The zoogeography of the montane forest avifauna of eastern Tanzania - Biogeography and Ecology of the Rain Forests of Eastern Africa - page 206

Table 10.1. (cont.)

Montane Forest Group
(following Moreau, (following this Number of

b

Forest Country 1966t chapter) species

Mount Thyolo Malawi TN SM 17

Mountains west of L. Edward Za1re ECO AR 70

Mufindi Tanzania TN EC 34

Nguru Tanzania TN EC 31

Nguruman Kenya KE CEA 22

North Pare Tanzania TN CEA 27

Nyika Plateau Malawi/Zambia TN EC 31

Nyungwe Forest Rwanda ECO AR 60

Obudu Plateau Nigeria CAM CAM 35

Rumpi Hills Cameroun CAM CAM 35

Rwenzori Uganda/Za1re ECO AR 64

Simien Mountains Ethiopia AB ETH 10

South Pare Tanzania TN CEA 23

Southwest Ethiopia Ethiopia AB ETH 20

Taita Hills Kenya TN None 14

Ufipa Plateau Tanzania None None 16

Uluguru Tanzania TN EC 41

Ukaguru Tanzania TN EC 28

Usambara Tanzania TN EC 41

Virunga Volcanoes Rwanda/Za1re/U ganda ECO AR 56

Vumba Zimbabwe soz soz 16

Note: aMontane Forest Groups following Moreau (1966): AB, Abyssinia; ANG, Angola; CAM, Cameroun; ECO,
East Congo; KE, Kenya; SOZ, South of Zambezi; TN, Tanzania.
b Montane Forest Groups following this chapter: AR, Albertine Rift; CAM, Cameroun; CEA, Central East Africa;
EC, East Coast Escarpment; ETH, Ethiopia; SM, South Malawi; SOZ, South of Zambezi.

The 50 forests considered in this analysis have
a combined total of 163 montane forest species
(following the definiion of a montane forest spe-
cies outlined in the Inroducion to this chapter).
In order to assess the biogeographic affiniies of
these orests in terms of the species composiion
of their montane bird communiies, a cluster
analysis was performed on these data, based on
Sorensen's Index .), which is given by:
, = 2j
a+b
where a= the number of species in forest 1,
b = the number of species in forest 2, j = the
number of species common to both forests.
The index ranges from zero for two forests with

no species in common, to one for two forests with
all species in common. In Figure 10.1 a cluster
analysis dendrogram is presented. In terms of
their montane bird species composition these for-
ests fall into seven major Groups (indicated in
capital letters on Figure 10.1). In addiion five
areas, the Taita Hills, Mahale Mountain, Ufipa
Plateau, Angolan Highlands and Angolan Escarp-
ment, have an unusual assemblage of species and
do not fit into any of the seven Groups. Of these
major Groups, it can be seen from Figure 10.1
that two of them, Cameroun and Ethiopia, are
paricularly disinct. The remaining ive Groups
all cluster between Q, 0.6 and 0.7. Within each
Group the Tl value between montane forest avi-
faunas is almost always between 0.8 and 1.0.