Andy Dodd, from the #GetOutside duo TwoTravlrs, takes us on a journey of discovery into how the use of drones could help with woodland management and wildlife conservation.
Towards the end of 2017, I decided to purchase a drone. I had been after one for a while, watching beautiful footage of the landscapes of our national parks appealing to the photographer in me, as well as the engineer in me and the aspect of fun that comes with controlling something in the air.
Having spent a while comparing makes and models and gathering advice from friends, I settled on the DJI Mavic Pro. Its controllability, image quality and small pack size (it folds up!), meant that I could take it out on our travels without much inconvenience at all. It has been packed into my bag on a number of walks and wild camps already, and usually ends up being thrown in the back of our van wherever we go.
A number - in fact all - of my family members took an immediate curiosity in the drone, after showing them its ability and image quality at a Christmas gathering.
Some expressed interest for aerial images of their houses, comparing past and present or to plan out renovations. Others suggested using it for making films of them in sports, or working in the outdoor industry.
I had bought it with some of this in mind already, and had expected some of these suggestions. But despite having a strong interest in photography, I hadn’t anticipated my grandparents coming up with so many ideas.
However, within a couple of days, my grandmother - a trustee of Bentley Wood - had put together an extensive list of possibilities of uses for the drone, which focused on woodland management.
Expanse of Bentley Wood
Bentley Wood lies along the Hampshire/Wiltshire border, due east of Salisbury, and covers an area larger than 1700 acres.
In 1985, having recently been purchased by a Charitable Trust, the Wood was designated a Site of Special Scientific Interest (SSSI) by Natural England, for the range of Lepidoptera (butterflies and moths) it supports. There are regularly 36 butterfly species recorded annually, with opportunities to see rarer species such as the purple emperor in certain months.
But it is species such as the pearl-bordered fritillary, small pearl-bordered fritillary, Duke of Burgundy and grizzled skipper that are of most conservation concern. The majority of these are traditionally found in woodland rides (linear trackway, designed for access) and clearings, with their decline in numbers throughout the UK being linked to the lack of management practices, such as coppicing (periodically cutting back trees and shrubs to stimulate growth) and formation of regular canopy gaps.
In Bentley Wood, a system of ride widening has been adopted so that a distinct woodland edge can be created, where a range of plants and insects (butterflies in particular), can flourish.
Unfortunately, this impact of these changes can very difficult to accurately assess and monitor from ground level. With many trees interlinking at the canopy, it can be difficult to identify the best trees to fell in order to create the correct size of canopy gap to help create the best environment for these rarer butterflies. This is where the drone comes in!
In only a few short months since the project’s conception, we've managed to:
- Document some of the clearings
- Spot what was thought to be storm damage (but later turned out to be caused by male deer showing it’s masculinity)
- Identify potential areas for a clear water pond (which greatly assists another local project)
- Film the majority of the large tracks through the Wood from above.
This has helped to provide clear detail of the canopy cover in areas where the butterflies are being encouraged to develop a base.
Aerial image showing tree species and spacing taking during the first flight
More often than not, the weather conditions can become a hindrance though. With fairly strong winds or imminent rain, we have been lucky enough to at least get a feel of what we could achieve with the use of new technology.
It was incredible to identify and see things in the woods from the view of the drone, which would have otherwise been impossible from the ground.
With spring just around the corner, great changes are expected to take place in the Wood, especially with respect to the light levels on the rides caused by leaf growth in the canopy.
Once leaves starting forming in the canopy, the next stage of the project will be able to start; repeating the flights we’ve already conducted and comparing the images. Placing winter and summer images side by side will allow us to easily identify areas which need to be thinned.
This will help to optimise the light conditions on the rides, and hence encourage some of the butterfly species that are of concern to thrive.
Over the next few months we may be able to monitor an array of other focus points as the leaves begin to grow, such as Ash dieback. Ash dieback is a canopy disease which is thought to be affecting the tops of some of the large Ash trees here.
This would usually be virtually impossible to access and assess, but with the drone, the trustees are able to analyse this in real time.
Aerial image of rides
Aerial image, trio of ponds
Until the spring has well and truly sprung, myself and the trustees of Bentley Wood will be waiting in anticipation of what more the drone can show us.
When that time comes, I’ll be posting a follow-up blog which aims to showcase the comparison between winter and summer, and any other interesting changes we manage to capture. Technology such as this has some incredible uses, and it’s really important that we support and explore these opportunities with open minds, just as the Bentley Wood trustees have.
Please note: this project is led by Bentley Wood. All drone photography is conducted with a trustee present, and permission to fly over the area by the owners, as is the law with any privately owned land.