Bats constitute a zoological group also known as “chiroptera”, which means hand transformed into wing. They have evolved for centuries in different shapes and sizes,counting at present with more than 900 species. Of these, at least 25 inhabit the Iberian Peninsula. And the conservation of Spanish bats is tremendously important.
Characteristics and conservation of Spanish bats
Bats are animals that contribute to pollination. For this reason – and others – these mammals are so important.
The most outstanding feature of bats is their ability to fly, which distinguishes them from other mammals.In order to do so, they develop an interdigital membranous structure. This membrane is supported by the evolutionary development of bats that has led them to lengthen the bones of their fingers.
It is known that bats do not build their own nests.What they do is resort to shelters to protect themselves from adverse conditions, their natural enemies and the inconvenience. These shelters, depending on their function, will be:
- Hibernals, to spend this period during the coldest times of the year. They must have special characteristics, such as that the temperature does not fall below 0ºC, that the humidity is high and that there are no drafts.
- Day or intermediate shelters, after hibernation, during migrations.
- Childbirth Shelters.
Depending on where the bats are, we talk about:
All European bats feed on insects, usually at night. Hunting territories vary depending on the species, preferences for the prey and the abundance of it.
Bats follow a fixed flight path in a circle, again and again, until they catch all the insects in an area. Then they change trajectory. And they locate the prey by ultrasound.
It is estimated that they consume between 500 and 1000 insects a day, which highlights their importance as biological controllers of arthropod populations.
Bats are guided by ultrasound, as are whales and dolphins. They emit very short waves, which are the most useful for producing echoes in confined spaces. This allows them to dodge obstacles and feed very effectively. What does not explain is how they are able to orient themselves in long-distance trips.
Like many other mammals, bats have two very different periods throughout the year. As the nights get longer, the cold arrives and the food is scarce, they look for peaceful shelters to begin to hibernate. During this period the heart rate and breathing decrease, feeding on the fat stores stored during the hot months.
After the hibernation period, bats begin their movements to summer shelters. This is how migratory species differ from sedentary ones.
The reproduction of European bats varies by species. Mating occurs in the winter shelter, but fertilization of the ovum does not occur until spring, storing, until then, sperm in the female’s genitals.
The gestation period lasts between 45 and 70 days and, at the time of delivery, the females are grouped in the shelter for this purpose. Most stop a baby. However, this low birth rate is compensated by its longevity.
The conservation of Spanish bats: why do they disappear?
Despite the shortage of natural enemies,the populations of this flying mammal decrease year after year. This is due to:
- Acid rain.
- The forest fires.
- The destruction of natural habitats, shelters, etc.
- The use of insecticides and pesticides that leave them without food, or worse, intoxicate them.
- The presence of ectoparasites in their fur, such as fleas, bedbugs or ticks.
The conservation of Spanish bats: how can we protect them?
In Spain all bat species are categorized as “of special interest” on the IUCN List. This makes them deserving of special attention based on their scientific, ecological or cultural value. In addition, this legal protection is reinforced by the inclusion of all species in international and European conventions.
Apart from these legal provisions, other protective actions stand out. First, the protection of shelters, placing bars in the caves that prevent the entry of people. Second, creating new shelters. And thirdly, disseminating and promoting its conservation.