One of our dedicated readers asked us if drones could really be used for wildlife population estimates. Here is a detailed question:
I am in the middle of conducting population estimates in the Texas Hill Country with focus on white-tailed deer and horned lizards. Can you please share with me a drone capable of carrying out autonomous flights and capturing infrared aerial imagery?
This could be a magnificent use of a drone. The wildlife arena has seen a rapid increase in integration of infrared cameras into drones not only for conducting population estimates but also for identifying poachers and hunt down hogs (an effort to cease invasive species).
We are no experts in the use of drones for population estimates so we contacted Jeff Jackson, a senior Wildlife Enforcement Officer with the Nisqually Indian Tribe in western Washington State. He has been flying a DJI Inspire 1, Version 2.0 with the Zenmuse X3, Zenmuse Z3 and FLIR cameras and he has been carrying out surveys related to the pillage of salmon in the south Puget Sound.
The first thing to take into account is the fact that the approach needed to estimate the population of deer is going to be entirely different from that required to estimate lizard’s population. And, hey, estimating the population of a creature as small as a lizard could be extremely taxing.
Jackson says that deer pose a nice and large enough target with a body temperature that is in contrast to the surrounding environmental conditions. He believes that early in the morning or cooler days could be the appropriate time for the best thermal difference between the background and the animal. He adds that it could be difficult to spot these creatures during the day with just a visual camera but FLIR cameras can make the difference even in the daylight.
He articulates that lizards are way harder to capture not only because of their smaller size but also because of their body temperature.
Jackson opines that lizards are cold blooded creatures with a body temperature close to ambient air temperature with low variation.
Drone equipment required
Jackson prefers DJI equipment which comes up as no surprise owing to the tech giant’s massive 74% share in the drone industry. DJI has numerous drone series such as the Phantom, Inspire, Matrice and all of these can be used to estimate wildlife population.
DJI Inspire Series
Jackson strongly recommends the DJI Inspire series purely because they offer a wide array of alternatives at an affordable price. He thinks of DJI Inspire 1, version 2.0 as an efficient beast without the cost of the Matrice platform.
A thermal camera is mandatory and FLIR is the way to go. FLIR cameras are compatible with DJI products and it is a far better option than mounting a third party thermal camera to a drone and having to view the video footage later.
Jackson adds that the FLIR camera lets him figure out the size and heat signature when a visual count is not possible for a variety of reasons.
DJI Matrice Series
The Zenmuse XT2 thermal imaging camera, created by DJI in collaboration with FLIR, is a brilliant reason to purchase DJI Matrice series at a higher price instead of the affordable DJI Inspire line. The Zenmuse XT2 is an enhanced version of the older Zenmuse XT which was an infrared camera engineered to be integrated into DJI drones by incorporating not only an infrared camera but a dual sensor to show a conventional 4K UHD video feed in real time. The XT2 can be attached to any M200 Series drone as well as the Matrice 600 Pro.
The camera has been designed for drone pilots who aim to capture heat signature invisible to the naked eye. It comes with a stabilizing gimbal and incorporates the current DJI features; thereby letting the pilots use the DJI’s current flight modes such as QuickTrack, which focuses the camera on a particular target. The HeatTrack automatically focusses the camera on the hottest object in the view. The DJI Zenmuse XT2 is loaded with a 12MP visual camera and is available in a couple of thermal sensor resolutions of 640 x 512 or 336 x 256, with 9mm, 13mm, 19mm and 25mm lenses. It is supported by M200 Series drone as well as the Matrice 600 Pro enterprise drones.
Options other than DJI
Yuneec can be a reliable alternative to DJI with their Typhoon H Plus with Intel RealSense. The drones comes with a 6 rotor architecture, omnidirectional, triple axis gimbal with foldable landing gear and CGOET dual thermal RGB camera.
Here are a few things to remember:
- Go for spare batteries to extend your flight time since DJI Inspire 1 only offers an 18 minute air time (Jackson owns 8 extra batteries)
- Opt for a drone with dual remote controllers so one can fly the drone and the other partner can solely focus on the camera to get the wildlife count
- Choose a camera with zoom in and out options. This will let you visually zoom in for a count without scaring the creature away