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correctly however, protected species may unintentionally get caught. Further, snares and traps may intentionally be used to catch/kill endangered wildlife. 21 3.2.2.1.1 Snares Snares are simple devices to catch (small) mammals through anchored cables. They trap an animal around its neck, body or feet. Animals caught in snares alive are at risk of starvation and dehydration or hyper-/hypothermia if trapped for a longer period. They may struggle vigorously leading to progressively tightening of the wire and thereby cutting deep into the tissue with typical lesions that can easily be detected at necropsy. Sometimes, animals caught alive are killed by shooting, thus radiography should always be applied in such cases. Figure 1: A typical snare to catch certain species of wildlife (Source: Wikimedia Commons). 3.2.2.1.2 Traps Different types and sizes of traps exist, ranging from cage traps to catch animals alive to body-gripping traps (e.g. conibear traps; spring-traps) that are designed to quickly kill an animal. Figure 2: Some types of traps (from left to right): Cage trap for trapping animals alive, conibear trap and spring trap, both designed for fatal trapping (Source: Wikimedia Commons). 22 As with snares, animals caught in cage traps are at risk of starvation and dehydration or hyper-/hypothermia if trapped for a longer period and sometimes the trapped animals are killed by shooting. Body gripping traps kill the target animals (e.g. foxes, martens) quickly by tightly shutting jaws around the body, especially the neck, of an animal. However, non-target animals are at high risk by this type of traps, even if they are used legally. Especially if placed incorrectly (or intentionally), many species of birds of prey will get lured to the trap by the bait that is normally placed into the trap. When triggering the release mechanism, the jaws of the closing trap may instantaneously kill the bird or it will close around its feet (or sometimes other body parts) leading to injuries that range from rather superficial wounds to severe fractures and even amputation of the leg. The degree of the injuries is highly dependent on type and size of trap. 3.2.2.2 Shooting In contrast to illegal shooting of wildlife, most shooting incidents in humans (homicide, suicide) involve handguns and the majority of the human forensic literature focusses on handgun shooting characteristics. Therefore, the respective literature should not be simply extrapolated to shooting incidents in wildlife. The interpretation of shooting wounds by the veterinary pathologist requires some knowledge of firearms and the ammunition used in wildlife crimes. This chapter shall present the respective background knowledge in more detail. 3.2.2.2.1 Types of firearms and ammunition 3.2.2.2.1.1 Firearms There are several types of firearms that are used in wildlife crimes, mostly rifles and shotguns. To a lesser extent, handguns and air- or gas- powered guns may be used, although they produce significantly less energy and hence are deadly only in small animals and at short distances. Most firearms except shotguns have rifled barrels, meaning that spiral grooves have been cut into the bore of the barrel. The purpose of this is to force the bullet into a longitudinal spin for better stabilisation and accuracy during flight. Rifling typically leaves tool marks on a fired 23 bullet that may be characteristic for an individual weapon. The tool marks may be investigated in a special forensic laboratory and serve as important evidence and thus bullets recovered from a carcass should be handled with great care and kept as evidence (see chapter “Veterinary pathological Investigations”). 3.2.2.2.1.1.1 Handguns Handguns are small firearms designed to be held and fired single-handed (although using both hands will increase accuracy). They are considered low-velocity weapons since the cartridges of handguns are shorter and hence carry fewer amounts of propellants (gunpowder) producing less energy than rifle ammunition. The muzzle velocity (i.e. the speed at which a bullet leaves the barrel) of handguns typically ranges from 200 m/s to under 500m/s, depending on calibre, barrel-length, and amount and burn rate of the propellant. Due to the short length of the barrel of handguns and the relatively low velocity and thus energy of the bullets, handguns are much less precise and accurate than rifles. They are used only at short distances in hunting (e.g. finishing shots; self-defence purposes against attacking wild boars). For the same reasons, bullets fired from handguns are more likely to be retained in the carcass of an animal compared to bullets from rifles. The two main types of handguns are revolvers and pistols. Revolvers comprise a rotating magazine holding 5 to 10 cartridges. They are either single action or double action types. While in the former the hammer must be cocked manually each time a shot is to be fired (thus causing a rather slow shooting cadence), double-action revolvers fire a shoot each time the trigger is pulled. The cartridges are not ejected automatically after firing in revolvers. Pistols are mostly semi-automatic firearms, meaning that they automatically extract and eject the cartridge and load the next bullet into the chamber once being fired, thus ensuring a high shooting cadence (a bullet is fired each time the trigger is pulled without the need of manual reloading in between). In pistols, the cartridges are stored in a removable magazine (typically holding between 10 and 20 cartridges) in the handgrip of the weapon. 24 Fig. 3: The two types of handguns: Revolver (left) and Pistol (right) (Source: Wikimedia Commons). 3.2.2.2.1.1.2 Rifles Firearms that are designed to fire projectiles from the shoulder are called rifles. They have a rifled barrel and are high velocity weapons with muzzle velocities ranging from app. 600 m/s to more than 1000 m/s. Rifles are much more accurate (for hunting purposes up to 300m; more for military purposes) and more precise than handguns and thus are used for shooting at longer distances. The types of rifles comprise single shot rifles (no installed magazine, they have to be loaded manually after firing), bolt action rifles (loading is done by moving a handle back and forward, thereby extracting the used