It is in these waters sluicing through the Cairngorms that a particularly prized part of the environment exists: freshwater pearl mussels, which are among the planet’s most critically endangered creatures. The jewels in the mussels are rare – about one in 5,000 contains these milky-white treasures – and, as such, they have historically been valued. According to Julius Caesar’s imperial biographer, Suetonius, the leader was an obsessive pearl connoisseur who allegedly had the Roman army invade Britain in 55 BCE in part because of these iridescent gems. Appropriately, the Crown of Scotland – the oldest piece of crown jewellery, dating to 1540 and including materials from an even older diadem – features pearls from these molluscs.
“The funny thing about pearl mussels, if you ask anyone in Scotland, most of them don’t know they exist,” said Annie Armstrong, founder of nature tourism company Wild Braemar that organises excursions for Fife Arms guests. “They’re kind of this secret, unknown thing.”
Today, these imperilled mussels are on the verge of extinction – a particularly troubling reality given that they’re a keystone species. A single mussel filters 50 litres of water a day and their presence indicates good water quality; if they are at risk, it’s a harbinger of a decline in the river’s health. Scotland has always been a stronghold for the species, which can live up to 100 years, and their presence in the Dee has led the river to be granted a Special Area of Conservation designation.
Despite a ban on pearl fishing or buying and selling Scottish pearls since 1998, poachers still stealthily try their luck. There’s a more daunting adversary, though: warming waters caused by climate change and exacerbated by a lack of tree coverage that would help mitigate rising temperatures.
