Feral felines the ultimate killing machines

Peter d’Plesse

Cats evolved for the specific task of killing live prey. While having a soft spot for the domestic feline, I also shoot every feral cat I see, even if it means spoiling the hunt for game I’m really after. To hunt cats successfully, the more we know about them, the better.

Cats are hypercarnivores, demanding more protein than other mammals. Dogs survive on four per cent protein, Cats need 12 per cent by weight of protein (and kittens 18 per cent), explaining the deep instinctive urge to hunt. They have caused the extinction of native species and contributed to the decline of ground-dwelling birds and mammals. On islands, control is feasible. Elsewhere, management is difficult due to the lack of effective and humane broad-scale control techniques and the presence of domestic cats.

Cats have been in Australia since European settlement but probably arrived with Dutch shipwrecks in the 17th century. By the 1850s, cat colonies became established in the wild and intentional releases were made in the late 1800s in the hope of controlling rabbits, rats and mice. Cats are found in most habitats on mainland Australia, Tasmania and many offshore islands, although not in the wettest rainforests.

For management purposes, cats are divided into three categories: domestic, stray and feral – although individual cats may move between categories. Feral cats survive without human assistance and are the main target of control programs. The bad reputation of the dingo and subsequent trapping, shooting and poisoning may have contributed to this. Middle-sized predators such as foxes and cats may benefit from what ecologists call the ‘mesopredator release’ factor. Namely, ‘when the cat’s away, the mice will play’. Reducing dingo numbers may have enabled foxes and cats to replace them as predators. There is evidence to show that where dingo numbers are high, foxes and cats are scarce. The decline in small marsupials is closely correlated to the density of dingoes. The more dingoes, the more small marsupials. Where dingo numbers are low, foxes and cats can cut swathes through the population of native marsupials.

However, wider issues may come into play. Harvesting feral goats has become economically significant for many property owners in the semi-arid areas. Dingoes and feral dogs can drive goats away with direct economic impact on properties affected. Environmental management is not as simple as it first appears. Eliminating one unwanted species without careful planning can result in unanticipated outcomes. For example, eliminating cats on one island led to an explosion of rats that decimated birdlife worse than cats did.

Cats are solitary and predominantly nocturnal, spending most of the day in shelters such as a burrow, blackberry bush, log or rock pile. Rabbits aided their spread by providing food and burrows for shelter. Males usually occupy a home range of 10sqkm, increasing if food supplies are scarce. They are carnivores and survive with limited access to water as they use moisture from prey. They generally eat small mammals, but also birds, reptiles, amphibians, fish and insects, taking prey up to the size of a brush-tail possum.

From the age of one year, they breed in any season, with up to two litters of about four kittens. Few of the young survive. Dingoes, feral dogs and foxes restrict feral cat numbers by both predation and competition. Feral cats also fall prey to wedge-tailed eagles. They carry infectious diseases such as toxoplasmosis and sarcosporidiosis, which can be transmitted to native animals, domestic livestock and humans.

Cats have short, powerful forelimbs with long claws that are easily rotatable. Their bodies are lithe with a flexible spine and muscled hind limbs. This delivers power, agility and quickness of movement. They move with fluid motion because they walk on their toes. Their skull shape produces a foreshortened face with a solid anchor for powerful jaw muscles to increase the bite force of the canine teeth. Apart from the lynx and the short-tailed bobcat, the tail can be one-third to one half of the head and body length, acting as a balance when moving through trees, steep terrain or making sharp turns in pursuit of prey.

Because the face is foreshortened, cats have fewer teeth than other mammals, usually 28 to 30 compared with 42 for dogs. There are small incisors for holding and nibbling. Rear molars move against each other like scissors for cutting and slicing. Ethologist Paul Leyhausen suggests that the canine teeth fit between the neck vertebrae of a prey victim like ‘a key’. He also suggests that nerves at the base of the canine teeth allow cats to feel for the gap between the prey’s vertebrae before biting down. This forces vertebrae apart to snap the spinal cord. They are a perfect killing machine, evolving in the same mould as the shark and crocodile. Of all the carnivorous animals, only cats use their front paws to hold prey ready to deliver the fatal bite. All cats are terrestrial but have retained the ability to climb using sharp, retractable claws to aid survival.

The cat family has a huge range of body size. The feral cat is fairly small in size but still deadly for native wildlife. However, given examples shot in the wild, size range is an interesting question that merits a separate article.

Cats are excellent survivors, assisted by superb camouflage. Most felids are blotched, stripped or spotted, although black in feral cats is fairly common. As feral pigs demonstrate, this is an effective camouflage color in Australia where bright sunlight can produce deep shadows. Grey or ginger striping also works well.

