A new book offers an insight into how many non-native species – from rabbits to rhododendrons, mink to muntjac – have become established on our shores. Ross Bentley talks to author Dan Eatherley about his latest work.

East Anglian Daily Times: Grey squirrel Picture: Kevin SawfordGrey squirrel Picture: Kevin Sawford (Image: Archant)

Author Dan Eatherley got the idea for his new book after taking a stroll through London's Hampstead Heath and being struck by how much around him wasn't 'natural' in the sense that it didn't represent British fauna and flora.

He saw rose-ringed parakeets, grey squirrels, Canada geese, mandarin ducks, horse-chestnut trees and rhododendrons, while in a pond there was carp - all species that originated elsewhere but which today have established themselves on our shores.

It set him on a path of painstaking research about the history of plant and animal invaders to the British Isles - a tale spanning thousands of years, entertainingly told in his wonderful book Invasive Aliens, due to be published later this month.

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Negative impacts

East Anglian Daily Times: Spring blooming Rhododendrons at Minsmere. Picture Val BondSpring blooming Rhododendrons at Minsmere. Picture Val Bond (Image: (c) copyright citizenside.com)

Mr Eatherley's work covers the earliest settlements of our islands, through Roman and medieval times and the age of exploration by Europeans, to the current period of global trade, where new species are arriving in ever greater numbers. Today, there are estimated to be over 3,000 non-native flora and fauna in England, Scotland and Wales, of which almost 2,000 - mostly plants - have established and are reproducing in the wild. It has been calculated that at least 275 (9%) are causing negative impacts, such as crowding out native species or spreading pathogens.

There is much here that is eye-opening and connections with East Anglia abound. For me, it was news that the rabbit, a species that has done so much to shape the sandy landscape of the Brecks, was brought over by the Romans and then established further by Norman rulers. It was also the Normans who were instrumental in settling the fallow deer, originally from southwest Asia, as they set up deer parks. Today, the fallow deer is an honorary native, widespread in the east of England and Britain's most common deer.

Exotic species

It is another species of deer, the Reeves muntjac, that brings Mr Eatherley to Thetford Forest and an account of spotting this dog-sized ruminant on the Suffolk-Norfolk border - one of a number of personal encounters to be found in his book. This primitive woodland deer, originating from China, was brought to the UK in the late-nineteenth century by Herbrand Arthur Russell, the 11th Duke of Bedford, who was looking for exotic animals to inhabit his 1,200 acre deer park at Woburn Abbey. The deer soon broke beyond the borders of the park while translocations, including an introduction at Norfolk's Elveden Estate, also helped it spread. Nowadays, it is a common sight across East Anglia, its ability to reproduce all year round a key reason for its success.

Incidentally, Herbrand was also instrumental in introducing the grey squirrel after importing ten animals from New Jersey to Woburn in the 1890s.

For me, this Victorian period is fascinating and Eatherley introduces us to many of the characters of the day. It was a time when the East India Company was expanding its influence across the globe and colonisers were exporting British species abroad to make their new territories feel more like home. Exotic species were also travelling in the opposite direction to the UK to satisfy wealthy collectors with a zoological bent and natural history enthusiasts who wanted to 'improve' the local wildlife offering - an approach known then as acclimatisation.

East Anglian Daily Times: Fallow deer Picture; Getty Images/HotHibiscusFallow deer Picture; Getty Images/HotHibiscus (Image: HotHibiscus)

Arrogance

"The mind-set at the time was one of progress," Mr Eatherley tells me when we speak on the phone.

"But there was an arrogance there, an assumption that we own the world and we can improve it. There was a feeling that nature was found wanting."

As well as animals, plant hunting became a popular practice that brought in invasive flora such as rhododendron, giant hogweed, Japenese knotweed and Himalayan balsam - species that in succeeding years have overrun our native landscapes and remain a concern for conservationists.

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East Anglian Daily Times: Dan Eatherley Picture: Ross GillDan Eatherley Picture: Ross Gill (Image: Archant)

Horticulture

These were different times but despite all we know now about the folly of introducing species, it still goes on today.

"Everyone seems to realise that it is not a good idea to bring in animals anymore but the importation of plants continues," said Mr Eatherley, an environmental consultant when away from the keyboard.

"Horticulture is the modern version of acclimatisation and many of us still buy imported plants to improve our gardens."

With conservation groups giving more and more time to dealing with the impact of invasive species, Mr Eatherley's work is timely. But why is there this focus at this moment?

He dismisses suggestions it may be a xenophobic reaction related to Brexit as "too simplistic". -

East Anglian Daily Times: Invasive Aliens coverInvasive Aliens cover (Image: Archant)

He adds: " Many people today feel a sense of responsibility for our ecosystem and belatedly are realising how much we have messed it up - by going out and pulling up some Himalayan balsam they feel they are doing something to help."

n Invasive Aliens by Dan Eatherley is published by William Collins and costs £16.99. It is due out on June 27th.