Encephalartos horridus

Assessor: Sarah Schumann

Sensitive in 2010
No
Family
Zamiaceae
Reason for the sensitivity status
This taxon is sensitive as it is threatened with illegal collection of wild individuals, causing population decline and reproductive failure in parts of its geographic range. Evidence shows that the Encephalartos genus is in high demand in international trade for ornamental and horticultural purposes as well as local medicinal purposes. The species has a small and declining population size remaining, making it vulnerable to further population loss and a poor chance of recovery from exploitation. Releasing data on this species can exacerbate threat and vulnerability.
This species is threatened by widespread, unregulated, unsustainable exploitation of wild populations. The localities of remaining populations need to be protected to avoid any further exploitation, which is likely to drive it to extinction.
Exploitation extent
Significant - wild individuals of the species are known to be exploited, collected, traded or utilized in a targeted manner, and utilisation is widespread, affects the majority of wild populations and/or is causing rapid decline of the wild population.
Justification and references

All South African cycads as well as this species is included in Appendix I of the CITES Convention which lists all species threatened with extinction that are, or may be affected by trade. According to the SANBI Red List Assessment, this species is Endangered as it is threatened by over-collecting for ornamental purposes and habitat loss, with a declining population trend (Donaldson 2009; Donaldson 2003). The species is now extinct in some areas of its historic geographical range (Donaldson 2009). Population numbers have decreased by 50% in the past 50 years due to over-collecting and urban development. Cycad species are in trade demand and at risk from illegal collection (Smith 2014; Yeld 2014). Studies present strong evidence of ongoing and accelerating rates of decline in most cycad species due mainly to illegal removal and this is especially evident with endangered and critically endangered Encephalartos species (Okubamichael et al. 2016; Cousins & Witkowski 2017). In 2016, 50% of one subpopulation was removed and 100% of another was removed (Okubamichael et al. 2016). Research suggests that this species is declining faster than the IUCN Red List suggests and needs to be re-assessed (Okubamichael et al. 2016). The CITES Trade Database has recorded the trade of the species from 1979-2019 for commercial, personal, scientific, educational, travelling exhibition and botanical garden purposes. Sourced from artificial propagation, and confiscated or seized. 

CITES trade statistics derived from the CITES Trade Database, UNEP World Conservation Monitoring Centre, Cambridge, UK.

Cousins, S.R. and Witkowski, E.T.F., 2017. African cycad ecology, ethnobotany and conservation: a synthesis. The Botanical Review83(2), pp.152-194.

Donaldson, J.S. 2003. Cycads. Status survey and conservation action plan. IUCN/SSC Cycad Specialist Group, Gland, Switzerland; Cambridge, UK.

Donaldson, J.S. 2009. Encephalartos horridus (Jacq.) Lehm. National Assessment: Red List of South African Plants version 2020.1. 

Okubamichael, D. Y., S. L. Jack, J. D. Bösenberg, M. T. Hoffman & J. S. Donaldson. 2016. Repeat photography confirms alarming decline in south African cycads. Biodiversity Conservation 25(11): 2153–2170.

Smith, D. 2014. 1 September 2014. South Africa's ancient cycad plants under threat from poachers. The Guardian. Available at: https://www.theguardian.com/world/2014/sep/01/ancient-cycad-plants-under-threat-poachers

Yeld, J. 2014. 7 August 2014. Cycad thieves strike again. IOL. Available at: https://www.iol.co.za/news/cycad-thieves-strike-again-1731799

Population vulnerability
Population is not vulnerable: size is > 2500 mature individuals, AND the number of known subpopulations is > 5 AND range > 100km2
Justification and references

According to the IUCN Red List, there are between 3000-7000 mature individuals remaining in the wild (Donaldson 2010). There are more than 5 subpopulations remaining (Donaldson 2009).

Donaldson, J.S. 2010. Encephalartos horridusThe IUCN Red List of Threatened Species 2010: e.T41905A10587904. https://dx.doi.org/10.2305/IUCN.UK.2010-3.RLTS.T41905A10587904.en

Donaldson, J.S. 2009. Encephalartos horridus (Jacq.) Lehm. National Assessment: Red List of South African Plants version 2020.1. 

Targeted demographics
Mature (breeding) individuals are killed, significantly weakened or are permanently removed from the wild, OR immature individuals are targeted and this significantly impacts mature (breeding) individuals.
Justification and references

Mature individuals are removed from the wild causing population decline (Donaldson 2009). The CITES Trade Database has recorded the trade of live individuals and seeds.

CITES trade statistics derived from the CITES Trade Database, UNEP World Conservation Monitoring Centre, Cambridge, UK.

Donaldson, J.S. 2009. Encephalartos horridus (Jacq.) Lehm. National Assessment: Red List of South African Plants version 2020.1. 

Regeneration potential
This species has a slow population growth rate, or the growth rate varies depending on habitat, and there is a poor chance the wild populations will recover from exploitation OR a collector might feasibly harvest the entire extant population removing the chance of subsequent recruitment.
Justification and references

Research shows that cycads are generally long-lived, have slow growth rates, produce low numbers of offspring and have infrequent recruitment (Golding & Hurter 2003, Donaldson 2003, Cousins & Witkowski 2017). Viable seed production in Encephalartos populations tends to decline with decreasing population size (Cousins & Witkowksi 2017). The removal of mature individuals results in reproductive failure and with a small population remaining as well as ongoing decline of populations in the wild, there is a poor chance of recovery from exploitation (Donaldson 2009). Smaller subpopulations are more likely to experience declines than larger subpopulations as a result of fragmentation processes (Golding & Hurter 2003).

Cousins, S.R. and Witkowski, E.T.F., 2017. African cycad ecology, ethnobotany and conservation: a synthesis. The Botanical Review83(2), pp.152-194.

Donaldson, J.S. 2003. Cycads. Status survey and conservation action plan. IUCN/SSC Cycad Specialist Group, Gland, Switzerland; Cambridge, UK.

Donaldson, J.S. 2009. Encephalartos horridus (Jacq.) Lehm. National Assessment: Red List of South African Plants version 2020.1. 

Golding, J.S. and Hurter, P.J.H., 2003. A Red List account of Africa's cycads and implications of considering life-history and threats. Biodiversity & Conservation12(3), pp.507-528.