Gola Forest Reserve is the largest area of Upper Guinea rainforest in Sierra Leone. It occupies the south-eastern edge of the country and is divided into four sections: Gola North (45,800 ha), Gola East (22,800 ha) and Gola West (6,200 ha) are Forest Reserves, while Tiwai Island (1,300 ha) is a Game Sanctuary. Tiwai Island is situated in the Moa river, 10 km north-west of Gola West. Gola West and East are contiguous, separated only by the Mahoi river and a road, while Gola North lies about 5 km north-east of Gola East. Gola North is fairly hilly, with most land lying above 300 m and the highest point at 475 m. The main river draining Gola North is the Mogbai, and its catchment spans the centre of the reserve. This river discharges into the Mano river, which runs along the border with the Republic of Liberia. Gola East, Gola West and Tiwai are low-lying with swampy areas and a few hills. Bagra hill (150 m) is the highest point in Gola East. Dominant canopy tree species include Heritiera utilis and Cryptosepalum tetraphyllum with Erythrophleum ivorescens, Lophira alata, Brachystegia leonensis and Didelotia idae occurring in the lower strata. Canopy height is mainly between 30–35 m, with emergents reaching 50–55 m.
See Box and Tables 2 and 3 for key species. To date, 274 species have been recorded, including 14 species of global conservation concern. Six of these have not, so far, been recorded elsewhere in Sierra Leone. The reserve holds the largest number of nesting sites of Picathartes gymnocephalus in the country (36 nesting sites, comprising 204 active nests). Groups of up to 12 Agelastes meleagrides have been recorded. The forest holds nearly 90% of Sierra Leone’s species of the Guinea–Congo Forests biome.
Non-bird biodiversity: Gola Forest supports significant populations of the following primates: Pantroglodytes verus (EN), Procolobus badius (VU), Colobus polykomus (LR/nt), Cercocebus atys (LR/nt) and Cercopithecus diana (VU). It is also a refuge for other large mammals, including Loxodonta africana cyclotes (EN), Cephalophus zebra (VU), C. jentinki (VU), C. maxwelli (LR/nt), C. niger (LR/nt), Hexoprotodon liberiensis (VU) and Hyemoschus aquaticus (LR/nt).
Pressure/threats to key biodiversity
Two areas in Gola North and Gola East have been proposed as Strict Nature Reserves. Tiwai Island is to be included in the Gola Forest management plan. Up until the start of the civil war in 1991, commercial logging by timber companies had resulted in the degradation of sections of Gola. Large-scale logging operations stopped, however, during the war. Currently, the indiscriminate use of chain-saws, especially by difficult-to-control, unlicensed private individuals, is probably the most important threat, while logging may restart as the war winds down. Gold and diamond prospecting occur along the streams and riverbanks within the reserve, creating disturbances to, and pollution of, the aquatic ecosystem. Hunting is also prevalent; this activity is one of the major sources of income and protein for many of the inhabitants in the area. Hunting gangs from neighbouring Liberia cross the borders to hunt and smuggle out large quantities of bush-meat. Encroachment from agricultural activities, although limited, needs to be controlled. The extent to which these activities have continued during the civil war is unknown, but it is likely they have been considerably restricted.