Feasibility of Local, Small-Scale Commercial Native Plant Harvests for Indigenous Communities
– Sustainable Use of Cycads in Central and Eastern Arnhem Land, Northern Territory, Australia
Key Centre for Tropical Wildlife Management
Northern Territory University,
Darwin, NT 0909 Australia
1. Banygul (1) Yunupingu, Laklak Yunipingu-Marika, Dhuwarrarr Marika, Banuk Marika, Balngayngu Marika, Raymattja Marika and Glenn, Wightman, 1995. Rirratjingu Ethnobotany: Aboriginal plant use from Yirrkala, Arnhem Land, Australia. Northern Territory Botanical Bulletin No. 21, Parks and Wildlife Commission of the Northern Territory, Darwin
2. Burbridge, A.H. and Whelan, R.J., 1982. Seed dispersal in a cycad, Macrozamia riedlei. In *Australian Journal of Ecology,*vol. 7, pp. 63-67.
3. Clark, D.A and Clark, D. B., 1987. Temporal and environmental patterns of reproduction in Zamia skinneri, a tropical rainforest cycad. In Journal of Ecology, vol. 75, pp.135-149.
4. Degener, O., 1949. Naturalist’s South Pacific Expedition: Fiji. Honolulu pp. 303.
5. Harvey, A., 1945. Food preservation in Australian tribes. Mankind, vol. 3, pp.191-192
6. Hill, K.D. & Stevenson, D.W. 1998. The Cycad Pages. http://plantnet.rbgsyd.gov.au/PlantNet/cycad/
7. Ornduff, R., 1989. Size distribution and coning behaviour of the Australian cycad *Lepidozamia peroffskyana.*In Australian Journal of Ecology, vol. 14, pp. 241-245.
8. Stevenson, D.W., 1992. A formal classification of the extant cycads. Brittonia, vol. 44. pp.220-223.
9. Whiting, M.G., 1963. Toxicity of cycads. Economic Botany, vol.17, pp.271-302.
Cycads are tropical or subtropical plants. Typically, individual genera have a restricted geographic range. They belong to the Family Cycadaceae of the Gymnospermae and there are 250 species in 11 genera (Hill and Stevenson, 1998). The genera include:Bowenia, Ceratozamia, Cycas, Chigua, Dioon, Encephalartos, Microcycas, Macrozamia, Stangeria, Lepidozamia, and Zamia (Stevenson, 1992). The Cycadaceae dominated over other vegetation during the greatest part of the Mesozoic period (Whiting, 1963) and are known to have lived as far back as the Permian era, over 200 million years ago (Hill and Stevenson, 1998).
Cycads are dioecious (ie. male and female cones are borne on separate plants), and all living cycads have cones of two kinds: pollen bearing and seed bearing. The cones, which are produced on separate plants on modified leaves called sporophylls, are arranged at the top of the stem either as loose whorls or in compact aggregations. Seeds have an outer fleshy layer and an inner stony portion, the two portions being separated by a paper-thin membrane (Whiting, 1963).
Cycads are slow growing and have two slightly different growth forms, one a tuberous form and the other showing a columnar-like stem. The tuberous stems are either short or subterranean and are often branched. The columnar types may reach a height of 30 feet or more and are seldom branched. Although cycads are considered woody plants, their stems have only a thin layer of wood, which surrounds a large pith or marrow and is enclosed by a heavy cortex.
Significance to Indigenous Peoples
Plants in this family often have significant nutritional value in the form of edible starches which can be extracted from the root, stem and nuts. The presence of toxic compounds in various tissues have long been recognised by a variety of indigenous peoples and precautions are accordingly taken in preparation. The Aboriginal people in eastern Arnhem Land collect the seed of Cycas orientis, which is endemic in this area, sun dry them for 2 days, chip them into small pieces, place them in running water for five days and then pound the result into a coarse paste used to make dampers or bread(Yunupingu et al., 1995).
Various indigenous cultures consider that certain cycads possess medicinal values. Cycads are also culturally significant in other ways. On the Melville Island, the cycad is among the plants selected for important ceremonies (Whiting, 1963) and in the Borroloola district the Karawa people use the cycad in initiation and other ritual ceremonies (Harvey, 1945). In Fiji, cycad fruits are reserved for chiefs (Degener, 1949).
Cycads are used as food, ceremonial or medicinal purposes in Guam, Australia, India, Indonesia, Africa, Java, Columbia, Mexico, and Florida (Whiting, 1963).
Probably due to their aesthetical appeal, members of the Family Cycadacea are collected by enthusiasts the world over. Many species have geographically restricted distributions and some are considered endangered or threatened, due primarily to unlawful extraction by poachers.
Extraction of Cycads from Arnhem Land
Cycas arnhemica andC. orientis occur in populations on Aboriginal land in central and eastern Arnhem Land respectively. There are no cultural objections to the extraction of small numbers of cycads from these areas, as an element of the development of a small business enterprise for Aboriginal communities. Both the Parks and Wildlife Commission of the Northern Territory and the Federal Government have approved exports of small numbers of stems to meet overseas demand from collectors. It is thought that these species will be of considerable interest because: (i) they are only found in Arnhem Land, Australia; (ii) they will be harvested by Aboriginal traditional owners; and (iii) incomes be retained by the Aboriginal communities. Although the number of stems proposed for export is trivial in the context of total population sizes, conditions of export under the relevant species management plan include close monitoring of environmental impacts. Sufficient data has been collected on some species to permit modelling of population dynamics to simulate the effects of harvest.
Harvest of cycad stems appears to be economically feasible, culturally appropriate and, at the levels permitted under very stringent management plans, ecologically sustainable.
Trial harvests are set to commence in central and eastern Arnhem Land in the dry season of 2001. The aims of these harvests and associated scientific work will be to:
- determine growth and survival of plants harvested from the wild for commercial sale;
- test market interest;
- examine the economies of collection, maintenance and export;
- use the experimental harvests to gather additional data on population dynamics.
Should these trials indicate the export is feasible and demand is likely to be substantial and maintained, then full population models will be developed to permit calculation of larger sustainable harvests. However, any expansion of the trade will be subject to independent examination by Northern Territory and Federal conservation authorities. All actions taken will be entirely consistent with the Convention on International Trade in Endangered Species of Flora and Fauna (CITES) and the Australian impending legislation, which is considerable more stringent than the Convention.
A PhD project titled,'Demography of cycads and implications for harvest', is being conducted by Mr Dave Liddle in conjunction with the Key Centre and Parks and Wildlife Commission of the Northern Territory.