National Trust records huge increase in number of seal pups born at Orford Ness in Suffolk

Matt WIlson, Countryside Manager for the National Trust’s Suffolk and Essex Coast portfolio, says: “This year, our peak counts have included 803 adults and 430 pups, which is by far the highest numbers we’ve seen since the grey seals’ arrival in 2021.”

The first 200 adult seals arrived at the site in 2021, after an extended period of closure due to the pandemic, when visitor access was significantly reduced. Since then, numbers have increased year-on-year as the colony has established.

Orford Ness, a former 20th century military testing site that’s been left to nature, is now believed to be home to Suffolk’s first breeding colony. In 2021-22, 25 grey seal pups were born, followed by 66 in 2022-23, 133 in 2023-24 and 228 in 2024-25.

Global numbers of grey seals are estimated to be around 300,0001, with British and Irish waters supporting around 40 per cent of the world’s grey seal population.

In the wild, female grey seals, known as cows, can live for 30-35 years, whilst males live for about 20-25 years. Cows have their first pups between the ages of three and five and usually return to the same place each year to give birth.

Matt continues: “We’re now in the fifth consecutive year of successful breeding at Orford Ness, which means that some of the adults having pups this year would have been born at Orford Ness in 2021 and 2022. It’s a good sign that the habitats are healthy, with enough fish stocks to keep them sustained throughout the winter, and the shingle ridge providing shelter from storms.

“Orford Ness is also closed from the end of October until the spring, which coincides with pupping season. That means the likelihood of human disturbance is greatly reduced, which no doubt adds to their overall health and wellbeing and has so far helped them to thrive.”

Disturbance is one of the biggest threats to grey seals on UK shores and includes any human activity that can cause them to change their natural behaviour. This includes the use of drones or other aerial equipment, which can cause just as much disturbance as approaching on foot.

Orford Ness is open on select days between 4 May and 26 September 2026 and its abundance of wildlife includes several species of nesting and wading birds, hares, Chinese Water Deer and precious vegetated shingle. There is no visitor access to see the seals, even on open days, although some individuals from the colony can often be seen swimming along other areas of the coast, including between Aldeburgh and Shingle Street.

Throughout pupping season, National Trust rangers have carried out weekly counts and checks as part of their winter work – all from a safe distance.

Tom Allen, ranger at Orford Ness, who has been conducting the counts, says: “It’s been fantastic to see the colony grow over the past few months – although with much bigger numbers, and typically wintry weather, it can make counting difficult!

“Seals are wild animals and therefore move around, which occasionally means we’re unable to even get to some of their locations without the risk of disturbing them.

“We use a combination of telescopes and binoculars to help, which allows us to monitor the size and health of the colony from a safe distance, but as the colony gets bigger, it’s likely that our counts will become estimates rather than final numbers. We try to be as accurate as possible, but there is always a chance that some may have been missed.”

This year, fierce winter storms, including Storm Goretti, caused some of the adults and pups to become displaced, as the shingle beach, which makes up Orford Ness’ ten-mile spit, shifted with the weather.

Matt continues: “Fortunately, the most noticeable storm surge occurred when most of our pups had moulted, which is when they lose their fluffy white coat and are able to swim. This meant that they are able to survive in the water, and the remaining white coats were still spotted on the shingle beach during our post-storm checks.

“Although we do lose some pups each year to storm events like this, or sometimes to a few cases of female pups abandoning their young, we still appear to have a very low mortality rate, even as the colony continues to grow.”

The National Trust team is continuing to work with a number of partner organisations to help support the colony, including the Sea Mammal Research Unit (SMRU) at St Andrew’s as well as British Divers Marine Life Rescue (BDMLR), WildlifeWise and the specialist RSPCA rescue centre at East Winch in Norfolk.