Jozani biodiversity inventory report 2002 - Coastal Forests of Kenya ...

as plague. Rattus rattus have been reported to cause damage to indigenous forest in New
Zealand (Daniel, 1972) and to coconut palms in Fiji (Williams, 1974).
4. Extraction of forest resources
Timber harvesting is one of the most pressing threats to biodiversity in the study area. For
valuable timber species only a few individuals of Burttdavya nyasica were encountered
during the survey while Milicia exelsa was completely missing. Stumps of Burttdavya
nyasica were encountered in few stands especially in Pandanus-Raphia-Vitex groundwater
forest. The basal areas of many of the timber trees were also very low indicating timber tree
sizes had already been over-harvested. The timber trees in Jozani include Sorindeia
madagascariensis, Terminalia boivinii, Casearia gladiiformis, Macaranga capensis, Bridelia
micrantha, Trichilia emetica, Xylocarpus granatum, Rapanea melanophloeos, Milicia
excelsa, Syzigium cordatum, Syzigium cumini, Albizia adiathifolia, Afzelia qaunzensis,
Burttdavya nyasica, Vitex doniana, Erythrophleum suaveolens and Callophylum inophyllum.
The basal areas for these species are presented in Appendix III. Collection of fuelwood,
building poles and medicinal plants are other activities that may cause loss of species and
therefore pose a threat to biodiversity.
5. Agriculture
Most of the area is unsuitable for farming but Mapopwe and Cheju areas are more fertile and
large areas of Mapopwe have been cleared for farms (Plate 8). Mapopwe area is dominated by
Albizia forest and wildlife there is at risk due to poison which is put into ripe pawpaws and
bananas to kill "pest" animals that destroy crops. The bait was meant to kill monkeys
including vervet, blue and red colobus monkeys. Large areas of forest were cleared and long
coral rock walls are erected to protect farm plots from wild pigs and other animals. Such walls
were also encountered as ruins in secondary forest in Mapopwe.
6. Fire
Man made fires have a great effect on plants and biodiversity in general. Depending on the
intensity and frequency the effects of fire may range from mild where a few fire resistant
species are favoured to severe whereby an area is made completely devoid of vegetation.
Although no event of recent fire was recorded in the study area, the signs of past fires were
noted, especially in the wooded grassland and in the bracken bush. Interviews with the local
people revealed that poachers and honey collectors caused most fires. Fire is also a great
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