Sky-Island Expedition in Mozambique Begins

Krystal Tolley is exploring the “sky islands” of south-eastern Africa. Isolated from the surrounding savanna, these forests on high peaks and ridges contain their own unique wildlife, including many species that are new discoveries. Along with her crew, Krystal hopes to penetrate the veil of mystery around these little-known ecosystems.

The montane isolates or “sky islands” of Mozambique in south-eastern Africa are relatively unexplored, but are potentially rich in biodiversity. Sky islands are isolated granite mountains that rise up from lowland savanna. The sky islands form an important, unexplored linkage between the better-studied Eastern Arc Mountains (Tanzania/Kenya to the north) and the Drakensberg and Cape Fold Mountains (South Africa to the south).

All together, this archipelago of mountains runs more than 4,000 km along the eastern edge of Africa, a distance that equals about half of the length of the continent. Many of the mountains are high enough to draw moisture from an otherwise dry African climate, meaning that they have the right conditions for temperate rain forest to be sustained.

Isolated Mystery

However, because of their isolation, the animals that are specialized to living in forests on top of them will never meet. The animals here cannot cross the hot, dry savanna. The result is that sky islands are expected to be rich in biodiversity, because new species could have arisen in isolation. So, these rarely-sampled montane forests are probably under-estimated in terms of their biological diversity. Through fieldwork supported by National Geographic Society, a team of biologists from South Africa, Mozambique and Europe will be exploring the isolated sky island forests and the surrounding savanna for reptiles and amphibians, to discover and document biological diversity.

This new species of pygmy leaf chameleon (Rhampholeon tilburyi) was recently discovered on the sky island of Mt. Namuli, Mozambique. It forages in the leaf litter on the forest floor by day, and by night, perches in low bushes to sleep. (Photo by Krystal Tolley)

The team will make field identifications and take GPS point localities for cataloging. In addition, DNA bar coding is an important part of this work. Skin samples of the reptiles and amphibians will be collected for laboratory analysis in South Africa and Europe. The DNA bar codes are similar to a unique identification code, contained in the DNA of each species. These codes will assist in identifying any new species found. Comparison of the bar codes between species also means we can determine whether some of the sky island forest species are closely related, possibly from the same ancestral stock.

The field work will start in mid-November 2014 and the team will be in the field for four weeks during the start of the rainy season. Why the rainy season? As you can imagine, that’s the perfect time for locating frogs because they will be very active. For reptiles… we have to catch the right time. At the end of the dry season, prospects are not very good—reptiles are hiding out. At the start of the rainy season, when rains are sporadic, it’s the perfect time. Insects start to emerge, and reptiles begin to forage. So yes… we will get wet, but who cares when there are frogs and lizards about!

October 24, 2014

We are soon on our way… just over two weeks to go. Packing gear, buying supplies and organizing the logistics are the main tasks at this point. Mike Scott, our camp manager, has been hard at work on logistics and has even done “a rekkie” to the area to assess the quality of the roads and access to the forests. In Cape Town, Hanlie and I are busy with shopping and packing supplies, organizing paperwork, getting the vehicle serviced.

We have a long trip ahead. We first will fetch Werner in Port Elizabeth (800 km east of Cape Town), then drive to Johannesburg to meet Gabriela at the airport (flying in from Switzerland). After that, we drive to Maputo and meet with the researchers at the Natural History Museum to discuss collaborations and museum collections. Finally, there will be two additional days of driving north to meet Mike near Mt. Mabu. This montane forest is on the schedule to be surveyed first. Everyone is excited. There are so many possibilities for discoveries on Mabu. Although there have been some very good botanical surveys there, there has not been any full survey for reptiles and amphibians, so the imagination runs wild. At the same time, we are also anxious. We are all thinking… have we forgotten anything?

Read More by Krystal Tolley

Changing Planet


Meet the Author
Krystal Tolley is a National Geographic grantee discovering the diversity of reptiles and amphibians in the montane forests of Mozambique. Krystal and her colleagues are carrying out field surveys of poorly known forests, and following up with DNA barcoding to understand species diversity. This information will feed into conservation assessments to determine if these montane forests are biological hotspots.