Giraffes that live in the surrounding Maasai villages, form weaker social bonds and communicate with a smaller number of relatives. This was pointed out to a six-year study in Northern Tanzania, the results of which are published in the journal Journal of Animal Ecology. The authors believe that the presence of a person giraffes behave more cautiously.what prevents them to interact with each other.
Speaking about the impact of humans on the life of wild animals, usually referring to the hunt or the transformation of natural ecosystems. However, the consequences of human activity can be much less obvious. For example, there is growing evidence that the neighborhood is reflected in the social structure of a number of types. Unfortunately, this important topic remains poorly understood.
A team of zoologists led by Monica bond (Monica L. Bond) from the University of Zurich decided to find out how human presence affects intraspecific relationships Masai giraffes (Giraffa camelopardalis tippelskirchi), living in Tanzania and southern Kenya. The focus of the researchers was the population from the region of Tarangire in Northern Tanzania. Here are two national parks, private ranches and agricultural lands pastoralists-the Maasai. Fences and fences between them, so that wild animals can easily move from protected areas to unprotected.
For six years, scientists collected data about the interactions of 1139 adult females giraffes. Such individuals most often involved in social relationships with relatives – for example, they may choose partners for cooperative feeding. As the pattern of spots on the skin of each giraffe is unique, professionals were easy to identify individual animals.
Analysis of the obtained material confirmed that for females giraffes in the Tarangire region typical complex network of social relations. The local population is divided into groups of 60-90 individuals whose members periodically interact with each other, but avoid contact with representatives of other groups. Such selectivity is maintained, even when multiple teams occupy the same territory. While individuals living close to the traditional Maasai villages-with Bohm, rarely communicate with each other and have a more limited circle of acquaintances.
Masai giraffes belong to the tolerant: they do not hunt them and is not seen as competitors to livestock. However, the region has a lot of alien poachers, which the giraffes run away from any humans traveling on foot (for jeeps with tourists beasts do not pay attention). This behavior prevents to form and maintain social ties. The negative role played and the felling of trees, whose leaves feed the giraffes.
It may seem strange that people actually come to the villages. According to the authors, they are attracted by the absence of lions and hyenas, which consume the cattle of the Masai. This is especially important for females with cubs. Thus, giraffes have to make a choice between security and communication with relatives.
It is difficult to say how the violation of social relations harm the welfare of the giraffes. However, the researchers suggest that it, along with poaching and habitat loss, can partly be explained by the serious reduction in the population of these herbivores in recent decades. The Masai subspecies, which was dedicated to the study, was especially hard hit: its population has declined by 50 percent.
Sometimes life near the person having a deeper impact on the lives of wild animals. For example, recently, scientists have establishedthat the foxes living in London, changed the shape of the skull. The muzzle of urban animals become wider and shorter, and the volume of the brain decreased. Similar changes are characteristic for domesticated animals.
Sergey Knee High