Tuesday, June 30, 2015

Madagascar's Stone Forest. Tsingy de Bemaraha.

Tsingy de Bemaraha (Photo from Tourism On The Edge)

Madagascar is not only known for its flora and fauna but also for one very unique bit of landscape.  In fact, it is so unique, that ony a few similar formations exist outside of Madagascar and none are as spectacular.


Encompassed by the boundaries of Tsingy de Bemaraha National Park is the largest limestone forest in the world.  The park centers on two geological formations - the Great Tsingy and the Little Tsingy. Together with the adjacent Tsingy de Bemaraha Strict Nature Reserve, the National Park was designated a World Heritage Site by the UNESCO in 1990.  The reserve is not open to the public.

Photo by Steven Alvarez
The word tsingy is indigenous to the Malagasy language as a description of the karst badlands of Madagascar.  I've seen it translated to mean everything from *walking on tiptoes* to *where one cannot walk barefoot*.   Whatever the real translation is, there is no doubt the word aptly describes the needle-like rock formations which are so sharp, they can easily cut through human flesh.

The unusual stone formations of Tsingy de Bemaraha are a type of karst system, a landscape formed from porous limestone that was dissolved, scoured, and shaped by water.

The formation of these unusual rocks actually began some 200 million years ago when layers of calcite accumulated at the bottom of a Jurassic lagoon, forming a thick limestone bed. Later tectonic activity elevated the limestone, and as sea level fell during the Pleistocene ice ages, even more of the limestone was exposed.

The limestone seabed rose to create a plateau which was, little by little, eroded by monsoon rains which washed softer rocks away and left tougher rocks standing.

Researchers believe that groundwater infiltrated the great limestone beds and began to dissolve them along joints and faults, creating caves and tunnels. The cavities grew, and eventually their roofs collapsed along the same joints, creating line-straight canyons called grikes, up to 400 feet deep and edged by spires of standing rock. Some grikes are so tight that a human traveler has difficulty passing through them; others are as wide as an avenue.

Tsingy de Bemaraha is delimited to the east by the abrupt Bemaraha Cliffs, which rises some 300 to 400 meters (1312 feet)  above the Manambolo River valley and extends several tens of kilometers from north to south. The western slopes of the massif rise more gently, and the whole western region of the reserve forms a plateau with rounded hillocks which slope away to the west. To the north undulating hills alternate with limestone extrusions, while in the south extensive pinnacle formations make access extremely restricted.

Despite the impressive numbers of indigenous plant and animals species there are in Madagascar, I read somewhere that 90% of the land that was once forest was slashed and burned so it could be used by man for agricultural purposes.  With so many ecosystems disintegrating, it's no wonder that so many of Madagascar's fauna and flora are listed as threatened species!

Isolated and inhospitable, this huge collection of razor-sharp vertical rocks looks like the last place where wildlife would thrive.  But ironically, it is because it is the one place that man has not been able to slash and burn, that makes this place a paradise for plants and animals.

The park’s canyons, gorges, undisturbed forests, lakes and mangrove swamps have been and continue to be ideal refuges for both flora and fauna.  The isolation from other species, on the island, has resulted in an 85% rate of edemisim here and 47% are even local endemic!  This is simply astonishing given the incredible number of plant and animal species that can be found here.

Photo by Frans Lanting.
The flora, in Tsingy de Bemaraha, has a high local endemism rate. The western part is principally covered by deciduous dry forests, which are particularly well adapted to the extreme changing climate conditions of the area. The eastern section is formed by grassy savannas and lowland bushes. Unbelievably, there are actually dense tropical forests inside the canyons as it is very humid among the tall tsingy formations!

Tsigny de Bamaraha is also home to 11 lemur species, more than 100 bird species and 45 reptiles and amphibians which are all local endemic.

An interesting aspect about the flora and fauna here is that they inhabit different parts of the rock forest.




A gorgeous photo of a pair of Decken's sifaka
taken by Steven Alvarez.
At the tops of the rock formations,  there is little soil and no shelter from the sun. Here, temperatures often soar above 90°F, and plant and animal life is restricted to creatures that can resist desiccation or move between the pinnacles and the canyons. Lemurs like the white-furred Decken's sifaka and the brown lemur call this area home - leaping from one stone spike to another as they travel between fruit tress.   In slots and crevices, you'll find lizards and insects living among drought-tolerant xerophytes—euphorbias, aloes, spine-covered Pachypodium, and other plants that drop long, cable-like roots into the rock searching for water.

In the middle ranges of the stone forest, more niches appear in the canyon walls. Large fruit bats and dark vasa parrots roost here.

On the stone forest floor,  where water and soil collect, that the environment is richest.  Here, tropical hardwoods, orchids, giant snails, chameleons, snakes and rats are few of the animals that can be found here.  Where there are small animals, there is also a predator - in this case, the fossa.

Last, but not least, the forest is also home to a labyrinth of underground caves and passages where insects and aquatic live in the shelter of the dark.

From what I gather, it's at least an eight hour drive, over some pretty rough terrain, to just get to the park.  And from all accounts I've read, it's not easy making your way through the park - there's at least one rope bridge to cross and in some parts, harnesses may be required.   I'm also not sure how much time we'll actually be able to spend here so I hope we'll at least get to see the highlights.  Whatever is in store for us, I'm excited to experience this truly unusual and very special place!
 

If you want to find out more about Tsingy de Bemaraha, I recommend reading this National Geographic article by Neil Shea.  And while you're at it, admire the wonderful photos taken by Steven Alvarez, who accompanied Shea on the NatGeo expedition to Tsingy de Bemaraha.