Montane reed frog  (Hyperolius castaneus)

Classified as Vulnerable (VU) on the IUCN Red List (1).

Like many frogs within its genus, Hyperolius castaneus displays remarkable variation in appearance (3) (4). The smooth skin of this species is consistently yellow to red underneath, but the colouration and patterning on the back varies considerably. Some have green backs with numerous diffuse dark spots, while others have brown backs, occasionally flecked with black spots. In addition, some forms have an irregular lateral line, running along the side of the body and varying from light to dark (2). Equipped with fairly long limbs and large toe pads, many Hyperolius species are adept climbers (4) (5).

Hyperolius castaneus is found in the Albertine Rift, one of the richest sites for biodiversity in Africa. Its range stretches through eastern Democratic Republic of Congo, western Rwanda, western Burundi, and south-western Uganda (1) (6).

Inhabits swamps in grassland and forest, between 1,600 and 2,850 metres above sea level (1).

Along with many other species in the genus, Hyperolius castaneus is yet to be the subject of a comprehensive study. However, this nocturnal species is particularly noted for its gliding ability (7). In the wet season the reed frogs tend to gather near water, preferably smaller temporary water bodies, where they breed. However, very little is known of their whereabouts outside the breeding season (8). Most, if not all, Hyperolius species from forest habitats deposit eggs in a gelatinous mass on vegetation above water, while some savanna-living species lay their eggs aquatically (5) (8).

Although a relatively abundant species, the distribution of Hyperolius castaneus is severely fragmented and its population is probably declining because of a decrease in the quality and extent of swamp habitat. Habitat conversion for agriculture and encroaching human settlement are thought to be principally responsible for habitat degradation in the Albertine Rift (1)

There are no known conservation measures for Hyperolius castaneus but it is known to be present in at least two protected areas, Bwindi National Park in Uganda and the Virungas National Park in the Democratic Republic of Congo (1).

View information on this species at the UNEP World Conservation Monitoring Centre.

For more information on conservation activities in the Albertine Rift see:

• Wildlife Conservation Society Albertine Rift Programme:
  www.albertinerift.org