Cats have superb senses to enhance their ability to hunt. Eyes have evolved to hunt by day and night and are large in proportion to their body, only slightly smaller than humans’. Their pupils contract to a vertical slit in bright sunlight but expand to take up almost the whole eye in poor light. Caught in a spotlight, their eyes shine with a distinctive yellow glow. This distinctive eye-shine comes from the mirror-like tapetum reflecting back through the retina to give the sensory cells a second chance to respond. The sensitivity of cat eyes to light is six times that of a human. Their binocular vision is well developed, allowing them to accurately judge distance when pouncing on prey. Their peripheral vision is excellent too, resulting in that ‘staring into space’ attitude that creates an impression of aloofness. They are not being aloof; they see perfectly well off to the sides and don’t need to turn their head!

Their whiskers aren’t there for decoration, providing ‘sight by touch’ and are useful in hunting, especially at night. They detect slight changes in air currents and allow obstacles to be avoided during a stalk. Hearing is another sense perfectly tuned to hunting. While humans hear in the 15 to 20kHz range, cats can hear in the ultrasonic 65 to 70kHz range. They can’t produce sounds in this frequency range, so their ability to hear them is probably intended to enhance hunting. Their ears are shaped to amplify sounds and locate direction and they are about 30 times more sensitive to sound than human ears.

A cat’s reliance on smell is less well understood but the complex structure of their olfactory system indicates they are highly sensitive to scent. Cat scent probably contains much information about identify, sex, status, reproductive status and the time a urine mark was made. Certain spots in their territory are scent marked repeatedly like ‘traffic lights’ to indicate whether an area is being used and by whom. Whether a cat proceeds or changes course depends on the sex, status or relationships of the cats involved. Signals generated by scent marking and their impact on wild cat behaviour are invisible to us but it helps to be aware that such a powerful mechanism is at work.

Apart from the standard ‘meow’, cats have at least 12 sounds used to communicate. Purring is most usual between mother and kittens but there is also the spit, hiss and growl (with variations) common to all cats.

While availability of water and cover are important, food supply dictates the distribution of cats. Females rear young alone so access to food is important. Distribution is governed by the size and availability of prey in time and space. Where prey is abundant, females raise their young in a small exclusive territory. Otherwise, territories are large and may overlap.

The distribution of females influences the distribution of males. Where females are common, dominant males may monopolise several females. Where female ranges overlap because of scarce resources, male ranges also overlap, reducing the opportunity to maintain exclusive mating rights. Males may be forced to roam over a large area and compete for access to females.

The home range of any animal does not have fixed boundaries, varying according to resources, population and seasons. Acquiring a home range is important for breeding and individuals without an established home range have limited opportunities to mate. They tend to live in marginal habitats and travel extensively looking for breeding opportunities. They may pass through an area checking scent marks or challenge the current occupant.

Even though most wild cats are solitary, they are influenced by a social system maintained through scent marks, vocalisations and the odd face-to-face encounter. It is likely that cats with overlapping home ranges know where they are in relation to each other most of the time. The only cats that live in groups are lions, cheetah males and domestic or feral cats. The reason is uncertain but most likely involves food. Feral cats have been observed living in groups in farmyards, offal dumps and garbage tips. These artificial food sources may provide a plentiful food source to support highly structured social groups. Open habitat supporting a large amount of game with stiff competition from other scavengers may create the conditions for the formation of groups by the big cats.

The density of feral cats is an interesting question and figures of 18 feral cats per square kilometre have been quoted but I suspect the real density of feral cats varies greatly across Australia, which hunters can help manage humanely.

Hunting feral cats is challenging. They are often an opportunistic target, popping up when the hunter is after other game. Spotlighting is an effective strategy for those so inclined. Night hunting will catch cats at a time that matches their finely-evolved hunting ability. More will be seen as they feel safest in darkness.

Day hunting requires planning and patience. Luring them in with suitable bait can work. I have bagged some using the all-pervading scent of fish heads suspended just above ground level to create a teasing lure. The fox whistle and predator-type callers are useful. They certainly attract the attention of domestic cats. Glassing rabbit warrens can also be productive. Day hunters need patience and will probably set up a number of lures to be checked with binoculars and careful movement. Dusk and dawn are obvious times but I have come across them during the day moving through channels or other suitable habitat. Trapping can be effective but may not be a strategy truly reflecting the values of pure hunting. Perhaps there are times when values have to be weighed against environmental benefit.

Calibres like the .222, .223 and .22-250 are perfect for taking feral cats. Given the random chance of coming across the animals, the firearm you are carrying is the one that will bag the game. Any firearm will do the job if used within its limitations as the hunter is providing an environmental service. The .22 rimfire needs judgment and discipline but can do the job. A combination gun is useful. Mine is a Brno 7×57 and 12-gauge. The shotgun barrel can carry a solid slug, SG or any other load to cover likely game.

If the chance arises to hunt a feral cat, take it! The species is an underrated trophy. They should be respected for their abilities and deserve quick despatch from a bullet.

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