Juveniles also have a golden-brown coat, but the color changes to dark brown in young males when they reach two to three years of age.

[4][5] The horns of the adult males are 50–87 cm (20–34 in) long, strongly ridged at their bases and are curved at the tips.

Known predators are humans, lions, crocodiles, cheetahs, wild dogs, hyenas and leopards.

[2] Yearling Nile lechwes are often infected by warble flies, which can make them unhealthy and result in high mortality rates.

Wild rice is thought to be a preferred food at the start of the flood season, while a larger proportion of swamp grasses are consumed when the waters recede.

In Sudan, the majority of the population occurs in the Sudd swamps, and in the Machars near the Ethiopian border in smaller numbers.

In Ethiopia occurs in the southwest, in Gambela National Park, but in very less numbers possibly due to human settlement and habitat degradation.

The habitat of the Nile lechwe has been severely affected by civil wars, human displacement and resettlement, firearm attacks and increased hunting.

In 1983, aerial surveys gave a total population estimate of 30,000-40,000 individuals, of which 95 percent were concentrated in the Sudds and the rest occurred between Sudan and Ethiopia.

[8] In 2007, the population of the Sudd region was estimated to be of 4,291 animals, indicating that the species has declined rapidly since the previous survey in 1983.

In South Sudan, Nile lechwe populations occur in three protected areas : Zeraf Game Reserve, that extends over 9,700 km2 (3,700 sq mi) along the Bahr el Zeraf; Fanyikang Game Reserve, north of Bahr el Ghazal, covering over 480 km2 (190 sq mi); and Shambe National Park, that stretches over 620 km2 (240 sq mi) along Bahr al Jabal.