Wild and wintry weather was tearing across the flat North Lincolnshire landscape, showering the huge ploughed fields and ruler-straight roads with whirling leaves and bursts of rain. Lovely weather for ducks – and for grey seals, according to Claire Weaver, Natural England’s adviser on wildlife management for several of the Sites of Special Scientific Interest along the Lincolnshire coast. ‘The seals don’t care,’ she observed as we set off along the fenced path through the dunes of Donna Nook, heads down against wind and rain. ‘They’ve got just two things on their minds at this time of year – giving birth, and having sex.’
The UK is home to something approaching half the world population of grey seals, and the window of opportunity for them to pup and mate is a narrow one. They have to come ashore to do both, explained Claire. But on land they are slow, clumsy and vulnerable, particularly when all hyped up and distracted by birth and sex hormones. So nature squeezes both activities into a very tight time frame. The cows, having delayed implantation of last year’s fertilised egg for seven months, have been carrying developing pups since late spring. They give birth a couple of days after they reach land, wean their pup for three weeks, and then mate and get back to sea in as short order as possible. By that time they are literally starving; they don’t eat while on shore, and drop about 40% of their body weight.
The enormous flat expanse of salt marsh and mud flats at Donna Nook on the southernmost edge of the Humber Estuary, the Lincolnshire grey seals’ chosen pupping and mating ground, is not only an SSSI and a National Nature Reserve managed by Lincolnshire Wildlife Trust – it’s also an MoD bombing range. Juggling things so that aircraft can practice, seals can perform their functions undisturbed and the public can enjoy the spectacle safely is a complicated business, but NNR warden Rob Scott, his solo assistant and dozens of volunteers make a wonderful job of it. The fenced path conducts you along the edge of the saltmarsh, and there are the seals, hundreds of them, some close enough to touch – if you don’t value your fingers. ‘They’re wild animals,’ Claire reminded me as we stood looking down at a snow-white pup cuddled up to the fence, ‘and they can give a nasty bite.’
There is something very Walt Disney about grey seals – the adorable huge-eyed pups in white coats, the sleekly dappled mothers and big bruiser males with ripples of fat round their scarred necks. ‘Ooohs’ and ‘Aaahs’ were in the air. At first glance all the adults looked utterly docile, a collection of fat slippery slugs marooned in the mud. But nature is a ruthless driver of behaviour. The bulls went slithering and undulating forward to confront one another with open-mouthed roars, occasionally tumbling over in actual combat as they bit at one another’s necks. Young males not yet bulky enough to ring-fence a harem made nuisances of themselves, teasing the seniors by invading their personal space to provoke deep roars and impressive displays of sharp teeth.
A couple of bulls tried their luck with the cows, but were warned off with snarls. It was a little early in the season for mating; the first pups had only been born three weeks before. Now there were well over four hundred of them, ranging from the newly born (in coats still stained bright yellow by amniotic fluid) to three-week pups already losing their lanugo or baby coat of white.
The cow and pup pairs lay high up the salt marsh or in the dunes, well away from the roaring and splashing on the mud flats. I watched a well-grown pup nuzzling for its mother’s tiny teat while she guided it with flaps of her flipper. Seal milk is fabulously rich in fat, so while the cows and bulls starve and diminish, the pups put on weight like super-sizers, nearly four pounds a day. ‘They need to,’ said Claire. ‘When that cow goes to mate and then back to sea, the pup’ll be fending for itself for the next fortnight, living on its blubber until it gets into the sea and starts fishing for itself.’
It was a mesmerising sight – the rain-freckled marsh and mud flats covered in grey seals, apparently inert, in reality working overtime to respond to the timeless imperative of reproduction of the species. As I watched, I became aware of the extraordinary noise the seals were making, swelling like a chorus behind the show – a mooing, roaring, groaning and banshee wailing that our seafaring ancestors told each other was the song of the mermaids. Eerie, ghostly and spine-tingling, it haunted my inner ear for the rest of the day.
Seal-watching at Donna Nook NNR: A1031 (Cleethorpes-Mablethorpe) to North Somercotes; brown signs to Donna Nook. Open to public (free) all year. Best time is pupping season, mid October – late December. Observe MoD range warnings. Try to visit on weekdays; weekends get very crowded, lanes are narrow and car parking limited).
Claire Weaver’s seal-watching hints
Don’t get too close – you will disturb the seals, cows might desert pups, and you could get badly bitten.
At Donna Nook, keep out of the sanctuary area.
They’re wild animals – don’t feed or pet them.
Leave the dog at home.
Bring your binoculars, and don’t forget the camera
Help and advice
The Wildlife Trusts (01636-677711; www.wildlifetrusts.org) co-ordinate 47 local Wildlife Trusts across the UK, Isle of Man and Alderney, and should be able to help you locate and watch grey seals. Other helpful agencies are Natural England (0845-600-3078; www.naturalengland.org.uk), Scottish Natural Heritage (01738-444177; www.snh.org.uk), Countryside Council for Wales (0845-130-6229; www.ccw.gov.uk) and Northern Ireland Environment Agency (www.ni-environment.gov.uk).
Grey Seal information: http://www.pinnipeds.org/species/grey.htm;
Grey seals in Wales: http://www.welshwildlife.org/Greyseals_en.link
Accommodation: West View B&B, South View Lane, South Cockerington, Louth, Lincs (01507-327209; www.west-view.co.uk). Very helpful and friendly.
Reading: Seals by Sheila Anderson (Whittet Books)
Information: Donna Nook NNR (01507-526667; www.lincstrust.org.uk)
Louth TIC: Cornmarket, Louth (01507-609289; www.visitlincolnshire.com)