PRIMATES

Full screen Primates Id code: amd302

Galagonidae
Otolemur garnettii

(Ogilby, 1838)

(Eng) Garnett's or small-eared greater galago

(Fre) Galago de Garnett

Taxonomic notes

Placed in a separate genus (together with its sibling O. crassicaudatus) by Groves (1974), it is sometimes included in Galago senegalesis (Doyle & Bearder, 1977).

IUCN threat category

Lower Risk, near threatened (LR: nt).

Available information

Literature available on the ecology of this species is limited. Behavioural aspects of the species' ecology were thoroughly studied in the Diani Beach Forest and at Gedi (Kenya) (Nash, 1986; Nash & Harcourt, 1986). A captive study of its reproduction was carried out by Izard & Simons (1986). General information on its ecology and distribution is found in several authors (Kingdon, 1997; Masters, 1985, 1988; Nash et al., 1989). Status and threats are discussed in Oates (1996).

Known extent of occurrence

The range of O. garnettii extends along the coastal regions of east Africa, from the Juba River in Somalia to the Rivuma River in Tanzania, including the islands of Pemba, Mafia and Zanzinbar (Wilson & Reeder, 1993; Nash et al., 1989). Its distribution map was obtained from Nash et al. (1989), but subsequently revised and updated on the basis of the information in Kingdon (1997) to match the river network (Fig. 2.2.12.a).

Categorical-discrete (CD) distribution model

This species is restricted to coastal, riverine and highland forests; it is also found in riverine galleries within Acacia woodland areas (Nash et al., 1989; Doyle & Bearder, 1977; Kingdon, 1997).

Based on these environmental preferences, the following scores were assigned (Fig. 2.2.12.b) (2.2.12.a):

Score ^(*)
1	Forests.
2	Forest mosaics.
3	Savannas and croplands.
^{(*) Scores increased for vegetation types occurring inside a 1-km buffer around permanent water.}

suitable		moderately suitable		unsuitable		Total
km²	%	km²	%	km²	%	km²	%
16 340	2	218 411	28	532 249	69	767 000	100

Tab 2.2.12.a Cumulative size (km²) of areas pertaining to each environmental suitability class within the Extent of Occurrence.

	Number Patches (NP)	Mean Patch Size (MPS) km²	Patch Size SD (PSSD) km²	Largest Patch Index (LPI) %	Mean Shape Index (MSI)	Area-Weighted Mean Shape Index (AWMSI)
suitable	283	57	102	0.51	1.14	1.55
moderately suitable	491	442	5 400	51	1.57	21.87
Total AO	431	541	6 364	55.79	1.58	22.76

Tab 2.2.12.b: Area of Occupancy fragmentation indexes.

Probabilistic-continuous (PC) distribution model

The output of the probabilistic-continuous (PC) distribution model is shown in Fig. 2.2.12.c.

Validation

No occurrence of the species within the four sample areas.

Comments and conservation issues

As for Galagoides zanzibaricus which is largely sympatric, this species has a wide EO but its actual AO is restricted to the remnants of coastal forests and to gallery and riverine forests. Only 30% of the EO is classified as potential AO and the fragmentation indexes indicate an intricate network of areas with very irregular shapes (AWMSI). The river network helps to maintain relatively high continuity of suitable areas (LPI = 55.79%). The PC model does not restrict the EO to the forest areas along rivers and wrongly distributes a much higher suitability over most of the EO. Almost 12 % of the total AO is included in protected areas.

SUITABILITY CLASS	inside	outside	Total
suitable	0.25	1.88	2.13
moderately suitable	3.87	24.61	28.48
unsuitable	10.56	58.83	69.39
Total	14.69	85.31	100

Tab 2.2.12.c: Percent of environmental suitability classes within EO (as obtained from the categorical-discrete distribution model) inside and outside the protected areas.

References

Doyle G.A., Bearder S.K. (1977). The Galagines of South Africa. In: Bourne G.H. (Ed.). Primate Conservation. Academic Press, London and New York; chap. 1: 2-37.

Groves C.P. (1974). Taxonomy and phylogeny of prosimians. In: Martin R.D., Doyle G.A., Walker A.C. (Eds). Prosimian Biology. University of Pittsburgh Press, Pittsburgh.

Izard M.K., Simons E.L. (1986). Management of reproduction in a breeding colony of bushbabies. In: Else J.G., Lee P.C. (Eds). Primate ecology and conservation. Selected Proceedings of the 10th Congress Int. Primatological Society, Nairobi, Kenya (July 1984). Cambridge University Press, Cambridge, U.K: chap. VI.6, 315-324.

Kingdon J. (1997). The Kingdon field guide to African Mammals. Academic Press, London and New York: Natural World.

Masters J.C. (1985). Geographic distributions of karyotypes and morphotypes within the Greater Galagines. Folia Primatol.: 46, 127-141.

Masters J.C. (1988). Speciation in the greater galagos (Prosimii: Galagidae): review and synthesis. Biol. J. Linn. Soc.: 34, 149-174.

Nash L.T. (1986). Social organization of two sympatric galagos at Gedi, Kenya. In: Else J.G., Lee P.C. (Eds). Primate ecology and conservation. Selected Proceedings of the 10th Congress Int. Primatological Society, Nairobi, Kenya (July 1984). Cambridge University Press, Cambridge, U.K: chap. III.4, 125-132.

Nash L.T., Bearder S.K., Olson T.R. (1989). Synopsis of Galago species characteristics. Int J. Primatol.: 10, 57-80.

Nash L.T., Harcourt C.S. (1986). Social organization of galagos in Kenyan coastal forests: 2 Galago garnetti. Amer. J. Primatol.: 10, 357-369.

Oates J.F. (1996). African Primates Status Survey and Conservation Action plan. IUCN/SSC Primate Specialist Group.

Wilson D.E., Reeder D.M. (Eds) (1993). Mammal Species of the World: A Taxonomic and Geographic Reference. Second edition. Smithsonian Institution Press, Washington D.C.