Why spend 60 years studying seals?

Grey seal pup In one season, 1,500 seal pups will be born on the Farne Islands

Related Stories

In 1951 a small organisation called the Northumberland Natural History Society took an interest in the hundreds of grey seals that lolled on the tiny beaches of the Farne Islands off the north east coast of England.

Every year the seals would crowd ashore and give birth to their pups. The local nature enthusiasts decided to try to find out more about the pups that were born there.

"At that point, we knew hardly anything about grey seals," David Steel, the National Trust's head warden on the Farne Islands tells BBC Nature.

"So they decided to tag 10 newborn pups to see if they could find out where they went, and if they returned to the islands to have their own pups."

Start Quote

Two-day-old grey seal pup

When you're born in November on a rock in the North Sea, it's a tough start to life”

End Quote David Steel National Trust

So, at the beginning of the pupping season, the team attached cattle clips - metal tags marked with the name and address of the organisation - to 10 seal pups' tails.

Three weeks later, the trust received a letter from Norway. A fellow naturalist there had found seal pup number one alive and well on a beach in Stavanger, approximately 650km (400 miles) from the Farne Islands.

John Walton is the islands' property manager. He works for the National Trust, which owns the site.

Head warden David Steel explains how the tagging is done

"That pup swam 400 miles in a maximum of 14 days," he explains. "It was the first real indication, ever, of the distances seals could travel."

This was the beginning of a project that has now been running for 60 years, studying Farne Island grey seals' lives and behaviour.

A tough beginning

Mr Steel is now in the midst of this season's seal count.

Between early October and early December, 1,500 seal pups will be born. Almost half will not make it past the first three weeks of life.

"The pups have to stay out of the water for the first three weeks, when they have their white coat, which is not very waterproof," explains the warden, who spends nine months of the year on the islands.

"But when you're born in November on a rock in the North Sea, it's a tough start to life."

Bull seal on the Farne Islands The Farne Islands is designated a Special Area of Conservation

Storms often wash young pups into the water. And occasionally, young, inexperienced mothers abandon their pups and head out to sea.

"We lost 41% last year," says Mr Steel. "Mother Nature certainly keeps them in check."

Despite the early challenges for every newborn seal, the Farnes population is healthy and slowly and steadily growing. There are almost 4,000 seals on a set of islands, which is designated a Special Area of Conservation (SAC) - meaning it is protected under EU regulations.

This successful human safeguarding of the seals' habitat is a huge turnaround; just a few decades ago, the seal population was deliberately decimated.

The animals used to be thought of as a threat to local fish stocks. And during the late 1960s and 1970s, thousands of seals were shot in a cull that aimed to protect the local fishing industry.

Cow seal with pup
  • Grey seal females are called cows, males are bulls and juveniles are called pups
  • Bull seals can live for up to 25 years, while cows can live up to 35 years
  • Adult animals have about 10cm of insulating blubber under their skin
  • Seals' whiskers are so sensitive that they are able to pick up the shapes and sizes of their prey from the trails they leave in the water

According to the National Trust, between 1962 and 1983 approximately 2,000 adult females and 3,000 pups were shot.

Mr Steel explains that local fishermen "hated the seals". "They were still shooting small numbers until the 1990s," he tells BBC Nature.

But, as the fishing industry collapsed, it was gradually replaced by tourism. Today, several companies use fishing boats to take groups of people to visit the islands and admire the scenery, seabirds and, of course, the grey seals that make their homes in this bleakly beautiful place.

Follow that seal

Over the years, researchers have moved beyond monitoring the seal population to find out more about the animals.

Dr Bernie McConnell from the Sea Mammal Research Unit at Scotland's University of St Andrews has been studying the animals of the Farnes for 25 years.

He and his research team have worked on the islands for weeks at a time studying grey seal biology.

In one of their most recent projects, the team fitted adult seals with hi-tech data loggers that monitored the animals' movements. These tags glued on to the seals' fur and simply fell off when they moulted.

