Notes on the forensic evidence of strangulation on a lynx.
Forensic evidence of strangulation of a lynx is externally very difficult, in most cases not possible. The winter fur of the lynx in particular consists of fine, dense and very elastic hair. The diameter of the hair depends on the subspecies and ranges from:
Primary hair: 0.051 - 0.071mm
Secondary hair: 0.030 - 0.042mm
The hairdensity of the winter coat:> 6000 max. 9000 hairs / cm².
Lynx do not have tubular hair, which is highly fragile.
In Canada and the USA, lynxes can be caught, killed and the pelts marketed commercially. North American subspecies pelts are legally exported worldwide, particularly to the EU.
The trapping method is essentially limited to the use of leghold traps. The killing by strangulation of the still living, captured lynx by the trapper only takes a few seconds and, apart from the damage to the paws from the leghold traps, leaves hardly any visible external injuries.
Alternatively, the "Lynx Snare" offered on the North American market is used. This is made of highly flexible twisted steel wire, with a ratched which blocks a return movement, so that the lynx trapped in it inevitably strangles itself through its liberation efforts. The entire killing process of strangulation only takes a few seconds and leaves hardly any visible external injuries on the neck (Fig. 1).
The trapping method and the associated killing by strangulation is described as being particularly “gentle on the fur”. From the mentioned catching nations, lynx skins are almost exclusively exported without paws (Fig. 2 and 3)In order to exclude the visible evidence of the leghold trap, the paws of the fur are often removed. But one also saves the time that it takes skinning the paws, which are worthless for the fur-processing craft. In terms of animal welfare law, one is always on the safe side, since killing by strangulation cannot be proven - or recognized.
Evidence of killing by strangulation is not possible on raw hides, which partially have only been dried, when they are imported into the EU. The specimens appear externally undamaged and
uninjured. The North American catching technique is another killing method that is difficult to detect for wildlife forensics and is readily available on the Internet.
Lynx are among the particularly protected wild animal species in the EU. Persecution or killing is a criminal offense. Any loss of an individual from a rebuilding population can create a problem for the survival of the species. The protection of each specimen is therefore essential!
The use of huntable game by the predator lynx, which is also sought after by those who are entitled to hunt, results in conflict scenarios only in Germany, which often end fatally for the lynx.
Poaching takes place in German forests, and this is not only known in hunting circles.
Poachers are not hunters. Poachers can, however, meet the requirements for hunting by passing the hunter's examination, the legal acquisition of hunting weapons and a hunting opportunity.
Poaching of protected species has increased considerably, and lynxes have suffered particularly in certain German federal states.
Killing wild animals with snares has always been the practice of poaching.
Note: A much discussed case from the state of Bavaria has been brought back into focus - strategically wanted - .
Since the case is of public interest, excerpts from the review will be made available.
Calculating the snare force
The European lynx are larger and more powerfully built than the two North American species. The question now arises whether the killing technique that is used in North America for the described lynx hunt can in principle also be used for the stronger European lynx with the same success. For this it was necessary to calculate the forces that are necessary for the killing by strangulation of a European lynx. Depending on the age and the neck circumference of the specimens, the effort that is transferred to the neck of the lynx by the snare force was calculated.
A loop is pulled with the tensile force W , see illustration. This force is distributed to both sides of the loop as F, depending on the angle a.
If the loop is opened, the angle a is small. This increases when the loop is tightened. Theoretically, the angle is therefore between 0 ° -90 °. However, it is assumed that the loop cannot form a complete circle, therefore a maximum angle of a = 80 ° is assumed.
Case 1: Neck diameter 102mm
Neck diameter 102mm (circumference 320mm)
This corresponds to an approximately 2 year old strong specimen of a European lynx in winter fur
Case 2: Neck diameter 58mm
Neck diameter 58mm (circumference 180mm)
This corresponds to an approximately 7.5 month old specimen of a European lynx in winter fur
All of the specified tensile forces can be applied by an adult without any problems. The loop is in the form of a wire, the pressure is distributed automatically and is applied equally everywhere .
This results in an external compression of the soft tissues of the neck, especially the vessels, first of all veins and arteries. This is followed by respiratory impairment due to pressure on the airways (trachea).
The reduction of the arterial blood supply to the brain by squeezing aa.carotides and aa.vertebrales.
What these have in common is the typical presence of cord marks on the neck muscles with conspicuous soft tissue or congestive bleeding. Strangulation can lead to bleeding in the subcutaneous tissue, in the soft tissues of the neck and in the muscles, as well as in injuries to the neck organs. These findings are not only evidence of a pressure effect on the neck, but also of forensic importance for the subsequent assessment.
The frequently documented bleeding in the eyes is also important for the various forensic questions. The possible causes of the bleeding in the eyelid and conjunctiva have been adequately described in the literature due to violence in the neck area / strangulation. The use of congestive bleeding ultimately also requires the assessment of the entire constellation of findings.
Less experienced pathologists can “overlook” the subcutaneous hemorrhage in the neck , which is why the diagnosis of strangulation cannot be made in the first place. In such a case, the term malpractice can be used.
Team Zootomie 14.06.2021