In the world of ecology, understanding and monitoring wildlife and their habitats is crucial for conservation and research. Traditional methods have served ecologists well, but they often come with limitations, such as the difficulty of observing nocturnal animals or those that are camouflaged. Enter thermal imaging – a cutting-edge technology revolutionising ecological studies. Night vision aids (NVAs), which include thermal and infra-red, are now recommended for use in emergence surveys by the Bat Conservation Trust in their Guidance for Professionals.
In this blog, we will explore how thermal imaging works and its applications in ecology, with some examples showcasing its potential. Whether you are a seasoned ecologist looking to incorporate thermal into your surveys or are simply interested in wildlife monitoring, this introduction will help you figure out which thermal imager is best for you.
How does thermal imaging work?
Thermal imaging cameras detect infrared radiation – a type of energy emitted by all objects with a temperature above absolute zero. Unlike visible light, infrared radiation is invisible to the human eye but can be captured by specialised sensors in thermal cameras. These sensors convert infrared radiation into electrical signals, which are then processed to create a visual image. The resulting images display temperature variations in different colours, making it easy to identify warm animals, temperature gradients in vegetation, and even hidden nests, dens or roosts.
Why use thermal?
Thermal imaging technology offers several unique benefits that make it an invaluable tool for ecological surveying, and has some key benefits over other night vision aids.
Use in All Light Conditions
One of the most significant advantages of thermal imaging is its ability to function effectively in all light conditions. Unlike traditional cameras that rely on visible light, thermal cameras detect infrared radiation, which means they can capture images regardless of lighting. Whether it's day or night, cloudy or clear, thermal imaging provides consistent and reliable data.
Non-Intrusive
Thermal imaging is a non-intrusive technique, allowing ecologists to observe wildlife without disturbing their natural behaviour. Traditional monitoring methods often require physical presence, which can stress animals and potentially alter their behaviour. In contrast, thermal cameras can be set up at a distance, reducing the likelihood of human interference and ensuring more accurate data collection.
Versatility
A single thermal imaging device can be used to monitor a wide range of species, from small mammals and birds to large predators. It can even pick up flying insects, such as moths. This versatility makes it a cost-effective and efficient tool for ecologists. Instead of investing in multiple types of equipment for different species, researchers can rely on thermal imaging to cover several survey types. This multi-species monitoring capability is particularly advantageous in biodiversity studies and large-scale ecological surveys.
Seeing Through
Many animals have evolved camouflage to blend into their surroundings, making them difficult to detect with the naked eye or traditional cameras. Thermal imaging cuts through this natural disguise by detecting the heat emitted by animals, regardless of their camouflage. Additionally, thermal cameras can see through light foliage, providing clear images of animals hidden in vegetation. This ability to "see through" obstacles significantly enhances the detection of elusive species.
Minimal Additional Equipment
Thermal imaging technology is often a standalone solution, requiring minimal additional equipment. Unlike other methods that may necessitate supplementary lighting, traps, or tracking devices, thermal cameras can operate independently. This simplicity not only reduces setup time and costs but also minimises the logistical challenges associated with field research. For ecologists working in remote or rugged areas, the ease of deploying thermal imaging equipment is a substantial benefit.
Which specifications should you consider?
Whether you're a novice or experienced as a photographer, the number of different specs for thermal imaging can be quite overwhelming. Here are the most important features that you should look out for when purchasing a thermal camera for ecological surveys:
Thermal Sensor Resolution
The resolution of a thermal camera is measured in pixels, similar to digital photography. It defines the detail and clarity of the thermal images. Resolutions like 256 x 192 px are suitable for detecting larger animals or spotting heat sources over broader areas. This resolution provides basic thermal imagery that can help identify the presence and general location of wildlife. Higher resolutions like with the Pulsar Merger's 1024 x 768 px provide excellent detail and clarity which are helpful in identifying specific species and monitoring fine-scale temperature changes in the environment.
Focal Length and Field of View
Thermal camera lenses range from 6mm to 50mm, with each offering distinct advantages based on the requirements of the survey. Lens sizes of 15, 25 or 35mm are the most suitable for surveying applications, while 35mm upwards are more suitable for long-distance spotting. The field of view is generally inversely proportional to the focal length of the lens: shorter focal lengths provide a wider FoV, while longer focal lengths offer a narrower but more distant view. Pixfra's Arc A613 range stands out as being the widest FoV currently on the market at 32 degrees.
NetD
One key factor influencing the clarity of thermal images is the Noise Equivalent Temperature Difference (NetD). NetD is a measure of a thermal camera's sensitivity to temperature differences. It represents the smallest temperature difference the camera can detect as distinct from noise. NetD is typically measured in millikelvins (mK). Lower NetD values indicate higher sensitivity, leading to more precise and richly contrasted thermal images. Many thermal imagers, like the HIKMICRO Falcon range are now offering NetD values of less than 20mK.
Laser Range Finders
A Laser Range Finder (LRF) is a device that uses a laser beam to measure the distance between the thermal camera and a specific target. This feature is useful in ecological surveys where knowing the exact distance to an animal can provide valuable context for the data, or to help with daytime wildlife photography. While LRF enhance the capabilities of thermal cameras, its important to note that frequent use can reduce the battery life.
Connectivity
Thermal cameras equipped with hotspot capabilities can create a wireless network, allowing them to connect to smartphones or tablets and view the image in real time. Once connected, users can control the camera, store files, and access the album directly from their mobile device. This is a great option if you want to mount the camera to a tripod and leave it recording, or if you want to share your view with friends or colleagues.
Alternatively, you can use a plug-in device like the HIKMICRO Explorer E20 to connect directly to your phone.
Multi-spectrum
Multi-spectrum imaging systems use a combination of lenses to capture different types of images within one piece of equipment, making them very versatile for ecologist that cover multiple disciplines. Most frequently, a standard digital lens can be used in place of traditional binoculars. Paired with a thermal lens, this can offer high clarity images in various weathers or lighting conditions. Take a look at HIKMICRO's Habrok 4K Binoculars for a cost-effective option, optimised for daytime use.
Who do we work with?
Pulsar
Renowned for its high-quality products and global industry leadership, Pulsar offers a wide range of thermal devices and are a standout choice for a wide range of users. This Lithuanian brand prides itself on producing all its thermal imaging products in Europe, ensuring high standards of quality and precision. With a support and repair network based in the UK, Pulsar continues to set the standard for excellence in thermal imaging, providing reliable and innovative solutions for various applications around the globe.
HIKMICRO
Chinese-based thermal imaging manufacturer HIKMICRO stands out by offering high-quality thermal imagers at competitive prices and their commitment to innovation. The use of advanced technology combined with cost-effective pricing ensures that users can access thermal imaging without breaking the bank. With UK-based support and repair services, the company reinforces its commitment to customer satisfaction, making it a strong contender in the thermal imaging industry.
Whether you are a seasoned ecologist or new to the field, integrating thermal imaging into your research can provide valuable insights and improve the accuracy of wildlife monitoring. As the technology continues to evolve, it promises to enhance our understanding and conservation efforts, making it an indispensable tool in the world of ecology. We hope this blog has been helpful in guiding you through applications of thermal imaging.
If you're interested in thermal imagers for yourself or your company, browse our range to see what is currently available or feel free to contact us on 01451 833181 or [email protected] should you have any questions.
