Seal pups are a case study of an adorable baby animal - and like several other mammals, they are incredibly vulnerable for the first few weeks of their lives. In the Autumn, female seals (cows) return to the same place they themselves were born to give birth to just one pup.  Newborn seals typically weigh just over 10kg. They're thin and baggy looking, with their tiny bodies covered with yellow stained fur. At this stage, pups are not strong swimmers and can't hunt for themselves, so they rely on their mother’s fat-rich milk to build up their strength. In this three-week nursing period, pups must put on enough weight to survive for the next few weeks on land, until they are ready to enter the sea and begin hunting for food themselves.

The pup will feed up to 6 times a day for up to 10 minutes each time. Every feed is crucial, and it only takes a few missed feeds for a pup’s chance of survival to be reduced from slim to none.

Over this feeding period, seal pups rapidly transition from small, white, and fluffy to plump, round and barrel-shaped. By the time they're two weeks old, they begin to moult; they lose their white fur, revealing a grey coat with a unique individual pattern that they will keep for life. At three weeks, seal pups can weigh more than three times their birth weight!

This early stage is a very vulnerable time for grey seals, and the survival rates of pups to the age of one is very low. However, this fast growth during the first few weeks of their lives gives them a greater chance of survival. The pup will remain on land for another month or so until hunger eventually drives them to the sea. Then, they have to teach themselves through trial and error to catch fish and crabs for food, learning to survive on their own.

Seal mothers will leave its pup to fend for itself after three weeks, she will now mate again before leaving the haul out site. Female seals become receptive to mating straight after giving birth which can be quite dangerous for the pup as large male seals (bulls) will approach the mother while she’s still feeding her pup. The males can be quite aggressive and may trample the pup while fighting off other males for the female’s attention.  

Disturbing seals can have a number of impacts to the mother and pup.

1. It can result in the mother abandoning her pup, if she does not return often enough to feed it the pup will starve and die in just a couple of days.
2. If the pup is disturbed it may get frightened into the water before it is strong enough, resulting in drowning. It may also drown after being swept into the water on a large spring tide.
3. It can lead to starvation of the mother as she uses up vital energy stores as she flees a perceived risk. Seal mums fast during the 3 weeks she feeds her pup and during this time she passes on a large proportion of her energy stores, helping her pup to increase its body weight by up to 10kg each week. She can lose around a quarter of her body weight during this time. However, she must also conserve enough energy (stored as blubber) to fuel hunting activities and to keep warm in the cold seas once her pup has weaned.

As well as being as vulnerable to disturbance, young seals are prone to infection to the eyes and respiratory tract.

The grey seal colony at South Walney Nature Reserve is the only seal colony in the North West of England. Seal pups have been born here each year since 2015. We survey the seals over the pupping season to monitor breeding success, colony size and disturbance events. There is no access to the beach to allow the seals to haul out safely without the risk of disturbance by humans (and their dogs). The best place to watch the seals is from Groyne Hide at high tide where you can watch the seals playing in the sea, with binoculars you may also be able to spot seals hauled out further away along the spit. You can also watch the seals on our live Seal Cam. Following a number of disturbance events this year we are appealing to all sea users including kayakers, anglers and boats to maintain at least 100m distance from the seal colony at all times during the pupping season and to follow guidance from the government’s Marine & Coastal Wildlife Code.