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Macroscelidea
Id code: amd244Macroscelididae
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 (km
2) 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.