Unmanned aerial vehicles (UAVs), or drones, are a useful tool in wildlife conservation, performing duties ranging from anti-poaching to crocodile and bird counting.
Dr Debbie Jewitt from KZN Ezemvelo Wildlife gave an overview of her organisation’s use of UAVs during the Drones Conference 2018 at Emperor’s Palace last week.
She said that UAVs are proving to be extremely beneficial, especially in places that people can’t reach; in places that are dangerous and where efficiency is needed.
UAVs provide very good resolution images compared to other tools like satellites – for instance the Airbus Spot 6 satellite has a resolution of 1.5 metres whereas the Albris UAV has a resolution of 1 cm, giving far superior detail. They are also substantially cheaper than manned aircraft and can carry a variety of sensors, from thermal to optical.
Jewitt emphasised the fact that UAVs are used for far more than just anti-poaching missions – for instance they are used for land mapping and surveying including tasks such as evaluating erosion, assessing the effects of herbicide spraying, evaluating fire damage, mapping alien plants, and identifying different plant types and tree mortality.
UAVs have been very successfully used for wildlife counting – for instance counting the nests of Cape vultures. Before, researchers would try and count the nests from the ground, but by flying alongside cliffs with a UAV, far more nests can be seen. As a result, the vulture population estimates became far more accurate – for example, traditional methods in one case estimated under 40 nests while a UAV survey revealed over 90. Similarly, traditional counting methods in one study estimated the Cape Vulture population to be 120 but a UAV survey in 2017 revealed it to be 200.
Game counting is another application for UAVs, but Jewitt said it is best for small herds as it is not the most efficient for large herds. It is also very useful for bird counts, as birds nesting on top of trees can be identified, giving accurate statistics. Likewise, crocodile counts and nest detection have become more accurate using UAVs, with a 26% increase in the number of crocodiles counted by UAVs.
UAVs can also be used to determine the age of animals – for example, by applying software to measure the height of elephant shoulder bones, their age can be determined.
It is not just on land that UAVs can be used for monitoring wildlife – the National Aeronautics and Space Administration (NASA) developed an ocean monitoring technique called fluid lensing. Researchers realised that as a swell passes over the shore, it magnifies the area underneath it, and by applying fluid lensing techniques to littoral areas, it is possible to generate remarkably clear pictures of what is under the surface of the water – for instance coral, sea cucumbers, fish and sharks can easily be identified.
Another application KZN Ezemvelo Wildlife has used UAVs for is search and rescue, and has done successful trials in the Drakensberg using Mavic, Phantom and Matrice UAVs.
UAVs are much safer for users compared to manned aircraft, as manned aircraft when used for environmental purposes are generally flown low, resulting in a relatively high number of accidents. Jewitt said that 66% of deaths of people involved in the wildlife industry are due to air crashes, and UAVs could greatly decrease this statistic.
One potential problem with using UAVs is disturbing wildlife, as flying too close to animals can startle them. Birds of prey do not like UAVs and regularly attack and damage or even destroy smaller aircraft. Elephants do not like UAVs as they sound like bees, but this has actually been turned into an advantage to chase elephants away – they can be a major nuisance when destroying crops, for instance.
Other drawbacks Jewitt highlighted include difficulty in recovering UAVs, technical problems, wind intolerance, short battery life, and inability to cope with extreme temperatures – for instance most UAV batteries do not work well in sub-zero or extremely high temperatures. Legislation is another major hurdle, as the South African Civil Aviation Authority (SACAA) requires commercial operators to have an air operator certificate, which treats UAVs like airliners and is a major hindrance. In addition, the National Environmental Management Act prohibits UAVs, and other aircraft, from flying below 2 500 feet without permission.
UAVs are not widely used in South Africa’s national parks for anti-poaching activities. Jewitt said trials have not been particularly successful mainly because of the poor response time but she does not rule out using the technology as it develops and improves in the future.
In 2015/16, UAV anti-poaching trials were conducted in the Kruger National Park, Hluhluwe Imfolozi Park in February and at Manyeleti game reserve. Small fixed wing aircraft were used with commercial off the shelf sensors, but results were not as good as hoped due to long deployment times, susceptibility to the weather, poor sensors and limited stealth.
After the tests the Council for Scientific and Industrial Research (CSIR) concluded that unmanned aerial vehicles can be successfully used in counter-poaching operations given the right sensor fit, but to date the technology has not been adopted by South African National Parks (SANParks). However, industry players have noted that sensor and airframe technology has improved tremendously since then and SANParks officials have said they are willing to reconsider using UAVs for anti-poaching as capabilities improve.
Although conservation officials are not widely using UAVs for anti-poaching, poachers are increasingly adopting the technology. Jewitt said it was an alarming trend that poachers are using UAVs to assist them find and kill animals.