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Bjorå et al. Journal of Ethnobiology and Ethnomedicine (2015) 11:82 DOI 10.1186/s13002-015-0060-0 JOURNAL OF ETHNOBIOLOGY AND ETHNOMEDICINE RESEARCH Open Access The uses of Kenyan aloes: an analysis of implications for names, distribution and conservation Charlotte S. Bjorå1* , Emily Wabuyele2,3, Olwen M. Grace4, Inger Nordal2 and Leonard E. Newton3 Abstract Background: The genus Aloe is renowned for its medicinal and cosmetic properties and long history of use. Sixty-three Aloe species occur in Kenya, of which around 50 % are endemic. Several species of aloes are threatened with extinction and knowledge about their use is of major importance for sound conservation strategies. The main aims of this study were to assess the biocultural value of Aloe in Kenya by documenting local uses of aloes and evaluating how the vernacular names reflect the relative importance in different ethnic groups. Methods: Ethnobotanical and ethnotaxonomical data were collected using field observations and semi-structured interviews. Information was collected by interviewing 63 respondents from nine different ethnic groups, representing different ages, gender and occupations. Statistical analyses were performed using R version 3.1.2. Results: A total of 19 species of Aloe were found in the study area, of which 16 were used. On the generic level Aloe was easily distinguished. At species level, the local and scientific delimitation were almost identical for frequently used taxa. Aloe secundiflora, with 57 unique use records was the most important species. The two most frequently mentioned Aloe treatments, were malaria and poultry diseases. In our study area neither age nor gender had a significant influence on the level of knowledge of Aloe use. Finally, no correlation was found between extent of use and people’sperception of decrease in local aloe populations. The aloes are highly appreciated and are therefore propagated and transported over large areas when people relocate. Conclusion: Biocultural value is reflected in the ethnotaxonomy of Aloe in Kenya. Different ethnic groups recognise their most-valued Aloe at the genus level as “the aloe” and add explanatory names for the other species, such as the “spotted aloe” and the “one-legged aloe”. Widespread species of Aloe have the highest number of uses. There is no obvious correlation with high use and decrease in abundance of aloes locally, and we found no compelling evidence for local uses causing devastating damage to populations of the 19 species in use, whereas habitat loss and commercial harvesting appear to be of urgent concern for these important plants. Keywords: Aloe, Ethnobotany, Ethnotaxonomy, Folk use, Conservation, Kenya, Plant use Background significance [7], i.e. Aloe vera, A. perryi Baker, A. ferox The genus Aloe L. is renowned for its medicinal and cos- Mill. and A. arborecens Mill. metic properties that have been exploited over millennia Kenya is known for its high diversity of aloes [8–11]. [1–4], including the popular species Aloe vera (L.) Carter et al. [8] reported 59 species in Kenya, and since Burm.f. which was recorded in use as early as 400 BCE then four more species have been described [12, 13]. Due [5]. The genus contains around 550 species [6] but only to their multi-use nature, Kenyan aloes have in been a few species feature in international trade of any harvested at household level over many years mainly for use as herbal remedies in combination with other plants [14]. The commercial exploitation of aloes in Kenya was * Correspondence: [email protected] 1Natural History Museum, University of Oslo, P.O. Box 1172, Blindern 0318 first reported in the 1960s, when substantial amounts of Oslo, Norway wild-harvested leaf extracts, mainly of A. secundiflora Full list of author information is available at the end of the article © 2015 Bjorå et al. Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. Bjorå et al. Journal of Ethnobiology and Ethnomedicine (2015) 11:82 Page 2 of 16 Engl., were exported to the USA [15]. Since then, several species. Plant value, in particular, can be a convincing similar incidents of wild harvested aloe extracts for sale argument for conservation attention, but is difficult to have been reported [16, 17]. In 1986, the then president of quantify since folk uses and cultural significance are rarely Kenya declared a ban on harvesting wild-growing aloes in evaluated in economic terms [7]. Grace et al. [4] argued recognition of the potentially devastating effects of har- that a variety of indicators can be used to estimate the cul- vesting on the plants and their habitats [18]. However, the tural and economic value of Aloe, such as the number of presidential decree was not translated into a legal instru- vernacular names and number of uses recorded for a ment and was largely