North Nandi Survey
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ASSESSING THE CONSERVATION STATUS OF AVIFAUNA AND THE FOREST HABITAT OF NORTH NANDI IMPORTANT BIRD AREA, KENYA AUTHORS: Simon Musila, Alex Syingi, Nickson Sajita A Project Funded by African Bird Club (ABC) FINAL REPORT: ASSESSING THE CONSERVATION STATUS OF AVIFAUNA AND THE FOREST HABITAT AT NORTH NANDI IMPORTANT BIRD AREA, KENYA Simon Musila1, Alex Syingi2, Nickson Sajita3 1 National Museums of Kenya, Mammalogy Section, P. O Box 40658, GPO 00100 Nairobi-Kenya. Tel. +254-020- 3742131/61-64 ext 242/3. Fax. 3741424, 3741049. Email: [email protected], [email protected] 2 National Museums of Kenya, Ornithology Section, P. O Box 40658, GPO 00100 Nairobi-Kenya. Tel. +254-020- 3742131/61-64 ext 242/3. Fax. 3741424, 3741049. 3 Kakamega Environmental Education Program (KEEP), Naturalist and guide-Kakamega Forest Important Bird Area, Kenya. SUMMARY: North Nandi Forest Important Bird Area is one of the most sites for the conservation of globally-threatened Chapin’s Flycatcher Muscicapa lendu in Kenya. In between July and October 2009, avian surveys were conducted in the eastern part of this forest to assess the conservation status of Chapin’s Flycatcher and other avifauna. Five different transects about 500M from each other and 3-3.5Km in Length were used. A total of 108 bird species were recorded which were 68% of 160 recorded in 1999. Out of 108 species, 33 were forest specialist (FF), 37 generalist (F) and 37 visitors (f). 21 Afro- Tropical Highland Biome species recorded in the survey represented 62 % (21/34) of 34 in the past, while 21 Guineo-congolian Forest Biome forest bird species recorded represented 88% (21/24) of the 24 recorded in this forest in 1999. The globally threatened Chapin’s Flycatcher was not recorded in this study. Five individuals of globally- threatened Turner’s Eremomela Eremomela turneri were recorded in Ngatatia-Kapkuto transect foraging on top of Croton megalocarpus tree. Threats to forest included cattle grazing, firewood collection and extraction of building/fencing poles and timber. No evidence of recent large-scale commercial logging and charcoal burning was recorded in the eastern part. The high species riches of FF, biome-restricted species in the small area (157ha) surveyed in the current study probably indicates that North Nandi Forest has faced minimal habitat degradation for the last 10 years (1999-2009). We therefore, recommend additional research on biodiversity of this forest, improved patrols by Kenya Forest Service (KFS) guards to reduce illegal forest exploitation and engagement of the surrounding local community to undertake activities which sustainably improve livelihoods and forest conservation. INTRODUCTION: North Nandi Forest Important Bird Area (IBA) is a strip of high- canopy Forest Reserve on the edge of the Nandi escarpment, Rift Valley, Kenya. Biogeographically, the forest is transitional between the lowland forest of west and central Africa and montane forests of the central Kenya highlands (Bennun and Njoroge, 1999). The forest belongs to the Kakamega and Nandi forests Secondary Area of endemism, defined by the presence of the globally threatened and restricted-range 2 Chapin’s Flycatcher Muscicapa lendu (Stattersfield et al. 1998; Bird Life International, 2000). Avifauna is similar to that of the adjacent Kakamega Forest mostly comprising of Guinea-Congo forests (24 out of 43 Kenyan species) and Afro-tropical Highland biomes (34 out of 67 species) species; and abound 160 species have been recorded in the past (Bennun and Njoroge, 1999; Zimmerman et al. 1996). It is one of the important sites in Kenya for globally threatened Chapin’s Flycatcher (vulnerable). Species of regional concern includes African Green Ibis Bostrychia olivacea, African Crown Eagle Stephanoaetus coronatus, Red-chested Owlet Glaucidium perlatum, Thick-billed Honeyguide Indicator conirostris, Least Honeyguide Indicator exilis, Grey-chested Illadopsis Kakamega poliothorax, Yellow-bellied Wattle-eye Dyaphorophyia concreta (all vulnerable) and Southern Hyliota Hyliota australis (Zimmerman et al. 1996). The main threats to the forest habitat include illegal timber extraction, charcoal burning, forest grazing and unsustainable removal of forest products (Ng’weno et al., 2004; Musila, et al., 2005; Bennun and Njoroge, 1999). Such activities are likely to reduce significantly or locally exterminate populations of avian species highly sensitive to habitat disturbance. Overall Aim The main goal of this study was to assess avifaunal richness and abundance, conservation status of Chapin’s Flycatcher and threats to forest habitats of North Nandi Forest IBA. Specific Objectives were; 1. Determine the current status of globally threatened and restricted-range Chapin’s Flycatcher. 