Justification of Red List Category
This species is classified as Vulnerable since habitat loss and range contractions suggest its small population is undergoing a decline, which is expected to accelerate to a rapid pace given projected rates of habitat loss and the impacts of climate change.
Barnes (2000) estimated the population to be 2,500-6,500 individuals, roughly equivalent to 1,700-4,300 mature individuals. In view of substantial range reductions since Barnes's assessment, and assuming concomitant population declines, Little (2015) used a conservative estimate of a 20% population decrease, estimating the population at 2,000-4,800 individuals. Estimates based on extensive field work to determine the summer breeding range of this species, and using species range figures and average home range sizes, have resulted in population estimates of 607-1,730 individuals, approximately equating to 424-1,210 mature individuals (Pietersen et al. 2018).
The species's population is inferred to be declining due to ongoing loss and degradation of its grassland habitat (Pietersen et al. 2018). Habitat loss through rangeland degradation and conversion to agriculture is ongoing (Pietersen et al. 2018). Survey work does suggest, though, that the population may be stable in some local patches (R. Colyn in litt. 2017), so past declines are tentatively suspected to be moderately rapid. The rate of decline is expected to increase in the next ten years, with climate change potentially impacting 90% of the species's range by 2050 (R. Colyn in litt. 2017).
Hemimacronyx chloris is a resident and partial migrant of eastern South Africa and, marginally, eastern Lesotho (Clancey 1990; Peacock 2006; Pietersen et al. 2018). The core range is centered on the eastern escarpment and Drakensberg Mountain foothills in the Mpumalanga, KwaZulu-Natal and eastern Free State provinces, with small isolated populations occurring further south in the north-east Eastern Cape Province.
Recent survey work has located breeding individuals from Dullstroom (Mpumalanga Province) in the north though to Cathcart (Eastern Cape Province) in the south, with the highest densities of birds being found in the eastern Free State and northern Mpumalanga provinces, with relatively high densities in southern Mpumalanga and the Eastern Cape provinces too (R. Colyn in litt. 2017). Local patches across these areas may contain stable populations (R. Colyn in litt. 2017). Predictive niche modelling suggests that most of the potentially suitable habitat for this species is already occupied (Pietersen et al. 2018). The non-breeding range remains poorly known, but non-breeding individuals have been recorded from Suikerbosrand Nature Reserve in Gauteng Province, Secunda in Mpumalanga Province, and in the KwaZulu-Natal Province coastal region (Clancey 1990; Peacock 2006; Little 2015). Its range has decreased, and it may now occupy a breeding area of approximately 45-230 km2 (Pietersen et al. 2018), with this range reduction believed to reflect concomitant population declines.
The species holds breeding territories in upland undulating grasslands, favouring lush, almost meadow-like conditions, where it frequents areas of tussock and grassy slopes (Clancey 1985, 1990, 1997; Peacock 2006). It avoids overgrazed or recently burnt areas (Jansen et al. 1999), but will forage in burnt areas if unburnt areas are available nearby to nest in (D. Pietersen, I. Little and R. Jansen in litt. 2016). Modelling revealed that this species reacted negatively to increasing grass cover, suggesting a needed for controlled grazing post burning to open up patches for feeding and nesting (Maphisa et al. 2019). Clutch-size is usually three, laid during the rains. After breeding, most individuals disperse to lower-lying areas on either sides of the escarpment, although some individuals remain on the breeding grounds (Clancey 1985, 1990, 1997; Peacock 2006).
Historical population reductions have been attributed to habitat loss and fragmentation as a result of intense grazing as well as too frequent or too infrequent burning, and conversion of habitat to crop agriculture. Present threats include agricultural intensification, unsuitable fire regimes, intensive grazing (Jansen et al. 1999) and conversion of suitable habitat to open-cast coal mines (Little et al. 2013; D. Pietersen, I. Little and R. Jansen in litt. 2016; R. Colyn in litt. 2017). Rapid afforestation of montane grasslands is now considered less of a threat, although previous afforestation and the practice of planting copses of exotic trees such as Eucalyptus near homesteads has led to the expansion of the range of avian predators, mainly hawks Accipiter sp., and particularly Accipiter rufiventris, into the grassland biome where they were previously absent (D. Pietersen, I. Little and R. Jansen in litt. 2016). The extended display flight and bright colouration of the male Yellow-breasted Pipits may make them particularly susceptible to predation by avian predators (Pietersen et al. 2018). Future climate change is predicted to have a large negative impact on this species's range, with potentially 90% of the range impacted by 2050 (Simmons et al. 2004; R. Colyn in litt. 2017).
Conservation Actions Underway
The species occurs in several publicly-owned nature reserves, of which Verloren Vallei Provincial Nature Reserve holds the most important population (c.250-500 individuals) (D. Pietersen, I. Little and R. Jansen in litt. 2016). The proposed Grassland Biosphere Reserve, centred around Volksrust and Wakkerstroom, is also estimated to hold a significant proportion of the global population (250-500 individuals) (D. Pietersen, I. Little and R. Jansen in litt. 2016). In Lesotho, the Sehlabathebe National Park supports c.20 pairs (D. Pietersen, I. Little and R. Jansen in litt. 2016). The Endangered Wildlife Trust is actively attempting to secure protected areas of suitable grassland for this and associated threatened bird taxa in the Wakkerstroom-Memel region, as well as around Verloren Vallei Nature Reserve (I. Little in litt. 2016). A population genetic study is underway to determine whether there is still gene flow between the purportedly isolated populations.
16-18 cm. Yellow-and-brown pipit. Unmistakable breeding plumage with bright yellow underparts. Juvenile and non-breeding individuals drab with streaked underparts, but still show yellowish wing-linings. Similar spp. Much larger Yellow-throated Longclaw Macronyx croceus has black breast-band. Voice Rapid, staccato chip chip chip and subdued suweep. Hints Usually in pairs, but forms small flocks outside the breeding season.
Text account compilers
Colyn, R., Ekstrom, J., Jansen, R., Little, I., Pietersen, D., Pilgrim, J., Shutes, S., Symes, A., Taylor, J. & Westrip, J.R.S.
BirdLife International (2022) Species factsheet: Hemimacronyx chloris. Downloaded from http://www.birdlife.org on 29/11/2022. Recommended citation for factsheets for more than one species: BirdLife International (2022) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 29/11/2022.