For those looking to uncover the hidden wonders of the UK's wildlife, outdoor experts have revealed the eight rarest animals in the UK and the places you might be able to find them.

Searches for wildlife trails in the UK have increased by 3600% recently, according to outdoor experts Millets.

The experts said: "While we tend to associate the United Kingdom with its beautiful landscapes and historical landmarks, there is another extraordinary biodiversity that thrives within its borders – it’s rare and elusive animal inhabitants! 

"From majestic birds to secretive mammals, the UK is a place where amazing animals live.

"In the past, many of these species were commonly found in Britain, but due to environmental and other factors, their populations have sadly decreased."

With this in mind, Millets has come up with a list of the eight rarest wildlife species in the UK, along with where to find them and how they have come to be so rare. 

The 8 rarest animals in the UK and where to find them

From the Scottish Wildcat to the Turtle Dove, these are the eight rarest wildlife species in the UK according to the experts at Millets.

Red Squirrels 

The Herald: Red squirrels may be one of the UK's most well-known creatures, but they are also among the rarest.Red squirrels may be one of the UK's most well-known creatures, but they are also among the rarest. (Image: Getty Images)

Where to find them: Dumfries, Galloway, Northumberland, The Lake District, Isle of Wight 

Red squirrels are one of the UK’s most well-known creatures but also one of the rarest animals in the UK, according to the experts at Millets. 

The outdoor brand said: "Around 75% of red squirrels can be found in Scotland, particularly in the forests of Dumfries and Galloway.

"Once extremely common, there are only around 120,000 red squirrels left in the UK, compared to the whopping 2.5 million grey squirrels we have today."

Millets said there are several causes for the decline of red squirrels in the UK, most notably the competition from grey squirrels which were introduced from North America. 

If you spot a red squirrel in Scotland, you can report your sightings online to Saving Scotland’s Red Squirrels campaign

Capercaillie

The Herald: Capercaillies are large birds around the size of a turkey.Capercaillies are large birds around the size of a turkey. (Image: Getty Images)

Where to find them: Badenoch, Strathspey, Cairngorms National Park 

A Capercaillie is a large bird around the size of a turkey which can be found in the native pine forests of Scotland.

Capercaillie was extinct in the UK up until the 1830s before more were brought in from Sweden and reintroduced to Scotland.

But the bird is on the IUCN UK red list of threatened species with less than 2,000 remaining.

Sand Lizard 

The Herald: Sand Lizards are among the rarest reptiles in the UK.Sand Lizards are among the rarest reptiles in the UK. (Image: Getty Images)

Where to find them: Dorset, Hampshire, Surrey, West Sussex, Lancashire 

Sand Lizards are one of the rarest reptiles in the United Kingdom, according to the experts at Millets.

They are found on sand dunes and dry lowland heath but there are only a few colonies in the UK. 

Millets said: "In the 1970s, 39 sand lizards were released by scientists to see if they could survive in colder temperatures further north.

"Evidently, this experiment had some success as the colony of sand lizards still exists today."

The reptiles have also been introduced to other areas across the South of England, Lancashire, Wales and The Isle of Coll in Scotland.

Natterjack Toad 

The Herald: The Natterjack Toad is one of the largest amphibians in the UK.The Natterjack Toad is one of the largest amphibians in the UK. (Image: Getty Images)

Where to find them: Merseyside, Cumbria, Scottish Solway

The Natterjack toad is one of the UK’s rarest and largest amphibians, Millets said.

They are found along UK coasts because they prefer shallow water on sand dunes, healths and salt marshes, as warm water is needed for these toads to breed. 

The outdoor experts added: "They can be identified by a thin bold yellow stripe down the middle of their back and by the strange way they walk on their short legs instead of hopping.

"They are named for the males’ distinct cry which can be heard from up to a mile away during the Spring."

Pine Marten

The Herald: Pine Martins is part of a mammal family known as the mustelids which also includes the likes of weasels and otters.Pine Martins is part of a mammal family known as the mustelids which also includes the likes of weasels and otters. (Image: Getty Images)

Where to find them: The Scottish Highlands, Forest of Dean, New Forest 

Pine Martens belong to the family of mammals known as mustelids, which include weasels, otters, badgers, ferrets, minks and other similar species. 

Roughly the size of a domestic cat, these mammals have a long furry body, pointed fat and long bushy tails.

They can be identified by their dark brown fur and cream markings on the neck and chest, Millets explained.

The experts added: "Once the second most common carnivore in the UK, pine martens are now a rare and special sight."

Small Tortoiseshell Butterfly 

The Herald: The Small Tortoiseshell Butterfly is among the most common seen in the UK in spring and autumn.The Small Tortoiseshell Butterfly is among the most common seen in the UK in spring and autumn. (Image: Getty Images)

Where to find them: The majority of UK regions

While the Small Tortoiseshell Butterfly is one of the most common butterflies seen across the UK in spring and autumn, over the past few years, they have declined in numbers significantly, according to Millets.

The number of Small Tortoiseshell Butterflies has fallen by more than 75% since 1976 and conservation efforts are being made to create and maintain suitable habitats for them. 

Talking about the rare species, Millets said: "The distinctive black and orange markings on a Small Tortoiseshell Butterflies wings help them disguise themselves from predators, but it is also how they can be distinguished by wildlife spotters."

Scottish Wildcat

The Herald: The Scottish Wildcat, also known as the Highland Tiger, is one of the most elusive and rarest animals in the UK.The Scottish Wildcat, also known as the Highland Tiger, is one of the most elusive and rarest animals in the UK. (Image: Getty Images)

Where to find them: Scottish Highlands 

The Scottish Wildcat, also known as the Highland Tiger, is a critically endangered species native to the mountainous areas of Scotland.

It is one of the UK's most elusive and rarest animals, making encounters with these creatures incredibly rare, according to the experts at Millets.

These wildcats are primarily found in regions of the Scottish Highlands such as Cairngorms National Park and the Isle of Mull.

Millets said: "Sadly, Scottish Wildcats face several problems which result in a lower population, including deforestation, human interference and even hybridisation (where wildcats breed with domestic cats).

"Many conservation efforts are being made to protect and restore Scottish Wildcat habitats, including breeding programs, in hopes that this beautiful and unique species can be protected and cherished by future generations."

Turtle Dove 

The Herald: The turtle dove is a migratory bird that visits the UK in the summer months.The turtle dove is a migratory bird that visits the UK in the summer months. (Image: Getty Images)

Where to find them: East Anglia, Suffolk, South England

The Turtle Dove is a migratory bird that visits the United Kingdom during the summer months.

They are mostly found living in woodlands, hedgerows and farmland in the south and eastern regions of the UK and Wales, according to Millets.

Turtle Doves have become increasingly rare in the last few decades, despite once being a common site in the UK. 

Millets added: "Like many of the creatures on this list, turtle doves have suffered from losing their natural habitats.

"Intensive farming and the destruction of wildflowers have made nesting and breeding difficult for these peaceful birds."

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Turtle Doves are recognisable by their gentle purring call and soft grey-brown plumage.

They stand out from other similar species of birds thanks to the black and white striped patch on the side of their neck. 

If you spot any of these rare creatures in the UK, "be sure to keep a safe distance and don’t disturb them", the experts at Millets added.