2. Investigate the bird species richness and abundance. 3. Investigate the current threats to the avifauna and forest habitats. 4. Recommend the appropriate conservation strategy to conserve birds and their habitats. 3 METHOD AND MATERIALS Study area. This project was conducted in North Nandi Forest which occurs in between 00°00’ S 35° 00’E in Rift Valley Province of Kenya at an altitude of 1700-2130m (Fig 1). This area receives about 1500mm of rainfall annually, and has soils which are well drained. The forest is an Important Bird Areas and legally protected as a Forest Reserve in Kenya under the management of Kenya Forest Service (KFS). This study was conducted in the eastern part of the forest in between July and October 2009, during the wet season in Kapchepkok area of North Nandi Forest. In 1999, the gazetted forest area covered 10,500ha which included 8000ha of indigenous close-canopy forest and 2,500 ha of cultivation, grasslands, plantation and tea fertile (Bennun and Njoroge, 1999). Figure 1: Map of Kenya and the study area from Bennun and Njoroge (1999) 4 Bird Surveys: Birds were surveyed using transects, which were routes used by the locals grazing in the forest, collecting firewood or accessing the western part of the forest. Five transects (Kamokuywo-Chesombe-3.5Km; Ngatatia-Kipsamoite-3.0Km; Kamokuywo- Epeso Hill-3.0Km; Ngatatia-Kapkuto-3.0Km & Singoro-Irewa-3.2Km) were established on the eastern side of North Nandi Forest on the side of Kapsisiywa (Fig 1), identified in four villages (Kamokuywo, Chesombe, Ngatatia and Singoro) in Kapchepkok Sub- location. The transects were about 500M from each other and 3-3.5Km in Length into the forest. The start of each route was marked using GPS. Three observers surveyed birds from dawn (6:30am) and ended at 10:00am, when bird activities declined. All bird seen or heard calling within 50 M from observes from both sides of the transect were recorded including the species, number and type of contact (Bibby, et al.,1998; and Bibby. et al., 1992). To compile a comprehensive checklist of birds from the forest we recorded any new spices encountered in the forest after the end of transect surveys and beyond 50M from observers. Human activities such as cattle grazing, logging and firewood collection were noted along each transect and some locals were interviewed about utilization of forest products and their participation in the conservation of North Nandi Forest. Data analysis: Data for the two surveys (July and October) for the five transects was combined and analyzed because it covered the same section of the North Nandi Forest. A checklist of birds was prepared reflecting avifaunal composition of the IBA. Bird species were categorized into their dependence (forest specialist, generalist and visitors) on the forest following classifications provided by Bennun et al., (1996). Densities of Forest Specialists (FF) and Forest Generalists (F) were calculated by dividing the total number of individuals of each species recorded by the total area of the five transects. The total area surveyed was 157ha (transect width (50M one side *2=100M)* total length of five transects 15.7KM (15700M) =1,570,000M2/10,000 M2 (1ha-10,000M2). Out of 10,500ha of North Nandi Forest in 1999 we estimated visually that 6000 ha (25% (2000 ha lost since 1999) was the remaining undisturbed primary habitat suitable for forest specialists birds. We also estimated that 8000ha of existing forest in 2009 was suitable for forest generalist birds. The population size of forest specialist and generalist birds was estimated by multiplying the calculated density of each species with the remaining primary (6000ha) and secondary (8000ha) habitats. 5 RESULTS Species richness: A total of 108 bird species were recorded in the five transects inside North Nandi Forest in July and October 2009 surveys (Appendix 1). A total of 68 species were recorded in Ngatatia-Kipsamoite transect, 57 in Kamokuywo-Chesombe, 55 in Ngatatia-Kapkuto, 51 in Kamokuywo-Epeso Hill and 41 in Singoro-Irewa. A total of 33 forest specialist (FF), 37 generalist (F) and 37 visitors (f) birds were recorded in the five transects (Table 1). Table 1: Summary of different forest birds recorded in North Nandi Forest. FOREST BIRD CATEGORY TOTAL PERCENTAGE SPP (%) 1 Forest Specialist (FF) 33 31 2 Forest Generalist (F) 38 35 3 Forest Visitors (f) 37 34 TOTAL 108 100 Species Abundance: Using bird densities per ha. as indicators of bird abundance in the forest: Cabanis Greenbul Phyllastrephus cabanisi a forest specialist was the most abundant followed by Buff-throated Apalis Apalis rufogularis, Stuhlmann's Starling Poeoptera stuhlmanni, Olive Sunbird Nectarinia olivacea, Dusky Tit Parus funereus and Brown-chested Alethe Alethe poliocephala (Table 2). Yellow-whiskered Greenbul Anthropadus