
Cycad
Encephalartos whitelockiiP.J.H.Hurter
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Pays · région · aire protégée · écorégion · biome
Graphe en cours d’indexation
Calcul du tissu écologique de Encephalartos whitelockii.
Le graphe apparaîtra automatiquement dès que le calcul est terminé (rafraîchissement toutes les 5s).
Liste rouge IUCN
CR · En danger critiquecritères B1ab(iii,v)+2ab(iii,v)↘Décroissante- Évaluation
- 2024 · v3.1
- Altitude
- 1000 – 1200 m
- Profondeur
- – m
État de la populationTexte officiel évaluation IUCNExpert
The population size of Encephalartos whitelockii is estimated to be 8,000 mature individuals. Seedlings and small plants are absent from open habitats which may be as a result of too frequent fires, but under forest canopy, prolific regeneration occurs. The recorded sex ratio is 43% female to 57% male. The population has declined since 2008 initially due to the construction of a hydroelectric plant but also due to land invasions and clearing for cash crops.
Menaces identifiées(7 menaces classées CMP-IUCN)
2_1_2Small-holder farmingRapid DeclinesMinority (<50%)Ongoing4_1Roads & railroadsNegligible declinesMinority (<50%)Ongoing3_3Renewable energySlow, Significant DeclinesMinority (<50%)Ongoing2_3_2Small-holder grazing, ranching or farmingOngoing5_2_1Intentional use (species is the target)Ongoing5_3_1Intentional use: (subsistence/small scale) [harvest]Ongoing7_1_1Increase in fire frequency/intensityOngoing
Description complète des menacesTexte détaillé évaluation IUCNExpert
Threats to the species include:
a) Construction of a small hydro electric power plant on the Mpanga River Falls:
i - construction of roads and camps in the cycad belt, causing soil erosion and deep gullys, reducing habitat quality
ii - reduction in population of mature and young individuals as they are knocked down by heavy machinery
iii - reduction in area of habitat owing to parts being occupied by weir (reservoir), water canal, and power house
It was reported that the actual area of cycads impacted by the construction is probably less than 5% of the total area inhabited by the cycads. (Luke and Luke 2010)
b) Local community activities:
i - reports of collection of seed and seedlings for commercial trade may impair the regeneration capacity of the cycad and thus lead to further reduction of its population
ii - cultivation on the slopes of the gorge and clearing of land for cash crops
iii - harvesting of the cycad leaves for building materials
iv - burning of some areas occupied by the cycad for stimulation of grazing pasture.
a) Construction of a small hydro electric power plant on the Mpanga River Falls:
i - construction of roads and camps in the cycad belt, causing soil erosion and deep gullys, reducing habitat quality
ii - reduction in population of mature and young individuals as they are knocked down by heavy machinery
iii - reduction in area of habitat owing to parts being occupied by weir (reservoir), water canal, and power house
It was reported that the actual area of cycads impacted by the construction is probably less than 5% of the total area inhabited by the cycads. (Luke and Luke 2010)
b) Local community activities:
i - reports of collection of seed and seedlings for commercial trade may impair the regeneration capacity of the cycad and thus lead to further reduction of its population
ii - cultivation on the slopes of the gorge and clearing of land for cash crops
iii - harvesting of the cycad leaves for building materials
iv - burning of some areas occupied by the cycad for stimulation of grazing pasture.
Habitats préférentiels (classification IUCN)
1_6Forest - Subtropical/Tropical Moist Lowland2_1Savanna - Dry6Rocky areas (eg. inland cliffs, mountain peaks)
Mesures de conservation recommandéesStratégies de conservation IUCNExpert
This species is listed in Appendix I of the CITES Appendices. Only a very small part of the gorge falls within the Queen Elizabeth National Park, thus no more than 2% of the population occurs inside the park. Community sensitization has been done in the area but harmful community activities such as burning and cutting continue. Identification of further suitable sites for the formal protection of this species is needed. Long-term monitoring of the population will support the conservation of this species.
Actions de conservation (2)Conservation Actions Classification Scheme — IUCNExpert
1_1Site/area protection4_3Awareness & communications
Stress écologiques (13)Stresses Classification — IUCNExpert
1_1Ecosystem conversion1_1Ecosystem conversion1_2Ecosystem degradation1_2Ecosystem degradation1_2Ecosystem degradation1_2Ecosystem degradation2_1Species mortality2_1Species mortality2_1Species mortality2_1Species mortality2_2Species disturbance2_3_6Skewed sex ratios2_3_8Other
Usage & commerce (2)Use & Trade — IUCNExpert
13Pets/display animals, horticultureinternationalnational9Construction or structural materialssubsistance
Priorités de recherche (4)Research Needed Classification — IUCNExpert
1_2Population size, distribution & trends1_3Life history & ecology1_6Actions3_1Population trends
Niche IUCN globaleRealms · Systems · LMEs · Growth forms · FAOs — biogéographie IUCNExpert
Royaumes biogéographiques
Afrotropical
Systèmes (terrestre/eau douce/marin)
Terrestrial
Formes de croissance
CycadTree - large
Références bibliographiques (8)Sources scientifiques de l'évaluation IUCNExpert
- IUCN. 2024. The IUCN Red List of Threatened Species. Version 2024-1. Available at: <a href="www.iucnredlist.org">www.iucnredlist.org</a>. (Accessed: 27 June 2024).
- Luke, Q. and Luke, T. 2010. Site Visit Report: Mpanga River Gorge, Uganda 21st and 22nd August 2010.
- Byaruhanga, A., Kalema, J. and Namara, A. 2008. The Impact of Dam Construction on the Biodiversity and Ecology of Mpanga River Gorge, Kamwenge District, Western Uganda.
- Whitelock, L.M. 2002. <i>The Cycads</i>. Timber Press, Portland, Oregon.
- Hurter, J. and Claassen, I. 1996. Focus on <i>Encephalartos whitelockii</i>. <i>Encephalartos</i> 48: 4-9.
- Donaldson, J.S. 1995. Understanding cycad life histories- an essential basis for conservation. In: Donaldson, J.S. (ed.), <i>Cycad Conservation in South Africa- Issues, actions and priorities</i>, pp. 8-13. Cycad Society of South Africa.
- Vorster, P. and Heibloem, P. 1995. <i>Encephalartos successibus</i> (Zamiaceae): a new species from Uganda. <i>South African Journal of Botany</i> 61(6): 347-351.
- Hurter, P.J.H. 1995. Two newly described cycads from Africa. <i>Phytologia</i> 78(6): 409-416.
Évaluateurs & contributeurs (3)Personnes ayant contribué à l'évaluation IUCNExpert
assessor
Bösenberg, J.D.
contributor
Kalema, J.
evaluator
Donaldson, J.S.
Bösenberg, J.D. 2024. Encephalartos whitelockii. The IUCN Red List of Threatened Species 2024: e.T41928A51045938. Accessed on 05 May 2026.
Distribution mondiale
Calcul de la distribution GBIF· ~10–60 s
Phénologie
Calcul du calendrier d'apparition· ~5–30 s
Consulter sur les bases externes
Observations & statuts
Cartographie
Note nomenclaturale & synonymesDétails taxonomiques + synonymes CoLExpert
Note nomenclaturale
TAXREF v18 — INPN/MNHNSynonymes (2)— redirigent vers cette page
- Encephalartos successibusVorster
- Encephalartos successivusVorster
Sources : Catalogue of Life Cross-References (synonymes) · TAXREF v18 INPN/MNHN (commentaires FR).