EN
Udzungwa Forest-partridge Xenoperdix udzungwensis



Justification

Justification of Red List category
This species is assessed as Endangered because it is known from only three locations within a very small range, in which it is at risk from hunting and habitat loss and degradation. Its small population has been considered stable but numbers fluctuate largely between years.

Population justification
Dinesen et al. (2001) estimate the population to be 3,700 individuals based on the species' range and density in the Ndundulu forest. Butynski and Ehardt (2003) have suggested that this estimate may be too high as in other parts of its range it appears significantly less common. The population may be best estimated in the range 3,000-4,000 individuals (L. Hansen in litt. 2007), roughly equating to 2,000-2,700 mature individuals.

Trend justification
The population has been thought to be stable, with large fluctuations between years (L. Hansen in litt. 2007). However, due to habitat loss and degradation, as well as the additional pressure of hunting, the overall trend is suspected to be decreasing. Deforestation rates within the range have been low over the past three generations (13.29 years), amounting to <5% (Global Forest Watch 2021, using Hansen et al. [2013] data and methods disclosed therein). Population declines are therefore suspected to not exceed 5% over three generations.

Distribution and population

This species is endemic to Tanzania, known only from the Udzungwa highlands (Ndundulu Mountains [Dinesen et al. 1993, 1994], including Mt Luhombero [Butynski and Ehardt 2003, J. Fjeldså in litt. 2004] and Nyumbanitu) and the forest covered top of Chugu Hill in the northern Rubeho Mountains (a northern outlier of Mafwomero Forest [Fjeldså and Kiure 2003, J. Fjeldså in litt. 2004]), c.150 km to the north of the type locality. It seems genuinely absent from the rest of the Udzungwa highlands, despite intensive surveys (D. Moyer and E. Mulungu in litt. 1999, Fjeldså and Kiure 2003, J. Fjeldså in litt. 2004, L. Dinesen in litt. 2007). Genetic analysis suggests that there is no gene flow between the two populations (Bowie and Fjeldså 2005), and their taxonomy is uncertain. Its area of occupancy (AOO) has been estimated at 190 km2, within which it is locally common, with an estimated density of 15-25 birds/km2; following these estimations the total population has been put at c. 3,700 individuals (Dinesen et al. 2001). However, a study in Luhombero Forest indicated that the density there may be lower (Butynski and Ehardt 2003). The population may be best estimated in the range of 3,000-4,000 individuals (L. Hansen in litt. 2007). Although annual population fluctuations make assessing trends difficult, the population is thought to be stable (L. Hansen in litt. 2007).

Ecology

The species inhabits mature montane and submontane evergreen forest, from 1,300 to 2,400 m (L. Hansen in litt. 2007), occurring on forested ridges, steep rocky slopes with forest cover and flatter ground, especially where the understorey is open with scattered Cyperus sedges and ferns (Fjeldså and Kiure 2003, J. Fjeldså in litt. 2004). All locations known for this species are forest with Podocarpus trees (Fjeldså and Kiure 2003), although it does occur in mature forest dominated by other forest tree species (e.g. Hagenia abyssinica) (L. Hansen in litt. 2007). Otherwise its habitat requirements and disjunct distribution remain unclear (Fjeldså and Kiure 2003). It feeds in the leaf-litter on the forest floor, on invertebrates such as beetles (L. Hansen in litt. 2007) and seeds (McGowan 1994). It forages in groups, which are probably families, with 3-13 observed together (L. Hansen in litt. 2007). The main breeding period starts with the onset of the rains in November to March (L. Hansen in litt. 2007). Adults have been seen with chicks in late November, early December and early January (J. Fjeldså in litt. 2004), and immatures are seen almost throughout the year, with a main peak in February to at least July (L. Hansen in litt. 2007). The species roosts in trees, in groups of over 10, four to eight metres above the ground (L. Hansen in litt. 2007)

Threats

The species appears more susceptible to hunting, especially snaring, than once thought (D. Moyer and E. Mulungu in litt. 1999; L. Hansen in litt. 2003; J. Fjeldså in litt. 2003), and although hunting pressure is comparatively low, its demographic effects may be large (Fjeldså and Kiure 2003, J. Fjeldså in litt. 2003). It has been observed on several occasions that local people are efficient at catching the species with snares (L. Dinesen in litt. 2007). Disturbance and hunting (pole cutting, honey collection, traps and snares) are believed to have increased markedly; at least 25 traps and snares were found during surveys for the species conducted in 2002-03 in the Nyumbanitu Forest (L. Hansen in litt. 2003, 2007). However, the species is probably not hunted in the more remote parts of the Udzungwa highlands (L. Hansen in litt. 2003, J. Fjeldså in litt. 2003).
 
