Birds Found Exclusively in Atlantic Forest
No less than 41%, or 88 of the 214 species of birds exclusive to the Brazilian Atlantic Forest, could soon disappear, according to information published recently in the prestigious British magazine, “Nature”.
Scientists believe that four species are completely extinct (the mutum do nordeste, the saira-apunhalada, the tietê de coroa and the entufado-grande).
Biodiversity in the Atlantic Forest
When the Europeans started colonizing the lands that were later to become Brazil, they found two large forests, made up of true mosaics of different plants.
The largest of these, which remains preserved, stretched across the River Amazon basin, occupying the entire northern region of Brazil and significant parts of neighbouring countries. This complex and diverse combination of continuous plant formations was called the Amazon Forest. The other, the Atlantic Forest extended along the coast from Rio Grande do Norte to Rio Grande do Sul, covering hundreds of kilometres within the continent, in the South and South East regions, to reach Argentina and Paraguay.
The extent and broad coverage of the Atlantic Forest, occupying extremely varied latitudes, with widely differing climatic conditions, led to the formation of different environments that provide enormous biological diversity.
Within the profusion of fauna existing in the Atlantic Forest, some species are broadly distributed and can be fond in other regions, as in the case of the painted lynx, leopards, gatos do mato, tapirs, jungle hens, wild pigs, some parrots, owls, sparrow hawks and many others. What most impresses students is the enormous number of endemic species, those that cannot be found anywhere else on the planet. These number 51 species of mammal, including 21 species and sub-species of primate, and 160 species of bird. In relation to amphibians the number is even more staggering: of the 183 species catalogued, 91.8% are considered as being endemic.
Compared with the Amazon forest, the Atlantic Forest is proportionally more biologically diverse. In the case of mammals, for example, 215 species are catalogued in the Atlantic Forest, compared with 353 in Amazonia, despite the latter being five times bigger than the original area of the former.
The numbers relating to plants are equally amazing. Of the ten thousand species known, 50% are endemic. The level of endemism increases significantly when the species of flora are separated into groups, reaching 53.5% for tree species, 64% for palms and 74.4% for bromeliaceae.
A recent study carried out by Brazilian and American scientists revealed that the Atlantic Forest has the greatest tree diversity in the world. The team, comprising specialists from the New York Botanical Garden and the Cocoa Research Centre, found 450 tree species within the area of one hectare south of Bahia. The discovery beat the previous record held in 1986 by Peruvian Amazonia which included 300 species per hectare.
Despite this major biodiversity, the situation is extremely serious because, of the 202 animal species officially considered to be under threat of extinction in Brazil (IBAMA, Decree No. 1.522 dated 19.12.98), 171 are in the Atlantic Forest.
There is an alarming trend for this number to rise rapidly. In the case of birds, for example, a recent study indicates that at least 40% of the 214 species of endemic birds in the Atlantic Forest are threatened.
The truth is that in a country such as Brazil where biodiversity is little known, there are species that could become extinct even before being catalogued by the scientists and others and which, when discovered, are immediately put on the tragic list of those threatened with extinction. This is the situation with the black-faced lion monkey and the bicudinho-do-brejo, both recently found by researchers less than 200 kilometres from São Paulo, the largest city in South America.
Destruction of the Atlantic Forest
The history of Brazil and the history of the destruction of the Atlantic Forest are bound up with each other and can be explained by each other. The first series of ecosystems to come into contact with the colonizers suffered the consequences of actions by people who had no ties with the area and had no ambition to build a nation. From the pillaging at the start of colonization to its replacement with agricultural practices, the relationship of the Atlantic Forest has always been the same: the policy of destruction and scorched earth.
The plundering of plant species for firewood, coal, food and construction has continued until the present time, leading to the extinction of much of it. Recent studies carried out using satellite pictures show a striking pattern of the replacement of large areas of forest with agricultural development, infrastructural works and urban sprawl.
In 1993, the National Institute of Spatial Research (INPE) and the Atlantic Forest SOS Foundation announced the results of a detailed study on deforestation in the Atlantic Forest spanning ten states, from Rio Grande do Sul to the area south of Bahia, comparing satellite pictures taken in 1985 and 1990. The statistics shocked researchers, government departments and non-governmental organizations alike and were widely reported in the Brazilian and international press. In just five years more than half a million hectares of Atlantic Forest in those states had been wiped out, the equivalent of approximately 400 soccer pitches in land destroyed each day.
The study also showed that as well as being highly concentrated, this destruction had taken place selectively, mainly damaging particular forest formations that comprise the Atlantic Forest. This has also happened to the Araucária Forest in the states of Paraná and Santa Catarina and the forests in the interior of the South and South East regions.
At present, only around 8% of the original area of the Atlantic Forest survives and even that is under threat. It is considered to be the second most threatened ecosystem on the planet, following the almost extinct forests of Madagascar.
Paraná Pines on the Verge of Extinction
The story of the araucaria or Paraná pine (Araucaria angustifolia) could be a sad one, with the species becoming extinct after less than a century of exploitation. Situated within the domain of the Atlantic Forest and scientifically classified as a Mixed Rain Forest, the pine forests originally occurred in a continuous area in the region between the states of Rio Grande do Sul and Paraná, with traces in São Paulo and Minas Gerais. These pine forests are now reduced to approximately 1.2% of the original area.
Studies reveal the existence of new varieties or araucaria occurring in different associations with plant species of major economic importance, such as lauraceae, cinnamon, wild pine, sassafras cinnamon and maté herb. The latter also has an environmental value and is exploited in the groves of the forest.
Currently, of the small numbers remaining of Paraná pine forests, only 40,774 hectares are legally protected in seventeen Conservation Units, amounting to a total of 0.22% of the original area.