Habitat loss or destruction is a direct consequence of our current economic and social system, as well as one of the greatest threats to animal species and to wildlife sustainability. Biodiversity reduction and the extinction of species are some of the devastating effects of this degradation, which is at times irreversible.
However, there are also consequences at a local level, which especially affect nature lovers: habitat loss makes wildlife watching in natural environments increasingly hard. In other words, it has become a lot less likely to be able to watch wild animals in their natural habitat.
Wildlife viewing is not easy; apart from habitat loss, there are other factors that make it difficult to watch animals in the wild: most of them are active primarily at night or during twilight, and a lot of them have highly developed senses (such as hearing, smell or sight), which allows them to avoid contact with anything related to mankind.
In order to effectively track and watch animals, and better understand their behaviour and relationship with their environment, it is important to pay attention to any proxy indicators that may reveal the presence of different species: footprints, signs, traces, etc. After spotting one of these indicators, it is easier to interpret the different signs that might appear. These indicators can provide a lot of information about the way of life of the different species, and are key in understanding the characteristics of each individual, such as its age, size or diet. The only way to discover these details without directly seeing the individual is through efficient tracking.
Most of these signs are temporary, so they disappear after a few days (or even hours). Nonetheless, there are instances of footprints and signs that have lasted thousands of years, such as the fossil footprints of cave bears found in the south of France, which date back to 15,000 to 20,000 years ago.
In essence, the analysis and study of the following types of indicators make it possible to obtain information about the characteristics of the animals that left them:
Types of footprints and foot structures
Footprints are the easiest types of signs to recognise, especially in snow or in soft and sandy soil. However, it is important to have previously studied the structure and appearance of the paws (or hoofs) of the different species for correct identification.
There are plantigrade and digitigrade species. Plantigrade locomotion means walking with the sole of the feet and hands is in contact with the ground; hares are plantigrade animals. Digitigrade animals stand or walk on their digits or toes; lynxes are digitigrade. If the animal’s claws are non-retractable, such as those of wolves or foxes, they will appear in their footprints. If their claws are retractable, such as those of wild cats, they probably won’t leave such trace. There are also species with hooves, which leave a very characteristic footprint.
Droppings: a clue on eating habits, diet and behaviour
Though it might seem a little off-putting at first, the study of animal droppings can reveal a large amount of important information, such as the eating habits and diets of different species. In fact, thanks to the non-digestible parts of the foods, it is sometimes possible to know exactly what the animal has eaten; this is the case when the droppings have traces of feathers, fur, shells or chitin fragments (present in the exoskeleton of arthropods). For example, it is common to find remains of crustaceans in otter droppings. These studies allow not only to learn about the animal’s eating habits, but also to identify the species itself.
Apart from all this, the smell of an animal’s droppings is also a valuable source of information. Mammals have scent glands (located in the genital area) that secrete a series of substances that give the droppings of each species a characteristic and unique smell. This secretion is key during mating times, as it lets potential mates know that an individual is willing to mate, favouring sexual selection.
Animals also use the smell of their droppings to mark their territory; to do so, they also place their excrements in specific locations or positions. Some animals, such as foxes, try to defecate in elevated locations (rocks or fallen trunks), for the smell to disperse more easily. Others, such as badgers, by contrast, prefer to do so in latrines or holes in the ground.
Signs and marks on food
A lot of animals leave marks or some type of evidence that generally manifest in the shape of signs (made with teeth or other body parts) on the food they consume, may that be tree or bush branches (debarking, common in deer), fruits (gnaw marks, left by rodents) or even in the carcasses of their preys (carnivores usually leave biting marks). As with droppings, analysing animal troughs and food will provide valuable information about the diets of the different species, as well as about their eating habits.
Burrows, dens and shelters
Usually, and especially during breeding seasons, animals take refuge in different types of dens and burrows, which are hidden and hard to access (bird nests are a classic example). These shelters may be permanent, but they are generally temporary. The location, size and characteristics of burrows are key in order to identify their “occupants”.
For example, animals like foxes, rabbits or badgers build their burrows in the ground, creating a series of interconnected galleries and tunnels. On the other hand, deer and bucks don’t build a refuge in itself; they prepare resting areas in forests, where they flatten the vegetation to lie down.
Mud holes and mud baths
Mud holes are swampy and muddy areas where certain species take mud baths to keep their skin healthy, regulate their body temperature and protect themselves from insect bites. In the surroundings, it is common to find trees with traces of mud, a sign that animals have been rubbing against them to dry off. These traces are easy to identify and are left by species such as boars, for example.
Scratches and marks on trees
In spring, it is common for some types of deer, such as roe deer, to rub their antlers against tree trunks in order to remove its velvet (a layer of fuzzy skin that protects the antlers that grew out throughout the winter), leaving very obvious marks in the process. Bears also nibble and scratch branches and trunks, especially during mating times.
Pellets: an everyday element for some birds
In the areas surrounding bird nests and roosts, it is common to find compact pellets, made of hair, feathers, vegetation… Pellets are made of those components that birds cannot digest, so they react by regurgitating these materials. This is common in nocturnal rapacious birds, corvids or gulls, and one can deduce what species expelled a specific pellet by analysing its content, shape and size.
Translated by Carlos Heras