What does the future hold for deer in English woodlands? And what can we learn from Scotland, Wales, and Northern Ireland?

MOST counties in England harbour at least three species of wild deer, a radically different scenario from the Middle Ages when there were few free-roaming ones. 

Red (Cervus elaphus) and roe (Capreolus capreolus) are true Brits; fallow (Dama dama) are honorary natives; sika (Cervus nippon) and muntjac (Muntiacus reevesi) are well-established aliens; and Chinese water deer (Hydropotes inermis) are quickly getting a hoof-hold.

Although reds are often associated with the now denuded uplands or ‘The Hill’ in the UK, we tend to overlook that across much of their natural continental European range they are forest dwellers. 

The UK’s deer population is at its highest level for 1,000 years and numbers may have doubled since the turn of this century. Many people are obsessed with exactly how many of these creatures there are. Woodland deer are notoriously fickle to tally accurately; most counts are underestimated several fold. Yet precise stats are not essential for sustainable woodland management.

That said, best working guesstimates hover around 3 million. A proportion are reds and roe in Scotland – perhaps over a million. What is certain is that both the overall numbers and their distribution are on the up. 

Hazel coppice stunted by browsing. (Image: FJ)

Although natural deaths and road-traffic accidents at up to 75,000 a year take their toll, if uncontrolled deer stocks can increase by almost a third per annum – and the growth is exponential. Culling only males will not shrink the populations either. 

In the last few years, my own small woods in north Bucks have witnessed the arrival of Chinese water, roe and red deer to rub shoulders with the resident muntjac and fallow. 

In late winter and early spring, when conditions are tough, fallow may congregate in large troops – but I was taken aback last winter by a Twitter clip of a column of 900 (yes, 900!) crossing open fields between two woodlands in Northamptonshire, and drone footage of 1,500 together in Leicestershire.

THE WOODLANDS 

The National Forestry Inventory (2020) provides a record of the size, distribution and key attributes of forests and woodlands in Great Britain. It defines ‘woodland’ as a minimum area of 0.5 hectares under stands of trees with, or with the potential to achieve, tree crown cover of over 20 per cent. Areas of young trees with the potential to achieve this are included. Such woodlands clothe around 3.2 million hectares or 13.2 per cent of the UK. Around 1.29 million hectares are in England, of which a third is in private ownership. 

Although there are some owners or custodians of extensive lowland woodlands, such as Forest England or the National Trust or private estates, there is a mish-mash of thousands of other holders of smaller parcels. Of all woodlands in England, 69 per cent qualify as small, with 41 per cent under 20 ha. Roughly half is dominated by native species, yet only seven per cent is in optimum or good ecological condition. Adverse factors include lack of active management and too many deer.

Since the turn of this century, hobby woodlands or family forests have flourished, with larger woodland blocks split into multiple parcels of just a few acres and sold at mouth-watering prices. For many of the new breed of owners, glimpsing wild deer on their micro-holdings is a huge bonus.

WHAT ARE THE ISSUES? 

Woodland is an ideal habitat for deer and one they can severely impact if numbers are too great. A graphic, must-see, time-lapse example of the before-and-after impact of these animals on one woodland ecosystem is on a recent Forestry Commission blog (2022a). Many readers of Forestry Journal will be all too familiar with what deer may get up to in the woods and adjoining land through trampling, debarking trees, males marking territories and selective feeding. 

The effects of grazing and browsing may not be so obvious to the untrained eye as in debarking or fraying young saplings, but can be far reaching over time.

With an adult fallow consuming around 5 kg of fresh green plant material a day, that equates to 100 eating 182 tonnes/annum, equivalent to the intake of 15 cattle or 100 sheep. And to top that, most deer are highly selective feeders in woodlands, taking the most nutritious morsels and leaving less palatable species such as bracken and coarse grasses, which then flourish.

Persistent browsing can result in bonsai or topiary trees, browse lines and impoverished ground flora. Deer can suppress natural regeneration by nipping off or uprooting the emerging seedlings and hoovering acorns.  

If growing tall trees is the aim in new woodland plantings, human intervention may be required. Otherwise, ongoing browsing can transform future carbon-sequestering trees into shrubs – a valuable wildlife habitat nevertheless. 

These wild animals are the number-one challenge for coppice workers who need to fence off coupes or erect dead hedges to keep deer from nibbling off the fresh, succulent regrowth. 

In the overall balance sheet of commercial losses and gains, is deer damage really a significant drain? Are they just a scapegoat for foresters’ and farmers’ frustrations? Or are they an inevitable write-off? Are any losses really economic or just aesthetic?

To get an idea of the scale, Forestry and Land Scotland calculated the losses caused by these ungulates to young plantations and other commercial woodlands north of the border is £3 million a year. According to DEFRA, losses to farm crops weigh in at £4.3 million annually, with the greatest harm to cereal crops in east and south-west England.

Yet harm can be environmental too, which is far more challenging to put a figure on, particularly in an age when values are put on natural capital, ecosystem services or carbon credits. How do you calculate the loss of say nationally rare oxlips or classic bluebells in a woodland that is a Site of Special Scientific Interest (SSSI), where deer have run amok? 

CONSERVATION CONCERNS

Whole lowland woodland ecosystems can suffer at the mouths and hooves of wild deer. Recent times have seen a marked rethink in the way many conservation bodies view an overabundance of these animals as unwelcome guests.

Flowering perennial woodland ground plants are special favourites; as deer feast on them each spring, that vegetation succumbs and the associated wildlife suffers. The woodland structure changes too, with less ground cover and sparse natural tree regeneration.

Woodland impacted by deer – devoid of understorey and dominated by coarse grasses (picture courtesy of Steve Scott). (Image: FJ)

Natural England worries the detrimental effects of these creatures in SSSIs – the jewels in the woodland ecosystem crown – is impoverishing them. The area of such woodland currently in ‘unfavourable’ or ‘recovering’ condition due to deer is put at 8,000 ha. This is likely to represent a fraction of the real picture.

British Trust for Ornithology studies have shown how high deer stocks can have a negative knock-on effect on many species of woodland birds and hasten their downward spiral of browsing, while grazing may indeed be beneficial to other species. 

Less is heard about bringing back existing, neglected woodlands into an optimal state – and that often means curtailing cervid activities. Only half the UK’s current woodlands are actively managed; that leaves 600,000 ha that are not. 

MANAGEMENT OPTIONS 

Management regimes adopted will depend on the end goal of planting additional lowland woods or optimising or extending present ones.
What is crucial to alleviate any adverse effects is to monitor trends to determine if whatever measures adopted to curb impacts on the treed environment are working – or not.

If there is a real and pressing need to curtail the unwanted effects of these animals in many lowland woodlands, how do land managers go about mitigation?

We’ll investigate further and take a look at potential strategies in the November issue of Forestry Journal.