They work like mobile phones, explains Dr McConnell: "As soon as the seals come near shore, they phone their data home."

Warden marking a newborn seal pup with paint The National Trust wardens spray every pup with coloured paint, so they can count each newborn

This data includes location, which the tags measure via the GPA satellite system, and the depth the animal is at - measured via a pressure gauge.

"We can reconstruct the dive profiles of the animals," says Dr McConnell.

"They dive almost continually day and night; 80% of their time at sea is spent underwater.

We don't call them divers, we call them surfacers. Even though they're air-breathing mammals, just like us, that's where they spend the bulk of their time."

Part of the reason for tracking the seals in such detail is to ensure that their habitat is protected. The conservation status of the islands means they must be maintained in a way that is favourable for the seals.

"When they're at the Farnes, they forage within 50km of the [islands], but they're quite capable of travelling further afield," says Dr McConnell.

"There are boundaries to the protected areas and we've shown that the seals move way outside these boundaries.

We have to safeguard the food supply out in the North Sea... and allow them to complete their life cycle."

Grey seal with datalogger (Image: Bernie McConnell/ Sea Mammal Research Unit) Stick-on tags work like mobile phones, "phoning data home" when the animal comes near shore

The research also continues to reveal some of the remarkable ways in which these mammals have evolved to live in the water - withstanding huge pressures to dive up to 70m and using their super-sensitive whiskers to track the wake trails left by the fish they hunt.

And since seals are near the top of the food chain, they rely on a healthy marine environment to feed and survive.

"If the seal population is doing ok, it's one big indication that things are ok in their environment," says Dr McConnell.

"They're a window into the health of the seas."

Follow @BBCNature on Twitter

More on This Story

Related Stories

The BBC is not responsible for the content of external Internet sites

More from nature

  • Cardinal fish and ostracodFish filmed spitting 'fireworks'

    Film crew captures ostracods' spectacular defensive lightshow that makes predatory fish spit them out.

  • Arapaima'Locally extinct'

    A giant fish which used to dominate the Amazon river is now absent in many areas

  • DragonflyRapid reactions

    Dragonfly's super quick reactions recorded in slow motion by BBC film-makers

  • Wingless adult male of the midge Belgica antarcticaExtreme survivor

    Antarctic midge's small genome may be an adaptation to its extreme environment

  • Myotis midastactus specimen (previously identified as Myotis simus)Golden discovery

    A bat from Bolivia is described as a new species by scientists

  • Dinosaurs 'shrank' to become birds

    Huge meat-eating, land-living dinosaurs evolved into birds by constantly shrinking for over 50 million years, new research shows.

  • Would we starve without bees?

    Honey bees are under threat, and as pollination significantly contributes to the food we eat, what would we do without them?

  • Eggshells may act like 'sunblock'

    Birds' eggs show adaptations in pigment concentration and thickness to allow the right amount of sun for embryos, scientists say.

  • Female shrimps are more aggressive

    Female snapping shrimps are more aggressive than males when defending their territories despite their smaller claw size, a study shows.

BBC iWonder

  • Honey bee close-upInsect intelligence

    Are honey bees as smart as your sat nav?

  • Tyrannosaurus rex skull (c) Mark Williamson / Science Photo LibraryDinosaur dynasty

    One group of dinosaurs survived and their descendants can be seen all around us today

  • Brown rat cluse upRise of the rodent

    Reports of giant, 'super rats' are filling the headlines. But why are we being overrun by rats?

  • Cuckoo portraitHoliday hotspot

    What makes the UK such an attractive destination for visiting wildlife?

There have been 75 solar eclipses and 167 major volcanic eruptions in my lifetime

Nicole Malliotakis on Twitter comments on the events that have happened since she was born by using our personalised Your Life on Earth interactive infographic.

Things To Do


More Nature Activities >

BBC © 2014 The BBC is not responsible for the content of external sites. Read more.

This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.