Here we answer some of the internet’s most frequently asked questions about seals: some of the questions and answers may surprise you!
We also have a fantastic Seal Facts page if you want to learn more!
Why do seals slap themselves/ their bellies?
Seals slap their bellies in order to send a message to other seals. It lets them communicate to perceived threats that they are strong and alert. These slaps will emit warning signals via low-frequency sound waves which can be picked up by other seals thanks to their acute hearing.
Why do seals look like dogs?
Seals and dogs share physical similarities because they are closely genetically related. Both seals and dogs are found within the sub-order Caniformia. Another group of animals in the same sub-order are bears, who are even more closely related to seals than dogs are!
Why are seals important?
Seals have inhabited Irish coastlines for thousands of years playing a critical role in balancing the ecosystem and recycling nutrients. They are considered ‘doctors’ of the sea by removing sick or weak individuals from prey populations and leaving the strong and healthy individuals to go on and reproduce, thus driving the evolution of many prey species. Due to this vital role at the top of the food chain, they are considered a “keystone species” as they have a disproportionately large impact on the ecosystem in which they reside.
Seals also play an important role as a “Bio-indicator” species, which means we can monitor their populations, behaviours, and health for key insights to better understand marine biodynamics of a given ecosystem.
Why are seals fat? Do all seals have fur?
Like all mammals, seals have fur (although they often appear slimy when wet, but when dry their fur is soft and fluffy!). Many seal species live in cold regions and feel the effects of this cold when they spend so much of their time in the water. Because of this, seals have developed a layer of fat called “blubber”. Blubber covers their body under the skin and is filled with blood vessels. These vessels transport blood around to keep the seal warm. When a seal dives into especially cold water, the blood vessels in the blubber contract, preventing heat loss from the body into the frigid outside conditions. All seal species also have fur to keep them warm and insulated as well. 11 species of Pinnipeds live in the Arctic Circle, and therefore need to be especially fat to keep warm! These are: Harbour Seals, Grey Seals, Bearded Seals, Arctic Seals, Ringed Seals, Spotted Seals, Ribbon Seals, Harp Seals, Northern Fur Seals, and Walruses.
Are seals endangered?
Of the 34 living species of Pinnipeds (True Seals, Sea Lions, and Walruses), 9 are currently considered threatened and appear on the IUCN Red List. Included in these threatened species are the Walrus, the Northern Fur Seal, and the Hooded Seal. In Ireland, the Grey Seal was almost hunted to extinction until legal protections were introduced in the 1970s. Since then, the numbers have slowly recovered, but are still a very small percentage of what they once were.
Which mythical beliefs relate to seals?
There are many myths surrounding seals, particularly in Celtic and Norse areas of the world. One example is the myth of “Selkies”, creatures who can change their skin to take on either a seal or human form. The ancient Celtic folklore tale of the Tuatha Dé Danann tells of how the first seals of Ireland came to be, as babies thrown into the sea were magically changed into seals when touched by the God of the Sea. In other Irish folklore, many believed that seals were the spirits of sailors or fishermen that were lost at sea.
Will seals evolve into whales?
No, seals are not evolving into whales. While both animals show similar traits and have evolved from creatures with similar appearances, this is merely an example of convergent evolution. Evolution doesn’t have an end goal in mind and doesn’t actively move creatures towards certain pre-set forms.
What do seals eat?
Many of seals’ food sources have disappeared because of unsustainable fishing practices. As a result, seals have needed to work harder and become more opportunistic to survive. This means they will eat anything that’s available to them.
In Ireland, it is predicted that Sandeels, Cod and Dover Sole account for 56% of a Grey Seal’s diet by weight, and also eat other flatfish, including Dab, Flounder and Plaice. A Grey Seal’s diet varies by location, though they are largely demersal or benthic feeders, (meaning that they feed off of the bottom of the seafloor). Harbour Seals eat many similar species, but they are more generalist feeders that take a wide variety of fish, cephalopods, and crustaceans obtained from the surface, mid-water, and benthic habitats. Their diet is highly varied, and animals from different populations and areas show differences. There is also variation associated with seasonal changes in the abundance of prey.
What species of seal live in Ireland/UK?
There are 2 native seal species living in Ireland and the UK: the Grey Seal (Halichoerus grypus) and the Common/Harbour seal (Phoca vitulina). There have been other species that have been found on our shores, including Bearded Seals, Hooded Seals, and an Arctic Ringed Seal we rescued and cared for in 2020 called Cloudberry and Wally the Walrus in 2021. However, none of these species are considered permanent members of the Irish and UK seal population.
When and where do seals sleep?
Seals tend to come up onto the shore to sleep. They spend around half of their time on land, with roughly 75% of that time spent resting. Seals can also rest in the water, sleeping with half of their brain still active!
When do seals give birth?
The pupping season for Grey Seals ranges from Late Summer, into Autumn/Winter (August – January) while Common Seals pup during the Summer (June-September), returning to the same place every year to breed and give birth. While Winter seems an odd time to give birth for Grey Seals, a possible explanation for why is because the females are in better shape after a summer of eating fish to produce enough rich, fatty milk to feed their young.
How do seals swim?
Seals swim by moving their back flippers from side to side, propelling them through the water, while they use their front two flippers to give direction and steer. Grey and Common seals dive on average up to 100m however they have been recorded as deep as 500m!
