Imagine, for a moment, that Britain  – the landmass and islands that make up England, Wales and Scotland  – suddenly vanished. Let’s set aside the unsettling apocalyptic imagery that conjures and focus on a very specific conservation question: if these islands vanished, what wildlife would be irreplaceably lost? 

This is when you realise that the overwhelming majority of our species are found elsewhere. Our species of badger is found across most of Europe. The pedunculate or ‘English’ oak is found across all of Europe and into Asia. The golden eagle is found all the way around the Northern Hemisphere. The robin that sings in your garden, the beech that spreads its branches across your local park, the otter that slips into a river – these are all species that can be found far beyond our borders. If Britain disappeared tomorrow, most of the species that live here would persist elsewhere. 

What is ours alone?

What do we have that is globally irreplaceable? It’s a question that I explore in my new book, Endemic, which is devoted entirely to the stories of Britain’s unique species. After much reading and research, I have come up with a list of around 700 species found nowhere else in the world. That figure breaks down into: 

• 641 plants 
   
• 33 lichens 
   
• 22 invertebrates 
   
• 5 mosses 
   
• 1 liverwort 
   
• and (perhaps) a single vertebrate; a bird 

A few of these species, such as the orange-striped stonefly  – a stout, colourful, modern representative of an ancient lineage which is found on clean, fast-flowing rivers  – are quite widespread in Britain. On the whole, though, the majority of our endemics are quite rare and localised. 

Let’s take a look at the Lundy cabbage. First, banish the mental image of a typical cabbage from your mind. This isn’t a neat globe of leaves and is instead a gangly, yellow-flowered plant. It is known only from around a 3km length of the eastern cliffs of Lundy Island, off the coast of Devon, and has never been found anywhere else on the planet. The Lundy cabbage is also the foodplant of a beetle – the Lundy Island flea beetle, known only from this plant on Lundy. This is the only example in Britain we have of co-endemism; an endemic species that lives on another endemic species.  

Also in Devon, there is the British false flat-backed millipede, known only from around 10km of the English Channel coast. I tracked it down in December 2023 and took what turned out to be the first ever photo of this species. 

That took me by surprise; how is that a species that we in Britain have total, global responsibility for has never been photographed? But then a lot of our endemic species seem neglected or overlooked. Some of them haven’t been seen in years.  

• The dance-fly Poecilobothrus majesticus was discovered in Essex in 1907 but hasn’t been found in over a century
• The Caledonian planthopper, Cixius caledonicus, hasn’t been seen for 70 years
• The Manx shearwater flea hasn’t been seen since 1966
• There have been no records of Ivell’s sea anemone since 1983

Wonders at local Wildlife Trusts

Thankfully, many of our endemic species are much better understood than this and, although often rare, are safeguarded on nature reserves, including many managed by The Wildlife Trusts. 

One striking example is the false-toothed lady’s mantle. Lady’s mantles are enchanting plants, their heptagonal leaves edged with fine teeth, catching dewdrops like jewels. Britain has several species, and in recent years taxonomists have begun to look more closely at them, teasing apart taxonomic complexities to reveal new species. In 2021, the false-toothed lady’s mantle was formally recognised as its own distinct species, though it had first been spotted as long ago as 1958. 

What makes this plant extraordinary is its rarity. It has only ever been found in a single Yorkshire Wildlife Trust nature reserve, Grass Wood in the Yorkshire Dales. For this species, the Yorkshire Wildlife Trust carries a responsibility that extends far beyond county or country. It bears the rare and weighty task of safeguarding the very survival of a flower found nowhere else on Earth. 

Another example is the Menai Strait whitebeam, Sorbus arvonicola, a small tree that grows on the Caernarvonshire coast, gazing out across the water towards Anglesey. There are only a little over thirty of these trees in existence in the entire world. They are classed as Critically Endangered; threatened by sea-level rise which gnaws at the low muddy cliffs the whitebeam grows on.

When I went to see them the fragility of their situation was clear. The slopes they grow on are unstable, eroding quickly, and I found one tree that had recently collapsed onto the narrow beach. Yet here is a species that has evolved to exist in precisely this slender margin between land and sea. The majority of the world’s population is found on the North Wales Wildlife Trust’s Nantporth Nature Reserve. That means this single reserve holds near-global responsibility for the survival of the species.

And there are more examples, particularly of our endemic whitebeams. The round-leaved whitebeam, while more widespread than many of its endemic cousins, is still confined to scattered sites across southern Britain, including the Avon Wildlife Trust’s Goblin Combe reserve in Somerset. The Symonds Yat whitebeam, Sorbus saxicola, a tree with only a few dozen individuals known, can be found around Herefordshire Wildlife Trust’s King Arthur’s Cave, and the Herefordshire Whitebeam, with a little over a hundred known trees, can be found at their Miner’s Rest reserve. 

At College Lake Nature Reserve, the Berks, Bucks and Oxon Wildlife Trust maintains an arable plant collection that includes the endemic interrupted brome, a grass species twice-extinct in the wild, but now conserved and grown here.  

Meanwhile, in the ever-evolving field of elm taxonomy, more than 50 endemic elms have been proposed. Brian Eversham, CEO of the Beds, Cambs and Northants Wildlife Trust, has been a leading voice in clarifying our understanding of this group, even producing a field guide to their identification. The Wildlife Trust’s Hayley Wood reserve is home to the endemic Hayley elm, along with several other endemic elm species. 

These examples reveal something; Wildlife Trusts are not just protecting local biodiversity for local people. In some cases, they are the only organisations on the planet standing between an entire species and extinction. 

What would be lost?

When I set out to write Endemic, this was the story I wanted to tell: that our young islands hold a global conservation responsibility. We may not have the dazzling array of endemics that older, more isolated islands boast, but the species we do have – some overlooked, some critically endangered, some clinging to single reserves – are ours alone. 

In the end, when we ask ‘what would be lost if Britain vanished?’ the answer is these 700-or-so endemics. They are the species that make nature in Britain truly unique. We need to notice them, celebrate them, photograph them, conserve them and share their stories. For if we fail to do so, we risk losing not only these plants, animals, lichens, and bryophytes, but also the very essence of what makes Britain unlike anywhere else on Earth. 

James Harding-Morris is a passionate nature enthusiast with a lifelong love for exploring the natural world. Currently, James is on a mission to ensure that everyone in Britain and Ireland has the opportunity to fall in love with plants through his work with the BSBI.

You can purchase a copy of his book Endemic; Exploring the wildlife unique to Britain via the Bloomsbury website.