| |
|
 |
 |
 |
Biodiversity, forest fragmentation, and extinction |
 |
Osa Conservation |
We have all heard that the Osa Peninsula is one of the world’s most intensely bio-diverse forests in the world. It is in fact a link between North and South America that has an incredible representation of New World flora and fauna. There are 700 known tree species on the Peninsula, and it is estimated that there could be at least 50 or more unclassified and undiscovered trees. Many of these are rare and in danger of extinction, and although many are protected from cutting by law, there are many more which should be protected. There are also many endemic species that have evolved in this region and are found nowhere else on the planet. The Osa is considered one of the most important neotropical areas for endemic species.
Some of the endemic birds which are highly dependant on forest coverage for their survival include the Beryl-Crowned Hummingbird, Baird’s Trogon, Fiery-Billed Aricari, Golden-Naped Woodpecker, Black-Hooded Antshrike, Turquoise Cotinga, Yellow-billed Cotinga, Riverside wren, Black-Cheeked Ant Tanager and the Ramphocelus Costaricensis. These birds are only found on the Osa Peninsula and northwestern Panama. However, since most of western Panama is deforested, the viable populations are limited to the Osa now. On the Osa, these bird populations have been severely diminished over the last few years due to habitat loss from logging.
For a forest and its inhabitants to survive, it must have large contiguous areas to allow for migration and genetic diversity. Unfortunately what is happening now is a process called fragmentation of forest habitat, and this is especially dangerous to the Osa.
Logging, agriculture, monocultural plantations, large hydroelectric dams, mining, road building, house construction and the expansion of towns can cause fragmentation. These and other factors all contribute to the “island effect,” which refers to the severance of biological corridors that provides for migration of species, leading to isolation and genetic degeneration. There are several projects underway, including the sendero de pantera, tapir trail, jaguar trail, and monkey-bridge. The vision is to recreate a series of unbroken habitat and forest-canopy cover to allow these animals to migrate and to prevent incestuous inbreeding and genetic decline. It is not enough anymore to simply protect isolated patches of forest and call it a park. We must connect these “islands” of forests to maintain a healthy habitat. This means that Corcovado National Park will face an accelerated extinction rate if it is not connected to the Talamanca Cordillera. Areas like Puerto Jiménez, Matapalo, Mogos and Piedras Blancas will lose species if the canopy cover is cut and the connection is lost to Corcovado.
We are now in what is called the Sixth Age of Extinction. Other extinction events occurred during the Cretaceous Period, 65 million years ago, the Triassic, 215 million years ago, the Permian, 250 million, the Devonian, 370 million, and the Ordovician, 440 million years ago. The end of the Pleistocene age also marked the loss of many species, which may have been the result of hunting in large organized groups of hominids, and although relatively recent in terms of geologic time, it was not nearly as severe as the other five extinction events that occurred independent of the influence of humanity. The Sixth Age of Extinction occurring now is caused by Homo sapiens sapiens, and the rate that species are disappearing is alarming.
Some estimates of species loss range as high as high as 27,000 per year. What is different in the Sixth Age of Extinction compared to what happened in the past is that the extinction rate is much greater. Further compounding the catastrophe is that we are entering an age of climactic chaos brought about by the uncontrolled release into the atmosphere of the combustion products of fossil fuels, specifically carbon dioxide. When you mix climate change with habitat fragmentation, you get ecological collapse and extinction rates on a global level more than one hundred times background levels.
It is estimated that the current extinction rate of rain forest species is now at least one thousand times greater than normal.
Habitat loss and fragmentation are the leading causes of extinction, and it is undeniable that the Osa Peninsula has suffered from both. Maintaining the bio-diversity of the Osa Peninsula is a priority that can not be overstated. This should catch our attention, but unfortunately this has not entered into the public consciousness, and industry and governments are forging ahead blindly down this road to extinction.
Article courtesy of Joel Stewart - El Remanso |
|
|
|
