Key Biodiversity Areas

Kisarawe District Coastal Forests (7010)
Tanzania, Africa

Site overview


KBA status: confirmed
Global KBA criteria: A1e
Year of last assessment: 2024
National site name: Kisarawe District Coastal Forests
Central coordinates: Latitude: -6.9526, Longitude: 38.9153
System: terrestrial, freshwater
Area of KBA (km2): 374.16206
Protected area coverage (%): 100.00
KBA classification: Global
Legacy site: Yes

Site details


Site description: The range of low hills running south-west from Dar es Salaam to the border of the Selous Game Reserve attracts higher rainfall than the coastal plain and this has resulted in the development of evergreen forest with a poor ground flora on the mainly dry sandy soils. Three Forest Reserves comprise this site: Pugu Hills Forest Reserve (2,180 ha), of which less than 400 ha remains in reasonable condition; Kazimzumbwi Forest Reserve (4,887 ha), of which perhaps only 900 ha can be considered forest; and Ruvu South Forest Reserve (35,000 ha), of which only 10,000 ha can be considered forest. The north-eastern corner of Ruvu South comes within 1 km of the north-western end of Pugu and is only 2 km from the western edge of Kazimzumbwi. Forest composition varies considerably between the three reserves, largely due to the past removal of valued timber, but also reflecting differing soil and groundwater conditions. The only tall (35 m) emergents in Pugu are a few Antiaris toxicaria and Dialium holtzii in the Msimbazi valley. There are even fewer tall emergents in Kazimzumbwi, and Ruvu South is characterized by extensive Zanzibar–Inhambane scrub-forest that may be natural climax vegetation. There are also large stands of riparian forest in Ruvu South, as well as at least two swamps and areas of grass-covered flood-plain. The site has two major railway systems passing through it; the need to protect embankments and cuttings should help ensure some forest remains on the steeper slopes.Vikindu Forest Reserve (1,599 ha, much of which is plantation), to the south of Dar es Salaam, was known to hold Anthus sokokensis, but is so badly degraded that attempts to protect it were abandoned and it has not been included in this site. The close proximity to Dar es Salaam has always placed high pressure on these Forest Reserves. In addition, the Pugu Hills hold one of the world’s largest and most easily accessible deposits of kaolin. Maintaining forest on the hills is important for water-catchment management. Repeated illegal invasions of Kazimzumbwi Forest Reserve have been well publicized. The Wildlife Conservation Society of Tanzania, in conjunction with the Forest Department, CARE and WWF, are running a long-term conservation programme in the area. The extensive plantations of exotic Cassia and Eucalyptus within Pugu should be removed and replaced with indigenous trees. There are kaolin deposits under the Pugu Hills, the exploition of which would necessarily result in destruction of habitat.
Rationale for qualifying as KBA: This site contains the entire known population of Hyperolius ruvuensis. Additionally, one amphibian, 25 birds, four mammals and 22 plants meet legacy KBA criteria and are in need of reassessment.
Manageability of the site: This KBA is entirely covered by protected areas.
Delineation rationale: The KBA delineation includes Ruvu South Forest Reserve (WDPAID: 555623837) and the western portion of Pugu-Kazimzumbwi Nature Forest Reserve (WDPAID: 555721605)

Habitats


IUCN HabitatCoverage %Habitat detail
Forest68
Shrubland31

Threats


Threat level 1Threat level 2Threat level 3Timing
Biological resource useLogging & wood harvestingUnintentional effects: subsistence/small scale (species being assessed is not the target) [harvest]Ongoing
Agriculture & aquacultureAnnual & perennial non-timber cropsShifting agricultureOngoing
Agriculture & aquacultureAnnual & perennial non-timber cropsSmall-holder farmingOngoing
Agriculture & aquacultureAnnual & perennial non-timber cropsAgro-industry farmingOngoing
Natural system modificationsFire & fire suppressionIncrease in fire frequency/intensityOngoing
Transportation & service corridorsRoads & railroadsOngoing
Residential & commercial developmentHousing & urban areasOngoing
Energy production & miningMining & quarryingOngoing
Human intrusions & disturbanceWork & other activitiesOngoing
Natural system modificationsOther ecosystem modificationsOngoing
PollutionGarbage & solid wasteOngoing
Climate change & severe weatherDroughtsOngoing