How long are seals pregnant for, and how do they give birth?
Seals mate in the water after their pupping season. The total gestation period for seals lasts 9-11 months, with dates of pupping changing depending on the sea-surface temperature. They normally give birth on land. If you see a seal pup that may be in trouble you can use our rescue line.
Can seals breathe underwater?
Seals are semi-aquatic marine mammals and therefore cannot breathe underwater, so they hold their breath when they dive. While the average dive for greys and commons is 5-10 minutes, they are capable of being underwater for a maximum time of around 30 minutes. Larger pinnipeds are capable of staying underwater for much longer, for example, southern elephant seals can hold their breath for up to 100 minutes!
Can seals live on land?
Seals are semi-aquatic, which means that although they are built for life at sea, they must have access to land as they spend roughly half of their time hauled out to rest, digest their food, re-oxygenate their blood, nurse their young and socialize. Although seals must have access to water to hunt and travel, it is perfectly normal to observe seals on land and is vital to respect them from a safe distance to avoid disturbing their natural behaviours and wasting their vital energy stores.
Seals will also come to shore in great numbers during the pupping seasons and when moulting their fur (July-August for Harbour Seals, December-January for Grey Seals). Unlike Sea Lions, seals have short front flippers and un-rotatable back flippers meaning they can’t lift themselves up off the beach to move or make a quick escape. The seals move on land by a method called ‘galumphing’; undulating their body to create forward momentum. This means they are slow-moving on land and vulnerable to disturbances.
Where can seals be found?
Seals have a worldwide distribution and can be found in most coastal areas, however, they are particularly abundant in cold polar waters. The distribution also varies greatly between species; grey seals occupy a relatively small area with over 40% of the entire population resident to the UK and Ireland, whereas common seals are the most widely distributed pinniped and can be found in coastal waters of the northern Atlantic and Pacific oceans and Baltic and North seas.
Can seals live in freshwater?
All seals can tolerate living in freshwater, however, the only species to live exclusively in freshwater is the Baikal seal.
Can seals have twins?
Seals usually give birth to a single pup with the reproductive system of pinnipeds not favouring twins, however, twins (of both grey and common seals) have been recorded to have survived to weaning both in captivity and the wild.
Can seals drown?
As seals are mammals that use lungs to breathe oxygen, it is possible for seals to drown. This most commonly occurs when young pups without fully developed lungs or swimming muscles get caught in storms and become exhausted. Adult seals are also capable of drowning if forced to stay underwater for longer than their lungs can hold oxygen, such as when they become entangled in fishing gear under the surface.
Are seals friendly?
Seals are curious animals and occasionally seek out interactions with scuba divers, but they are wild animals and are generally not naturally friendly towards humans. They are mostly solitary and are usually only seen in large groups during pupping and mating seasons.
Can seals be aggressive or harm humans?
If you see a seal in the wild, make sure you keep a distance of at least 100m, and treat the wild animal with the care and respect it deserves. As long as you follow these steps, a seal should not be aggressive towards you. Seals are large, powerful animals with sharp teeth and strong jaws, and will bite if they feel threatened. In humans, if a seal bite were to become infected by the bacteria Mycoplasma phocacerebrale, it can lead to a painful infectious disease known as “seal finger” as well as other complications.
Are seals dangerous to dogs?
Seals can become aggressive when approached or attacked by dogs (which is, unfortunately, a common problem as dogs are so popular!). As seals are built for speed and agility in the water, they are slow to escape on land which leaves them vulnerable to attacks and explains why they will bite when provoked. With strong jaws and sharp teeth, they can cause serious injury. Seals are genetic cousins to dogs, so they can spread zoonotic diseases to one another. This is why it is extremely important, for the safety of both seals AND dogs, to always keep a distance of at least 100m from any seal you see in the wild, and always keep your dog on a lead if you think there is a chance it may encounter a seal.
Are seals and sea lions the same?
While seals and sea lions, along with walrus, are part of the same suborder of Pinnipedia, they do have several traits which make them unique. Seals are part of a family called Phocidae, also known as true seals, while Sea lions are part of the family called Otariidae, commonly known as eared seals. While the 2 families are closely related the names aren’t interchangeable. One difference between seals and sea lions is that seals have internal ears, whereas sea lions have external ear flaps visible on their profile. Sea lions are capable of rotating their joints on their flippers to lift themselves off the land and “walk”, whereas true seals always remain more or less flat along the land, gyrating their bodies to “galumph” on land. Sea lions use their front flippers for propulsion and their back flippers for steering, but it’s the opposite for true seals who use their back flippers for propulsion and front flippers to steer.
Why are seals evil? Which seals eat penguins?
Seals, like any animal, are not capable of being “evil”. While seals can become aggressive when threatened, or predate other animals (including charismatic animals like penguins) this is just their natural behaviour and is required for their survival. Of the 33 species of seals, there are only 5 that have been recorded eating penguins; the New Zealand Fur Seal, the South American Sea Lion, the Australian Sea Lion, the Weddell Seal, and the Leopard Seal.
The biggest threats to penguins are climate change, pollution, habitat loss, and biodiversity loss brought on by human activities, and are the same threats that many of our seal species face.
