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Macroscelidea Id code: amd244

Macroscelididae

Rhynchocyon petersi

Bocage, 1880

(Eng) Black-and-rufous elephant-shrew

(Fre) Rat à trompe de Peters

Taxonomic notes

Two subspecies are currently recognised: R. p. petersi (mainland population) and R. p. adersi (islands stock) (Nicoll & Rathbun, 1990).

IUCN threat category

Endangered (EN: criteria B1+2c).

Available information

Almost nothing is known on the ecology of the species. Some information is found in Kingdon (1997). Status and distribution are discussed in Nicoll & Rathbun (1990); the authors also report on the habitat in which the species is found.

Known extent of occurrence

The black-and-rufous elephant-shrew is endemic to the eastern African coastal zone, being present only in south-east Kenya and east Tanzania, including the islands of Zanzibar and Mafia (Wilson & Reeder, 1993; Nicoll & Rathbun, 1990). Its distribution map (Fig. 12.1.15.a) was obtained from Kingdon (1971-77).

Categorical-discrete (CD) distribution model

This species inhabits coastal forest, montane forest and dense woodlands (Nicoll & Rathbun, 1990; Kingdon, 1971-77).

Based on these environmental preferences, the following scores were assigned (Fig. 12.1.15.b) (12.1.15.a):

Score

 

1

Forests and dense woodlands.

2

Forest mosaics; open woodlands, woodland mosaics and thickets.

3

Grasslands, shrublands and croplands.

 

suitable

moderately suitable

unsuitable

Total

km2

%

km2

%

km2

%

km2

%

2 743

4

42 999

60

26 065

36

71 807

100

Tab 12.1.15.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

47

57

58

0.6

1.18

1.47

moderately suitable

32

1 352

7 064

88.52

1.38

7.37

Total AO

34

1 351

7 459

96.19

1.35

7.68

Tab 12.1.15.b: Area of Occupancy fragmentation indexes.

Probabilistic-continuous (PC) distribution model

The output of the probabilistic-continuous (PC) distribution model is shown in Fig. 12.1.15.c.

Validation

No occurrence of the species within the four sample areas.

Comments and conservation issues

The EO is restricted to a very small range where the suitable areas account for only 4% of the total (2 743 km2) and the moderately suitable areas (69%) are the more important portion of the EO. The fragmentation of the AO is not very high as shown by the LPI (96.19%) but the unsuitable areas open wide void areas in the AO. Due to its small size and the threats to its habitat (forest destruction), this population is classified as Endangered; about 8.3% (3 800 km2) of the total AO is protected by parks or reserve, a small size to ensure the conservation of the species.

SUITABILITY CLASS

inside

outside

Total

suitable

0.08

3.74

3.82

moderately suitable

5.24

54.64

59.88

unsuitable

1.30

35

36.30

Total

6.62

93.38

100

Tab 12.1.15.c: Percent of environmental suitability classes within EO (as obtained from the categorical-discrete distribution model) inside and outside the protected areas.

References

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.

Nicoll M.E., Rathbun G.B. (Eds) (1990). African Insectivora and Elephant-Shrews. An Action Plan for their Conservation. IUCN/SSC Insectivore, Tree-Shrew and Elephant Shrew 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.