Ecological use of Drones
By Adam Field
No doubt about it, drones are one of the technological leaps of the decade. They have become an industry in their own right and at the rate they are progressing, bring brilliant advantages to many fields. They do, however, have the potential for undesirable and potentially dangerous impacts if used incorrectly.
About 2 years ago, Ecology New Zealand toyed with the idea of using Drones in the ecology space and how they could be used to improve our services generally and across specialist works as well. These initial talks opened the floodgate for new thinking, and since buying the drone about 18 months ago, we haven’t yet been able to shut the gate. Starting with standard aerial photographs and videos, we quickly moved to purchasing software which enabled us to produce high resolution maps composed of multiple photos (30-1000+) taken top down by the drone. This was a game changer, allowing us to increase the accuracy of our assessments and presentability of our reports. Compared to satellite imagery, we were now able to complete a drone flight as part of our site visit which, once processed into a map, allowed us to identify current and correct landscape and ecological features such as vegetation composition and freshwater features. Though no substitute for ground-based assessments, the ability to map, measure and communicate our findings through a precise visual platform was hugely beneficial. If you’ve ever tried to distinguish between tree and shadow using satellite imagery, you’ll know this can have a big impact when aiming to quantify areas accurately etc.
Our UAV was deployed to map the current flow pathways before restoration work
The Drone being used to undertake vegetation mapping.
One of the biggest learning curves in our experience with drones is in the aviation space and how to ensure the drone is flown legally and safely at all times. Not surprisingly, there are rules for operating drones which, if followed, vastly reduce risks associated with their use. The general rules are fairly common sense such as not flying over property without landowner/occupier consent, keeping the drone in line of site, not flying at night etc, though as we’ve seen in the media recently, there are some that are still unaware or chose not to obey these rules. We decided early on to put our operators through drone pilot training recognised by the Civil Aviation Authority (CAA), which achieves a standard for competency flying the machine, but also educates pilots of airspace rules and how, if not followed, things can go wrong. This keeps our current operations safe, but of course we don’t want to stop here. We have recently applied for further certification with the CAA to enable us to undertake more exciting works utilising drone technology. Once achieved we will be able to undertake flights that relax some of the general rules including night flights, extended line of sight and herbicide application. With these in mind we will be looking to extend our services as far as our imagination, and new rules, will let us. We are currently focussing on pest plant control applications, particularly in hard to access areas such as cliffs or slip sites. We will also be investing in applications such as thermal imaging for mammalian monitoring. This will be explored across the spectrum, native and pest, for the likes of pest mapping (rabbits, goats, possums?) and also native monitoring for the likes of bats.
We welcome the continued review of flight regulations by the CAA, in particular the monitoring of drones through the likes of compulsory registration and new initiatives around policing unauthorised flights within controlled airspace.
We are excited to be part of this innovation wave, and within our own field hope to drive some ecological innovations of our own!
High-resolution mapping of this wetland allowed us to continue to monitor the recovery of this wetland.
Flow pathways can be clearly seen which may otherwise be missed in a standard site survey.
On a recent project, we used our drone to monitor the progress of restoration planting at a site in Manukau. The high-quality imagery enabled us to monitor the success of the existing plantings and identify weed species re-emerging across the site. From this, we were able to provide the client with a visual progress update, identify and quantify areas that required replacement planting and also assess pest plant maintenance requirements.
A similar project saw the use of the drone to survey the current vegetation community of a bush area. The high-resolution aerial imagery enabled the team to undertake a desktop assessment of the existing pest plant infestation and the extent of these. This map based assessment allowed for more accurate planning around labour requirements compared with the standard methodology of multiple team members walking the site, assessing requirements and working at the same time.