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Artiodactyla Id code: amd169

Bovidae

Gazella soemmerringii

(Cretzschmar, 1826)

(Eng) Soemmerring's gazelle

(Fre) Gazelle de Soemmering

Taxonomic notes

Up to six races have been described and three recognised (Spinage, 1986; Kingdon, 1997).

IUCN threat category

Vulnerable (VU: criteria C1).

Available information

Literature available on the species is scarce, and information on its ecology very poor. A description of its habitat, diet, and habits, is found in Estes (1991), Funaioli (1971), Kingdon (1997), and Stuart & Stuart (1997). Some notes on its ecology, mainly on its habitat, are also found in Spinage (1986) and Yalden et al. (1996). Status and distribution are discussed in East (1988); the author also gives some information on its ecology, particularly its habitat requirements.

Known extent of occurrence

The Soemmerring’s gazelle is an East Africa endemic, present only in Djibouti, Eritrea, Ethiopia, Somalia, east-central Sudan (Wilson & Reeder, 1993) and possibly as far south as extreme north Kenya (East, 1996). The distribution map was obtained from Kingdon (1971-1977) and updated according to country maps in East (1988) (Fig. 8.6.18.a). According to Dr. R. East (23 June '97) this species might be considered nearly extinct in Sudan.

Categorical-discrete (CD) distribution model

The species favours rough, hilly country with scattered evergreen thickets and Acacia/Commiphora steppe, as well as, open, short grass plains (Kingdon, 1997; East 1988; Spinage, 1986).

Based on these environmental preferences, the following scores were assigned (Fig. 8.6.18.b) (8.6.18.a):

Score

 

1

Grasslands, bushlands, thickets and their mosaics; semi-desert vegetation.

2

Woodland mosaics.

3

Desert, forests, woodlands and croplands.

suitable

moderately suitable

unsuitable

Total

km2

%

km2

%

km2

%

km2

%

595 795

55

104 977

10

384 577

35

1 085 349

100

Tab 8.6.18.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

257

2 320

19 427

38.34

1.32

5.73

moderately suitable

382

277

3 504

9.75

1.24

9.31

Total AO

256

2 742

21 429

38.96

1.3

6.14

Tab 8.6.18.b: Area of Occupancy fragmentation indexes.

Probabilistic-continuous (PC) distribution model

The output of the probabilistic-continuous (PC) distribution model is shown in Fig. 8.6.18.c.

Validation

No occurrence of the species within the four sample areas.

Comments and conservation issues

A broken and discontinuous EO of which only 65% is classified as AO. The areas of poorest quality appear to be mostly in Sudan and central Ethiopia. The known EO is certainly redundant, as for most gazelles which are now heavily hunted and exterminated in a large part of their AO. The fragmentation of the EO is further increased by the fragmentation of the AO, as shown by the indexes. In theory, about 10% of the total AO is included in the existing protected areas, but these are mostly distributed in Ethiopia, while the rest of the AO is not covered. The species is classified as Vulnerable, but the spatial patterns may require its status to be shifted to a higher threat category.

SUITABILITY CLASS

inside

outside

Total

suitable

5.15

49.74

54.89

moderately suitable

0.80

8.87

9.67

unsuitable

2.46

32.98

35.43

Total

8.42

91.58

100

Tab 8.6.18.c: Percent of environmental suitability classes within EO (as obtained from the categorical-discrete distribution model) inside and outside the protected areas.

References

East R. (Ed.) (1988). Antelope Global Survey and Regional Action plans, Part I: East and North East Africa. IUCN/SSC Antelope Specialist Group.

East R. (Ed.) (1996). Antelope survey update. IUCN/SSC Antelope Specialist Group: n° 2.

Estes R.D. (1991). The Behavior Guide to African Mammals. Including Hoofed Mammals, Carnivores, Primates. The University of California Press.

Funaioli U. (1971). Guida breve dei mammiferi della Somalia. Istituto Agronomico per l'Oltremare. Biblioteca Agraria Tropicale.

Kingdon J. (1971-77). East African Mammals. VOL I: primates, hyraces, pangolins, protoungulates, sirenians. VOL IIA: Insectivores and bats. VOL IIB: hares and rodents. VOL IIIA: carnivores. VOL IIIB: large mammals. VOL IIIC: bovids. VOL IIID: bovids. Academic Press, London and New York.

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

Spinage C.A. (1986). The Natural History of Antelopes. Croom Helm Publishers Ltd, London. Mamm. Series.

Stuart C., Stuart T. (1997). Field guide to the larger mammals of Africa. Struik Publishers.

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.

Yalden D.W., Largen M.J., Kock D., Hillman J.C. (1996). Catalogue of the mammals of Ethiopia and Eritrea. 7. Revised checklist, zoogeography and conservation. Tropical Zoology: 9, 73-164.