhale carbon dioxide- just like humans. Unlike other marine mammals, seals do not have blowholes that they use to inhale air. Instead, all inhalation and exhalation happens through the seal’s nostrils.
Can seals breathe underwater?
No, mammals like seals are not able to breathe underwater. Seals need to come to the surface to breathe. In order to keep water out of their respiratory system, their nostrils will almost pinch close while seals are underwater.
Do seals have gills?
No, seals do not have gills. Seals, like whales and dolphins are marine mammals that have lungs to breathe in air- just like humans!
How much time do seals spend in the water?
There are 33 species of pinnipeds or seals, and it’s likely that the amount of time they spend in the water will change between species. Some species split their time equally between the ocean and being on land.
Elephant Seals typically spend about 80% of their time in the water or at sea and come to shore to breed and reproduce. In contrast, most Harbor Seals spend only 50% of their time in the water.
Do seals sleep underwater?
Seals don’t sleep completely submerged or underwater. But seals can sleep partially submerged in the water, but they also sleep on land. One benefit of being semi-aquatic for seals is to choose their resting sites, whether that is in the water or on land.
Seals may sleep on land in cooler weather, or when they have pups. Sleeping on land can also be safer if there are potential predators like sharks or orcas in the area.
However, when seals sleep in the water, they sleep with their body positioned vertically with their head towards the surface. This position is called “bottling” and can look a little strange! But seals sleep this way so that their snout with their nostrils can remain above the surface.
Do seals eat underwater?
Yes, seals do most if not all of their hunting while in the water. While they are capable of being on land, seals are not very graceful on land and would likely have a hard time catching anything to eat on land.
Seals are much quicker in the water, which allows them to hunt down fish and other prey. In order to prevent swallowing a mouthful of seawater during a meal, seals will move their tongue to the back of their mouth to block the stream of water.
How much time do seals spend on land?
Different species of seals will behave differently in terms of how much time they spend on land. Harbor Seals, for example, spend about 50% of their time on land.
The first few weeks of a baby seal’s life will be spent online, and the mother will spend time returning to the shore to nurse the pup in addition to spending time at sea to replenish her nutrients.
The pinniped family includes many species of seals and sea lions, all of which are capable of holding their breath to dive down- with some seals being able to dive down several thousand feet! Many people associate marine life with having gills, but this is absolutely not the case with seals and other marine mammals.
Marine mammals are truly a dynamic group of wildlife that have evolved to survive one of the harshest environments on earth, the ocean. Seals are exceptionally dynamic due to the fact that they are not constrained to land or sea, and have adaptations that allow them to survive their ever changing habitats.