Measuring up to 30 cm in length and only 0.6 cm in diameter, Boulengerula niedeni (the Sagalla caecilian) superficially resembles a brown earthworm, and the farmers of Sagalla refer to them as ‘m’gnori’ (earthworm). A closer inspection, however, reveals a prominent mouth, a pair of tentacles, and nostrils (or nares). B. niedeni feeds on earthworms, termites, and other invertebrates that live in the soil. While these amphibians rarely move above ground, they are occasionally encountered by farmers when digging on their shambas (small agricultural holdings), and are seen as a sign of rich, fertile soil.

B. niedeni has been found in the greatest numbers on shambas. They are most commonly encountered in the dark moist soil, such as that which is manured by cattle dung. Some farmers have complained that while they used to have both caecilians and black soil, both have now gone due to erosion. The only B. niedeni found in reproductive condition so far have been within the stream banks in the hanging valley of Sagalla Hill. Although it is likely that caecilians are breeding elsewhere on Sagalla, their relatively high densities in the central valley places an important emphasis on this area for their conservation. This same area is under very heavy pressure for agriculture.

Despite considerable search efforts, no Sagalla caecilians have been found within pine or Eucalyptus plantations. Investigations into soil macrofauna (invertebrates such as earthworms, ants, and termites) have shown that the plantations are considerably depauperate, or impoverished, with neither earthworms nor termites present. This is likely to be a result of the toxic nature of the Eucalyptus leaf-litter, which does not support native detritivores. This alone would be enough to inhibit predators such as the Sagalla caecilian. In addition, the soil beneath Eucalyptus is also significantly harder, likely as a consequence of soil erosion and missing soil macrofauna. This makes burrowing much more difficult for subterranean species such as the Sagalla caecilian. Eucalyptus is also famed for its considerable uptake of water. The consequences of exotic Eucalyptus plantations on local ecosystems have been disastrous, drying both streams and soil.

In Sagalla, soil erosion and large stands of exotic Eucalyptus trees are the major threats to the long-term survival of Boulengerula niedeni. Stabilization of soil can be achieved through improved agricultural practices and strategic planting of forested patches. Simply removing Eucalyptus is not a sustainable solution. The area needs replanting with indigenous trees that can provide a permanent reserve for this Critically Endangered amphibian

The Taita Hills represent the northernmost extreme of the Eastern Arc Mountains, a chain of mountains that runs from southeastern Kenya to southern Tanzania and boasts an extremely high diversity of flora and fauna, high levels of endemism, and high threat levels. The area is considered part of the Tanzania-Malawi Mountains Endemic Area. The overriding threat to the biodiversity of the Taita Hills is the loss, fragmentation, and degradation of indigenous forest cover. Indigenous cloud forest in the Taita Hills currently covers an area of about 430 ha, reflecting an estimated 98 percent reduction in forest area over the last 200 years, mainly as a result of clearance for agriculture. Although forest clearance is less widespread at present, past clearance led to increased isolation of the remaining patches, edge effects, soil erosion, and negative hydrological effects. Despite the small size of the 12 remaining indigenous forest fragments, they are of global conservation importance, holding numerous rare and endemic plants and animals. Since many of these species persist in small and very isolated subpopulations, a large proportion is highly threatened and is of immediate conservation concern