ignored [16]. In some areas where species. Holman [25] demonstrated that the ways local the law was adhered to, it led to more harm than protec- communities name plants reveals important information tion [19]: rather than defoliating plants in natural popula- about the plants’ relative importance to the community. tions and allowing recovery, plants of Aloe secundiflora Earlier studies have shown that in South Africa most were dug up and re-planted in “plantations”.In2007 species of Aloe are used [26], and the same has been stakeholders consulted widely and came up with Aloe reported about aloes in Kenya [16]. In this study, we Utilization guidelines that were gazetted by the Kenya aimed to assess the contemporary biocultural importance government at the end of 2007 as subsidiary legislation of Aloe species in Kenya, using a case study to examine [20], bridging the legal gap in the aloe industry. the uses, vernacular names and sustainability of non- In Kenya today, the species A. secundiflora, A. turkanen- commercial wild harvesting and gather perceptions of sis Christian, A. rivae Baker, A. calidophila Reynolds, and population changes among nine ethnic groups in Kenya. A. scabrifolia L.E.Newton & Lavranos are reported to be Specifically, the aims of this study were to document the commercially exploited for aloe bitter exudate [17, 21]. A. vernacular names and local uses of aloes in Kenya, explore scabrifolia and A. turkanensis [16]areparticularlythreat- the distribution of local knowledge about Aloe species in ened by organized collecting activities coordinated by relation to age and gender, and record people’sunder- dealers, who have trained local communities in Aloe pro- standing of changes in abundance and distribution of cessing techniques, to supply illegal export of large quan- aloes. tities of dried exudate [21, 22]. This trade is sustained by the global demand for Aloe products [7]. Another, less Methods specific threat to the aloes is the general loss and destruc- Study area tion of habitats due to increase in human and livestock The study area (Fig. 1a) was selected to areas in Kenya populations (e.g. [23]). In addition to national protection with a minimum of two Aloe taxa present, and areas of in Kenya, aloes and their products are regulated in inter- very low human population density, like Northern Kenya, national trade by the Convention on International Trade were avoided. The study area was further selected to in- in Endangered Species (CITES) and are all listed on clude a wide range of ethnic groups, representing different CITES appendix II [9]. The IUCN Red List [24], further- linguistic groups: Cushitic, Nilotic and Bantu (Fig. 1b). more, records only seven species of Aloe in three most When this fieldwork was undertaken, Kenya comprised threatened categories ‘Critically endangered,’ ‘Endangered’ eight provinces (Swahilia: mikoa), that were subdivided or “Vulnerable”. The 25 endemic Aloe species of Kenya into 69 districts (wilaya) and 497 divisions (taarafa). were evaluated by Wabuyele et al. [11], who concluded Under the new constitution (envisioned by the 2010 that no fewer than 16 species were either ‘Critically en- Constitution of Kenya), the former subdivisions were dangered’ or ‘Endangered,’ according to IUCN Red List abandoned, and Kenya is now divided into 47 counties. criteria. In spite of growing awareness for the threats to Counties where information was collected are highlighted Aloe species in Kenya and these attempts to protect them, in grey (Fig. 1a), with the old provinces indicated. illegal harvesting is still taking place. Although there is The ethnobotanical survey was undertaken during evidence of an ongoing demand for the processed aloe August and September 2005. Information was collected exudate, the (legal) non-commercial uses of Aloe species by interviewing 63 respondents from nine ethnic groups in rural communities, and the sustainability of local Aloe (Kamba, Kikuyu, Kisii, Masaii, Mbeere, Taita, Tugen, harvesting, have not been recently assessed. Samburu, Somali). Informants were selected to represent a Kenya’s drylands support 28 % of the total human broad spectrum of the communities, ages, gender and population and occupy 80 % of the land area. Sustainable occupations, from herders to herbalists. The two youngest utilization of Aloe resources in the drylands has been informants were 18 years old, the oldest estimated her age advocated [17] as a step towards empowering the local to around 100 years; the age and gender of informants are communities for better livelihoods and, indirectly, bio- presented in Fig. 2. Semi-structured interviews were con- diversity conservation. Knowledge about the uses of ducted with each respondent while walking in Aloe localities aloes is crucial to help prioritise conservation and re- in the vicinity of the respondents’ homes.