Mustela itatsi 


Taxonomy [top]

Kingdom Phylum Class Order Family
Animalia Chordata Mammalia Carnivora Mustelidae

Scientific Name: Mustela itatsi
Species Authority: Temminck, 1844
Common Name(s):
English Japanese Weasel
Mustela sibirica subspecies itatsi Temminck, 1844
Taxonomic Notes: Abramov (2000), Kuroseet al. (2000), and Graphodatsky et al. (1976) supported separation of itatsi from sibirica. It is sometimes considered a subspecies of the Siberian Weasel Mustela sibirica.

Assessment Information [top]

Red List Category & Criteria: Least Concern ver 3.1
Year Published: 2008
Date Assessed: 2008-06-30
Assessor(s): Abramov, A. & Wozencraft, C.
Reviewer(s): Duckworth, J.W. (Small Carnivore Red List Authority) & Schipper, J. (Global Mammal Assessment Team)
This species is listed as Least Concern, although there is interspecific competition with introduced populations of Mustela sibirica this species is widespread geographically in Japan and is not thought to be declining at a rate to qualify for a threat category.
Previously published Red List assessments:
2003 Not Evaluated (NE)

Geographic Range [top]

Range Description: This species is endemic to Japan on Honshu, Kyushu, Shikoku, Sado, Oki Islands, Izu-Oshima, Awaji, Shoudo, Iki, Goto Islands, Yaku and Tane, and introduced to Hokkaido in the 1880s (Inukai 1934). It was introduced for control of rats on about 50 islands, including Sakhlain, Rishiri, Rebun, Izu Islands (Miyake, Hachijo, Aogashima), Aoshima (Nagasaki Prefecture), Kuchino, Nakano, Suwanose, Hira, Akuseki, Kikai, Okinoerabu, Yoron (Kagoshima Prefecture), Zamami, Aka, Minami-Daito, Kita-Daito, Irabu, Iriomote, Hateruma (Okinawa Prefecture) (Shiraishi 1982). It is naturalized on some islands (Abe, 2005). It is found in most elevation zones, but mainly at lower elevations (Sasaki pers. comm. 2006).
Countries occurrence:
Range Map: Click here to open the map viewer and explore range.

Population [top]

Population: This species is common.
Current Population Trend: Decreasing
Additional data:
Population severely fragmented: No

Habitat and Ecology [top]

Habitat and Ecology: This species occurs in grasslands, forests, villages, and suburbs, but not in big cities (Sasaki pers. comm. 2006). Rodents, insects, amphibians and reptiles make up the main part of its diet (Sasaki pers. comm. 2006). It shows extreme sexual dimorphism (male:450 g, female:150 g ) (Sasaki pers. comm. 2006). It is found in most habitats across Japan.
Systems: Terrestrial

Threats [top]

Major Threat(s): It does not tolerate urbanization (Sasaki pers. comm. 2006). In western Japan, the Japanese Weasel is being driven to marginal montane habitats by competition with the introduced Siberian Weasel (Mustela sibirica) (Abe, 2005).

Conservation Actions [top]

Conservation Actions: Females of this species are protected from hunting by law (Sasaki pers. comm. 2006). It is ranked as a near threatened species in the Red List of nine prefectures in the western Japan (Sasaki pers. comm. 2006).

Classifications [top]

1. Forest -> 1.4. Forest - Temperate
suitability: Suitable  
3. Shrubland -> 3.4. Shrubland - Temperate
suitability: Suitable  
4. Grassland -> 4.4. Grassland - Temperate
suitability: Suitable  
14. Artificial/Terrestrial -> 14.1. Artificial/Terrestrial - Arable Land
suitability: Marginal  
14. Artificial/Terrestrial -> 14.2. Artificial/Terrestrial - Pastureland
suitability: Marginal  
14. Artificial/Terrestrial -> 14.3. Artificial/Terrestrial - Plantations
suitability: Marginal  

In-Place Research, Monitoring and Planning
In-Place Land/Water Protection and Management
  Occur in at least one PA:Yes
In-Place Species Management
In-Place Education
1. Residential & commercial development -> 1.1. Housing & urban areas
♦ timing: Ongoing    
→ Stresses
  • 1. Ecosystem stresses -> 1.1. Ecosystem conversion
  • 1. Ecosystem stresses -> 1.2. Ecosystem degradation

8. Invasive & other problematic species & genes -> 8.1. Invasive non-native/alien species -> 8.1.2. Named species (Mustela sibirica)
♦ timing: Ongoing    
→ Stresses
  • 2. Species Stresses -> 2.3. Indirect species effects -> 2.3.2. Competition

1. Research -> 1.1. Taxonomy
1. Research -> 1.2. Population size, distribution & trends
1. Research -> 1.3. Life history & ecology
3. Monitoring -> 3.1. Population trends

Bibliography [top]

Abe, H., Ishii, N., Ito, T., Kaneko, Y., Maeda, K., Miura, S. and Yoneda, M. 2005. A Guide to the Mammals of Japan. Tokai University Press, Kanagawa, Japan.

Inukai, T. 1934. The invasion and use of weasels in Hokkaido, Shokubutu oyobi Doubutu. 2(3): 1309-1317.

Shiraishi, S. 1982. Rat control by weasels. Saisyu to Shiiku 44(9): 414-419.

Wozencraft, W.C. 2005. Order Carnivora. In: D.E. Wilson and D.M. Reeder (eds), Mammal Species of the World: A Taxonomic and Geographic Reference. Third Edition, pp. 532-628. Smithsonian Institution Press, Washington, DC, USA.

Citation: Abramov, A. & Wozencraft, C. 2008. Mustela itatsi. The IUCN Red List of Threatened Species 2008: e.T41656A10530315. . Downloaded on 28 June 2016.
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