The long-billed tailorbird is under threat from forest destruction and fragmentation, and although the extent of protected forest in the East Usambaras has increased in recent years, unprotected forest is still under pressure from mining, cultivation, pole-cutting and firewood collection (3) (5), and habitat degradation still continues even within Forest Reserves (11). In 2000, the population in the Amani Nature Reserve in the East Usambaras was estimated at just 150 to 200 (4), although more recent work suggests this may be a slight underestimate (7). The population in Nilo Nature Reserve, East Usambara Mountains, which was initially discovered in 1996 (9), is currently being investigated, and preliminary data suggest that the entire East Usambara population will be higher than previously thought (12). The population of the Njesi Plateau in Mozambique is unknown, but is likely to be small (2) (3) (6).
Although the long-billed tailorbird may not be overly affected by disturbance within the forest, since it tends to favour canopy gaps, the introduced tree Maesopsis eminii may present a threat, as it regenerates very rapidly in forest gaps, quickly closing them. The removal of vegetation such as Lantana bushes bordering tea estates and its replacement with Eucalyptus plantations may also remove potential habitat (7). The species’ low population density, its restriction to just two sites, and the small amount of suitable remaining habitat make the long-billed tailorbird particularly vulnerable to extinction, although there are hopes that it may yet be found in other forest areas in the region (3).