Brief justification
In order to develop effective measures for the protection and conservation of wildlife in the Arctic and Antarctica, regular monitoring of the condition and number of animals and their habitat is necessary. At the top of the food pyramid are marine mammals – indicators of changes in the entire ecosystem of the polar regions. Aerial photography has long been used to estimate their numbers. Until now, little is known about the number of marine animals. Effective monitoring in the harsh conditions of the polar regions requires new methods and technical means of collecting materials and data, as well as modern methods of their processing.
Goal
Monitoring of the condition and multi-species aerial survey of animals in polar regions.
Brief description of the project
To account for marine mammals, aerial photography is carried out from several unmanned aerial vehicles (UAVs) based on an icebreaker. UAVs are equipped with cameras in various areas of the optical spectrum, including thermal imagers and ultraviolet cameras, as well as navigation systems, altimeters and other sensors. The icebreaker provides forward movement in the latitudinal direction, and the drones are shooting tacks mainly in the direction perpendicular to the movement of the icebreaker.
After preliminary onboard processing and compression, the collected materials are promptly transferred to the processing center on the icebreaker for further flight planning and further to the coastal center for thematic data processing and analysis. To estimate the number of animals, sample data is extrapolated and the number of animals is estimated.
Collection of materials and data processing
Determining the area of work and choosing the time of aerial photography
The initial stage includes the definition of the area of aerial survey work. To do this, it is necessary to take into account the size of the territory, the type of terrain and the density of distribution of animals. The choice of the optimal time for shooting depends on the life cycle of the animals. Aerial photography should be performed during such a period of animal activity when the most complete air accounting can be performed.
The choice of drones, routes and heights of aerial photography
The choice of UAV depends on the job specification. There are drones for detailed shooting of small areas and larger aircraft for covering large areas. Flight routes are laid out in such a way as to obtain the most complete and uniform coverage of the area without overlaps or large gaps. The altitude of the flight should provide both sufficient image resolution to detect animals, and provide a wide area circumference for a larger sample.
Methods of aerial photography of animals
Methods are used both for the direct detection of animals and for the traces of their vital activity. In addition to conventional digital photography, infrared, ultraviolet and other types of photography are used in the visible range of the spectrum. The use of thermal imagers makes it possible to identify animals by thermal trace even in conditions of low visibility or dense vegetation, and the use of ultraviolet light allows you to detect masked individuals.
During flight accounting, special requirements are imposed on the equipment: cameras must have high resolution, have a wide viewing angle and be stable when vibrating. The angles of the shooting equipment must be metrologically calibrated. In addition to aerial photography equipment, a navigation system, an accurate altimeter, and aircraft position sensors are required for accounting.
Decryption of air photos
At the stage of decoding aerial photographs, specialists analyze the obtained materials, classifying the types of landscape and identifying animals on the ground. Both manual methods and computer methods using neural networks are used to detect and recognize animals.
Counting animals and correcting under-counting
Counting the number of animals in the images is carried out by directly counting the individuals in the images. At the same time, the under-accounting at the edges of the accounting band is corrected using statistical models. The degree of underestimation is also assessed due to the complexity of the terrain and the peculiarities of animal behavior.
Extrapolation and interpretation of air accounting results
At the last stage, the data are extrapolated to the entire studied area and estimates of the number of animals are made. The results are interpreted by biologists together with other specialists. The results of the surveys will then be used to assess the state of polar ecosystems and develop strategies for biodiversity conservation.
Preparation for work
The implementation of the entire project requires thorough scientific and technical training in biological, environmental, geographical and other areas, as well as serious mathematical and organizational and technical support of the work. An integrated approach dictates combining the efforts of professionals of different profiles – from biologists to technical and IT specialists.
Among the priority areas are the following:
· “census” of animal species living in polar regions and characteristics of their habitat;
· development and improvement of methods and techniques of aerial photography and methods of collecting materials;
· improvement and automation of methods of processing materials and accounting of animals;
· improvement of extrapolation methods and algorithms for estimating the number of marine animals;
· improving the interpretation of the results of the aerial survey of animals in the polar regions.
By Nikolay Kuznetsov, n-kuz@yandex.ru January 2023
