Effects Of Tourism And Human Presence On Mid-Sized Animal Populations

Tourism and the environment have a close relationship of dependence. Every tourist activity needs an environment, and whether this environment is natural or not, it undergoes a process of de-characterization in its natural setting by human action. Nature is essential for the development of tourist activity, and without a doubt arouses fascination in people, who seek to connect with it, recover their energies and relieve the tensions of everyday life.

Tourism has been causing harmful impacts to the environment, especially with regard to coastal areas increasingly sought by tourists. In these coastal areas, people end up triggering a race for real estate expansion, highlighting the presence of large tourist enterprises on the coast. Their use and occupation in these areas take place in a disorderly manner, bringing irreversible damage to the environment.

The vulnerability of wildlife to disturbances is complex, however, several studies suggest that animals subjected to non-threatening, predictable and frequent disturbances may become accustomed. However, in the last decades, several investigations have demonstrated that the traffic of visitors and other tourist activities can lead to the loss of biological diversity. This loss consequently interferes with the ecological conditions essential to the correct functioning of the ecosystem productivity. This is seen by the extinction of endemic species and the loss of rare or endangered animals. The Atlantic Forest, which is one of the biomes that holds the largest number of endemic birds and endangered species on the planet, has suffered a reduction of about 150,000km² / year, leaving only 7% of its original cover.

Of tropical forest inhabitants, mid-sized mammals are among the most vulnerable to ecological disturbances. Their populations are threatened by many different anthropogenic pressures such as loss of habitat, competition for resources with humans, as well as poaching and trafficking. Losses of mid-sized mammals are often particularly acute in small remnants of forest, as well as, on islands throughout the world’s tropical regions. Insular environments are potentially more susceptible to ecological threats and pressures than their mainland counterparts due to their isolation.

Here, we study the distribution of mid-sized mammals on an island in southeastern Brazil (Ilha Grande), covered by Atlantic forest. Mid-sized and large mammals are disappearing rapidly in mainland areas of the Atlantic forest due to severe habitat modification and other anthropogenic pressures. Although reserves exist, their effectiveness is largely unknown. Ilha Grande supports a State Park and a Biological Reserve which together cover 80% of the island. Despite the amount of protected area, mid-sized mammals could likely be influenced by the presence of human settlements and rapid growth of eco-tourism. Using camera-trapping, we evaluated the importance of habitat characteristics and anthropogenic factors on the presence of mammals.

The main question we address in the published work is whether human presence and activities influence the way mammals move and forage on the island. The majority of the island area is under protection, however, one side of the island is noticeably more populated by humans and thus, disturbed. We found strong evidence that human presence changes the way mid-sized mammals forage and move, which is reflected on the probability of detecting them, as a consequence of local abundance heterogeneity. Evidence shows that human presence explains the local abundance heterogeneity better than habitat characteristics. We used up-to-date methodology based on maximum likelihood inference to illustrate this important issue on protected area efficiency inside a biodiversity hotspot biome, and we believe our results are novel and important to be shared with a broad spectrum of the scientific community.

These findings are described in the article entitled You can’t run but you can hide: the negative influence of human presence on mid-sized mammals on an Atlantic island, published in the Journal of Coastal Conservation. This work was led by Atilla Ferreguetti from Rio de Janeiro State University.