The species occurs on a series of high ridges and mountains covered in forests, and the land surrounding these fragments is covered in farmland, plantation forestry, and villages (Jenson et al. 2020). Recent clearing and burning of forest for agricultural purposes has occurred, and large, mostly human-induced, wildfires sometimes occur (Fjeldså and Kiure 2003). As forests decrease in size owing to logging and fires, the species becomes increasingly susceptible to human activities such as hunting (L. Dinesen in litt. 2007). Wide tourist trails have been cut deep into Nyumbanitu forest that are used by lions, hyenas and a non-forest genet Genetta sp., which has been observed predating birds including this species on one occasion (L. Hansen in litt. 2007).
The relatively fast growing human population in Udekwa is increasing the pressure for farmland and meat (L. Hansen in litt. 2007). Payments on new farmland are made only once an income is secured, and farmers prefer areas close to the forest edge. The vicinity to the forest makes it easier for the farmer to get poles and other tools for farming, and wildlife meat and medicine from the trees. Farmers commonly clear land by burning, and control of fires is often lost, as was the case in 2003 (L. Hansen in litt. 2007).

Conservation actions

Conservation Actions Underway
Ndundulu and Nyumbanitu Mountains lie within Kilombero Nature Reserve. Half of the Ndundulu forest, including Mt Luhombero, is inside the Udzungwa Mountains National Park (D. Moyer and E. Mulungu in litt. 1999, J. Fjeldså in litt. 2004). From 2007-2011, a PhD project assessing the effectiveness of the Joint Forest Management programme in the villages of Udekwa and Ifuwa as a model for future resource stewardship schemes was carried out (L. Dinesen in litt. 2007, N. Burgess in litt. 2012).

Conservation Actions Proposed
Evaluate the effects of human disturbance. Determine whether existing ecotourism schemes generate significant revenues, and investigate their effects upon the level of exploitation. Determine the population size, distribution and threats to the Rubeho population. Support implementation of management plans in the Udzungwa Mountains and Udzungwa National Park IBAs. Establish the precise altitudinal range and breadth of habitat-types used, ensuring that disturbance is minimised. Where possible, attempt to halt the clearance of permanent tourist trails through forests, and consider feasibility of establishing buffer zones around forests to protect them from fire (L. Hansen in litt. 2007).

Identification

29 cm. Rufous-and-grey partridge. Rich rufous upperparts barred black. Grey underparts, heavily blotched black. Orange-red throat and eyebrows. Coral red bill, yellow legs and toes. Juvenile undescribed. Similar spp. Scaly Francolin F. squamatus is larger and much darker overall, but this species does not penetrate forest. Voice Whistled teedli teedli. Also a soft low-pitched call and an explosive cry when alarmed. Calls frequently in the mornings, perhaps most regularly during the rainy season, when breeding peaks (L. Hansen in litt. 2007).

Acknowledgements

Text account compilers
Rotton, H.

Contributors
Burgess, N., Dinesen, L., Ekstrom, J., Evans, M., Fjeldså, J., Hansen, L., Keane, A., Moyer, D., Mulungu, E.A., Shutes, S., Starkey, M., Stattersfield, A., Symes, A. & Taylor, J.


Recommended citation
BirdLife International (2024) Species factsheet: Udzungwa Forest-partridge Xenoperdix udzungwensis. Downloaded from https://datazone.birdlife.org/species/factsheet/udzungwa-forest-partridge-xenoperdix-udzungwensis on 23/11/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from https://datazone.birdlife.org/species/search on 23/11/2024.