Rescue from mowers
Every year in Germany, several hundred thousand wild animals are hit, mutilated or killed when meadows are first mowed in springtime: fawns, baby hares, pheasants, partridges or other ground nesters. For a long time, all attempts failed to spare animals this fate. But since 1999 equipment developed by the German Aerospace Center (DLR) in Oberpfaffenhofen has being successfully employed in ever increasing numbers by farmers and hunters. It uses infrared sensors to detect wild animals during springtime mowing, keep them from bodily harm, and assure their survival (Fig. 1). This so-called Infrared Wildlife Finder is marketed by isa industrieelektronik GmbH in Weiden.
Progress from continuing research
The portable Infrared Wildlife Finder (Fig. 2) is especially handy for locating fawns, but it is only partially suited for use with a tractor. This is because mowing usually takes place during warm and sunny weather, when the meadow itself has already become quite warm in places. Since the Infrared Wildlife Finder reacts to temperature differences, these warm locations in the grass are also detected, leading to false alarms. Frequent, short-notice false alarms are, however, not acceptable for a farmer busy at work. For this reason, a research project started in April 2008 funded by the German Federal Ministry of Education and Research. Besides DLR, the project team includes the companies CLAAS and isa industrieelektronik as industrial partners, plus TU Munich, Hohenheim University, and the Bavarian hunters’ association Jagdverband Bayern as associated partners. The project goal is to develop an infrared wildlife finder which can be mounted on a mower and reliably detect only wild animals. One of the options being investigated involves mounting various types of sensors on a mower boom (Fig. 3). This constellation would be used to check the next strip in line for mowing. Then, if an alarm sounds, there would be enough time to safely remove the animal before that strip is mowed. In addition to the well-tested infrared detectors, a radar system and different kinds of intelligent camera systems (reacting to the visible spectrum and to the thermal infrared range) are being studied, among other possibilities. Combining several sensor technologies significantly increases the chances of detection.
Air Rescue also for Fawns: A Flying “Wildlife Finder”
The rapid technological progress of recent years in the area of small, unmanned aerial vehicles has also made these aircraft attractive as a platform for wildlife rescue systems. IMF is testing a so-called octocopter, a rotary wing aircraft with eight rotors which can carry a payload weighing up to 0.5 kg on remotely controlled flights lasting about 16 minutes (see photo). During this time the wildlife finder can search an area of about 4 ha from an altitude of 50 m. It is equipped with infrared and video cameras whose images are transmitted to a ground station in real time. Initial trials with the octocopter have confirmed the basic feasibility of the system: during testing in various regions of Bavaria and Austria it detected 16 fawns.
The next steps should reveal whether this concept and the prototype can be turned into a marketable system.
The problems associated with rescuing wildlife during springtime mowing and a survey of the approaches tested to date are presented in the video “Wildretter - Für Tierschutz und Landwirtschaft” (in German only, see link at right)
Awards and Prizes
The work being carried out by the Remote Sensing Technology Institute and its partners in the area of wildlife rescue has received several awards: