Euphorbia Cap-saintmariensis

Import and Export

Delays and expense in obtaining permits has hindered legitimate export of artificially propagated plants.

Zimbabwe

Export

Inadequate enforcement of national legislation results in some illegal trade in rare plants.

However, the standard of reporting for plants is generally poor. Many countries, for example, report only to family or generic level for cacti and other succulent plants, and other countries do not report on the plant trade at all. Nevertheless, a significant body of data on the international succulent plant trade has been compiled since the Convention came into force.

Monitoring of the trade through review of licence applications and analysis of annual reports can provide an early warning system of trade on a scale likely to cause conservation problems. This happened, for example, with the import of CITES Appendix II Madagascan succulent species in the mid 1980s. One species, Pachypodium was imported in the tens of thousands from Madagascar to Germany in 1985 and 1986 for sale in general horticultural outlets. The plants were claimed to be artificially-propagated but subsequent investigation demonstrated that all were wild-collected. In the same way thousands of wild plants of the slow-growing species Euphorbia cap-saintmariensis, E. cylindrifolia, E. mora tii, and E. primulifolia were imported into Europe in the mid-1980s, together with large numbers of Didierea and Alluaudia in the Didieriaceae. Concern about the volumes of trade lead to the transfer of certain Madagascan succulents to Appendix I of CITES in 1989 and to the temporary imposition of stricter importer controls on all species by the EC.

Data from the CITES annual reports is held on computer at WCMC in a form which allows for various analyses to be carried out. Comparisons can for example

Box 2.1 CITES trade data for cacti

Cacti are the most heavily traded group of plants recorded in CITES trade statistics. The average total number of cacti recorded in annual trade is over 13 million. This is unlikely to represent the total world trade in cacti. One wholesale nursery in the Netherlands for example, produces over 18 million cacti annually, mainly for the European market In the USA total cactus production has been estimated at up to 50 million annually, with over 20 million produced in nurseries of Vista, California alone (Fuller 1987).

The countries with the highest levels of reported average annual trade in cacti are the Netherlands (over six million), Japan (over five million), Brazil (over one million), Korea, Canada, Spain, and Dominican Republic. The high volume of trade in plants in most of these countries is predominantly in artificially propagated cacti produced domestically and does not give rise to any concern. The export of cacti from Brazil is different in that both artificially propagated specimens of indigenous and non-indigenous species are traded together with wild-collected plants.

Brazil has several major nurseries in the south of the country which are thought to deal entirely in artificially propagated plants. One nursery exports around five million cacti annually to a wholesale firm in the Netherlands. The Brazilian trade in Cactaceae is, therefore, clearly under reported. Some Brazilian cacti are relatively difficult to propagate and are still sought after as wild specimens. Concern about levels of trade in wild-collected plants of Uebelmannia and Discocactus, together with some species of Melocactus, led to the transferral of these species to Appendix I of CITES in 1992. There is also the possibility that wild-collected plants of other genera such as Notocactus are being exported in small quantities from Brazil.

It is thought that there is substantial under-reporting of cactus exports from other South American countries, The annual average reported trade for Peru, for example, is only 1037 plants, 55% of which are reported to be artificially propagated. There is an internationally known cactus nursery within the country which has regularly exported wild-collected plants in contravention of CITES during the past ten years.

The average annual number of cacti reported to be exported by Mexico is around 50,000. Of these, less than one percent are reported to be propagated. As the export of wild-collected cacti from Mexico has theoretically been banned for the past 50 years and many of the horticulturally desirable species are threatened in the wild, this scale of trade is obviously of considerable concern.

The most heavily traded cactus genus is Mammillaria, one of the largest genera in the Cactaceae with around 150 valid species and many other names in horticultural use. The centre of distribution for Mammillaria is Mexico and many species are confined to small areas within the country. Although the genus is very commonly cultivated, it has been reported that wild populations are exploited to fill the commercial demand for large specimens. Worrying levels of trade have been recorded in species such as M. dixanthocentron which is slow growing in cultivation and Vulnerable in the wild, and M. guerreronis, which is uncommon in cultivation. Newly described Mammillaria species are particularly vulnerable to collection. Several new species are described each year in Europe, possibly as a result of illegal export of field-collected material. Publication of locality details with description of new species attracts collectors and puts the plants at risk.

Other heavily traded cacti genera include Gymnocalycium,Echinopsis, and Notocactus. Despite their horticultural importance these South American genera are poorly known in the wild and are in need of taxonomic fieldwork. The region of southern Bolivia and north Argentina has the greatest diversity of small globular cacti after Mexico and they are subject to quite a strong demand from collectors.

Source: Oldfield(199 1)

be made of the data on transactions reported by exporting and importing countries. Discrepancies highlight problems which may be worthy of further investigation.

At the request of the Parties, a comprehensive review of all CITES Appendix II trade data was undertaken in 1991, reviewing all trade data for the period 1983-1989. The results of this 'Significant Plant Trade Study' were presented at the Eighth meeting of the Conference of the Parties in 1992. Particular attention was paid to the Cactaceae and a summary of the results is presented in Box 2.1. As part of the same project, trade in the genus Aloe and its parts and derivatives, has been subject to review. This concluded that the data on levels of trade in Aloe parts and derivatives contained within CITES Annual Reports currently have limited value for conservation purposes. The only significant trade in parts and derivatives from wild populations reported to the CITES Secretariat is the trade in Aloe ferox from South Africa. This trade is large but appears to be sustainable and does not currently have a detrimental impact on this widespread species. CITES monitoring has benefits for long-term management of A. ferox. Other countries which export Aloe products derived from indigenous species should report the trade in detail. Importing countries should also record and report the trade.

The data on levels of trade in live Aloe plants recorded in CITES statistics for the period 1983-1989, show that the most heavily traded species are generally 'not threatened' in the wild and are commonly artificially propagated. Relatively small-scale trade in rarer species may however be a cause for concern. Collector demand is thought to focus on South African and Madagascan rarities. A number of Madagascan species are strong candidates for Appendix I listing.

Improvement in national reporting of trade in CITES -listed succulents is a priority in increasing the effectiveness of the Convention. A review of national reporting procedures for trade in CITES plants is being carried out by WCMC in response to a recommendation of the 'Significant Plant Trade Study'.

Regular review of the CITES trade data for succulents is essential in monitoring the application of the Convention to trade in these plants. A long-term goal should be to relate trade data to biological data and information on nursery production for each species of conservation concern in order to determine management policies for sustainable trade. At present there are major gaps in the available information most notably on the impact of commercial trade on succulent populations in the wild. Under the ongoing CITES Significant Plant Trade process, projects are now being implemented which relate levels of trade to the status of rare species in the wild. Recent projects carried out in Madagascar and Mexico are examples referred to in the regional accounts.

Illegal trade

There is no doubt that illegal trade in wild succulent plants continues in contravention of CITES (see Table

Mammillaria limonensis in cultivation at Can Te, A.C. gardens, Mexico.

2.5). Smuggling of small quantities of rare wild plants in suitcases or through the post, or mis-declaring of openly imported shipments are examples of the activities which continue and are extremely difficult to stop given the current level of resources. Surveys conducted by TRAFFIC in Europe, Japan, and South Africa in the past few years have revealed the widespread and often open availability of Appendix I listed wild plants in nurseries. The recent survey of European nurseries by TRAFFIC Europe revealed that wild plants of the Appendix I cacti Ariocarpus, Aztekium, Obregonia, Pelecyphora, and Strombocactus were all on sale in Italy. Austria has been a source of wild specimens of Ariocarpus on sale in Italy, but does not report in detail on its plant trade. Wild Ariocarpus plants have been sold openly in the Amsterdam flower market, and nurseries in Belgium and Germany continue to stock Appendix I rarities. Early in 1992 seventy cacti including Ariocarpus and Strombocactus were seized from a shop in Paris.

A clear-cut example of illegal international trade in rare cacti is provided by the commercial availability of the recently described species Aztekium hin tonii and Geohintonia mexicana. The original descriptions of the new taxa were published in the Mexican journal Cactaceas y Suculentas Mexicanas at the end of 1991. Other specialist journals publicised the discovery of these new cacti (Geohintonia is a new genus). The following year the new taxa were already present in commercial nurseries and private collections within Europe. All specimens outside Mexico are illegal both under Mexican national legislation and under CITES, as no export permits have been issued.

At the CITES Conference of the Parties, held in Kyoto in 1992, Mexico called on importing countries to help with problems of illegal plant exports. In 1991, 18 foreigners were caught illegally collecting cacti in Mexico; in some cases these were pseudo-conservationists "saving"

Jacob Bannon Art

Geohintonia mexicana wild plants. Recently, Mexican authorities have been studying where the collectors go to within the country and concentrating enforcement efforts in those areas.

Trade in non-CITES succulents

International trade in non-CITES succulents involves a wide range of species which frequently appear to be threatened in the wild and/or collected in contravention of national laws. This is the case, for example, with southern African succulents. A recent survey of German and Dutch succulent plant catalogues carried out for the German CITES Scientific Authority recorded the availability of threatened southern African succulents at 16 nurseries and noted indications of their wild status (Schippmann 1993). Although data on volumes of trade cannot be collected in this way, surveys of this kind can be a useful step in indicating species of potential concern.

In situ conservation

Sara Oldfield

Protecting wild plants in their natural habitats is generally considered to offer the best long term chance of survival for rare and threatened species. In situ protection can take various forms including legal protection of the habitat where the species occurs; designation of micro-reserves, nature reserves, national parks or other categories of protected area; land use controls or zoning restrictions; protection on private land; voluntary management agreements; habitat restoration; or the development of recovery plans for wild populations of threatened species. This section provides examples of different forms of in situ conservation for cacti and other succulents to supplement the information within the regional accounts.

Protecting the habitats of threatened species

Areas specifically protected for threatened species are relatively uncommon as most plant conservation legislation is concerned with protecting species from various forms of collection and disturbance. Habitat protection for threatened plants is, however, included in national conservation legislation for several European countries and also in the USA. The US Endangered Species Act gives protection to the 'critical habitats' of threatened species including various cacti and other succulents. Critical habitats are defined as areas which are essential to the conservation of the species concerned. These areas must be designated and their boundaries precisely described in the Federal Register. As of October 1987, of the 168 listed species of wild flora, there were 23 species for which critical habitats had been designated (Groombridge 1992).

Protection of the habitats of threatened plant species

Habitat for Euphorbia canariensis, Los Palmitos Valley, Gran Canaria.

is also enshrined in regional conservation legislation. In Europe, for example, the EC Habitats Directive addresses the conservation of both natural habitats and habitats of threatened species by the establishment of a European network of Special Areas of Conservation (SACs) which collectively form the Natura 2000 network. New sites, identified by member states, in conjunction with the EC, include areas of natural habitat type listed in Annex I of Directive, with certain habitats given special priority, and habitats of the threatened species listed in Annex II. Habitat types included in Annex I which may be important for succulent plant protection include Mediterranean and pre-steppe brush (low formations of Euphorbia close to cliffs), various categories of rocky slopes, and Mediterranean montane forests.

Criteria for the selection of sites both at a national level (Stage 1) and EC level (Stage 2) are given in Annex III of the Directive. The criteria for selection of sites for species include size, density, and isolation of the population in relation to the national total, condition of the site, and global importance. All identified national sites of Annex II species will be considered as sites of EC Importance. Protection of the habitats of those endemic succulents of the Canary Islands included in Annex II (see Table 2.3) will therefore be protected under the Directive, reinforcing the protected area system outlined in Box 2.2.

The Habitats Directive obliges Member States to establish conservation measures for SACs with appropriate management plans, and to avoid the deterioration and disturbance of the protected sites. Environmental Impact Assessments are required for any developments which may adversely affect SACS.

Protected areas

The more common form of in situ protection for succulent plants is inclusion within the boundaries of land set aside for general conservation purposes. A protected area is defined as:

An area of land and/or sea especially dedicated to the protection and maintenance of biological diversity, and of natural and associated cultural resources, and managed through legal or other effective means. (IUCN 1994a)

At a global level, a recent study of habitat protection carried out by WCMC indicates that overall 7.7 per cent of tropical regions are conserved within protected areas. Protected area coverage of different habitat types is uneven with wet and moist major habitats better represented in protected areas than dry major habitats. This probably reflects national and foreign policies to promote the conservation of tropical rain forests as well as the fact that drier habitats are more prone to agricultural conversion (Green et al. 1995). The lack of protection for drier areas may indicate that succulent plant diversity is not adequately protected in the tropics. Green et al. (1995) note particularly the restricted protection for lowland dry and arid habitat types in Central America, the Caribbean, and South America. The study also notes the need to carry out similar quantitative assessment of the representation of centres of species diversity, speciation, and endemism within protected areas.

For plants, the Centres of Plant Diversity (CPD) project coordinated by IUCN has identified some of the most important sites for species diversity and endemism worldwide. These are the global priority areas for conservation of plant biodiversity. Individual CPDs which are particularly noteworthy for succulent plant species are listed in Table 2.6, which also indicates the extent to which the sites are currently protected. It is apparent that many CPDs are not legally protected, or are only protected in part. A considerable proportion of those sites which are officially protected are not effectively managed (WWF and IUCN 1994).

International designations

At an international level various mechanisms exist to protect globally important ecosystems and the species occurring within them. One such mechanism is the Convention Concerning the Protection of the World Cultural and Natural Heritage (World Heritage Convention). This Convention provides for the designation of areas of "outstanding universal heritage" as World Heritage sites, with the principal aim of fostering international cooperation in safeguarding these important sites. Few World Heritage sites are important

Box 2.2 Protected areas in the Canary Islands

The Canary Islands have a number of protected areas which are important for succulent plant conservation. Examples of succulent species which are protected in situ are included in Annex 6. Major National Parks occur on Tenerife, La Palma, La Gomera, and Lanzarote. In contrast, Gran Canaria, the island which has experienced the greatest degree of habitat destruction and modification, had, until recently, a relatively poorly developed series of protected areas. In the late 1980s a comprehensive review of species and habitats was undertaken on Gran Canaria in order to select sites in need of protection. As a result of the review, PEPEN - A Special Plan for the Protection of the Natural Areas of Gran Canaria - was published in 1986.

The following year, the Regional Government passed an intermediate law putting most of the proposed areas of PEPEN in a schedule of protected areas. It is now the responsibility of the Dirección General de Medio-Ambiente to prepare management plans for these sites. Despite the progress in protecting the unique succulent plant flora of the Canary Islands, there are however, still significant gaps in the protected area coverage. Lowland plant communities are, for example, not adequately covered. A new National Park is currently proposed to protect a large sector of the Euphorbia communities and eroded volcanic landscapes of Gran Canaria.

Source: Synge 1991

Table 2.6 Centres of Plant Diversity - Conservation status of succulent rich sites

Site

Vegetation

Conservation status

Cal Madow, Somalia

Dry montane forest

Daalo Forest Reserve, no protection in practice.

Hobyo area, Somalia

Deciduous bushland, woodland, dunes

No protected areas, extremely vulnerable to overgrazing.

Ogaden, Somalia / Ethiopia / Kenya

Deciduous bushland, woodland

No protected areas.

Socotra, Yemen

Semi-desert, shrubland, thicket, grassland

No protection, but traditional practices have prevented serious exploitation.

Cape Floristic Region, South Africa

Fynbos, shrubland, montane

Reserves cover 19% of region but mainly in mountains.

Karoo-Namib Region, South Africa/Namibia

Succulent shrubland

National Park and a few other reserves covering about 2% of region.

Madagascar

Predominantly forests and thicket

Protected areas cover less than 2% of the island.

Canary Islands

Coastal vegetation, Euphorbia-rich vegetation, scrub, woodland, forest

Many protected areas with some notable gaps for succulent rich sites.

Pinar del Rio, Cuba

Seasonal forests, succulent and thorn scrub

National Park; lowlands at risk.

Cockpit Country, Jamaica

Subtropical forest, scrub thicket

No protected areas.

Tehuacan Valley, Mexico

Dry scrub, deciduous forest

Small botanic garden.

Edwards Plateau, Texas, USA

Forest, grassland, semi-desert scrub

Protected areas cover less than 0.5% .

California Floristic Province

Forests, woodlands, coastal scrub, grasslands

About 11 % of land protected, mostly montane, lowland habitats threatened.

Atacama Desert, Chile

Mixture of annual, short-lived perennial and woody scrub

Two protected areas cover 468 km2, many endemics need more extensive protection.

Lomas, Peru/Chile

Islands of low montane desert scrub and thorny steppe

Lachay Nature Reserve, protected area coverage inadequate.

for succulent plant conservation. Exceptions are the Reserve naturelle intégrale du Tsingy de Bemaraha in Madagascar inscribed as a World Heritage site in 1990, the Grand Canyon National Park in Arizona, USA, and the Galapagos Islands.

Biosphere reserves are created under the UNESCO Man and the Biosphere (MAB) Programme. The objective of this Programme is to develop a scientific basis linking the natural and social sciences for the rational use of and conservation of the biosphere and for the improvement of the relationship between humans and their environment. Biosphere reserves are multipurpose areas dedicated both to the conservation of characteristic ecosystems and species, and to sustainable development to meet human needs. Currently the international network consists of over 285 biosphere reserves.

Various biosphere reserves are particularly important for succulent plant conservation. Mexico has six internationally recognised biosphere reserves including the Pinacate Biosphere Reserve covering 480,000 ha of the Sonoran Desert and adjoining the Organ Pipe National Monument in the USA (see below). The Mapimi Biosphere Reserve, established in 1977, covers over 100,000 ha of Chihuahuan Desert with more than 20 species of cacti (Box 2.3).

In the USA, an area of succulent plant diversity is protected in the Big Bend National Park, which is one of 47 biosphere reserves in the country. This National Park protects a large area of Chihuahuan Desert in Brewster County, Texas. Rare cacti occurring within Big Bend include Ancistrocactus tobuschii, Coryphantha ramillosa, Epithelantha micromeris var. bokei, and Sclerocactus mariposensis.

Box 2.3 Reserva de la Biosfera de Mapimi, México

Location Situated north-east of the town of Ceballos on the boundaries of the states of Durango, Chihuahua, and Coahuila. The reserve lies in a hollow or basin surrounded by small mountain ranges running more or less parallel from north to south, in the large catchment area known as Bolson de Mapimi.

Area 103,000 ha (expanded from original 100,000 ha; core area 38,000 ha)

Land tenure There are various common public lands, private ranches, and small peasant properties.

Physical features The reserve is part of the riverine basin (endorheic) system of the Mapimi Bolson of the North Mexican Central Tableland and part of the Chihuahuan Desert. Alluvial deposits predominate, consisting of recent Pleistocene gravels, clays and muds, Outcrops of igneous rock from the Tertiary period and volcanic rocks (rhyolites, andesites, and basalts) are also found. The landscape consists of isolated mountains and extensive interconnected plains.

Vegetation The reserve is located in the Chihuahua arid zone, typically represented by a restricted flora with a large number of endemics. There are five vegetation types, all generally open and xerophytic. Microphyllous matorral scrub is the most representative vegetation community, as characterised by Larreadivaricata, Agave spp., Hechtia spp., Pastinaca spp., Euphorbia antisyphilitica, and Opuntia spp.

Local human population In the early 1980s there was a total population of approximately 100 people. Of the main ranch and farm units in the reserve at this time, three were privately owned while eight were ejidos in which the land was entrusted by the government to a local community. Nine of the units were devoted to stockraising, one to the extraction of wax from candelilla, whilst 11 extracted salt from a lagoon to the north of the reserve. Agricultural development is limited.

Scientific research and facilities Research facilities include the Desert Laboratory, established in 1978 by the lnstituto de Ecologia and located on 20 ha of land in the centre of the reserve. Research includes studies on amphibians and reptiles, raptor biology, the regeneration of desert vegetation after over-grazing, fire, and various types of human activity.

Conservation management Established primarily to protect the Bolson tortoise and the fragile arid habitat. When the reserve was first established there was no zonation, but a core and buffer zone system has subsequently been established. The scientific management of the biosphere reserve is coordinated by the lnstituto de Ecologia. The local people are involved in a legally constituted association to assist in management of the reserve. This group includes representatives of the cattle ranches, small land owners ejidos, the National Council of Science and Technology (CONACYT), and the lnstituto de Ecologia.

Source: WCMC Protected Areas Database

National designations

Protected areas, defined as sites with an area of 1,000 ha or more in IUCN categories I-V (see Box 2.4), have been established in over 160 countries and play an essential role in the conservation of biodiversity worldwide (Groombridge 1992). In general, protected areas designated by national legislation have been developed to protect scenic landscapes, representative ecosystems, or

Box 2.4 IUCN Categories of protected areas (l-V) with their management objectives

I Scientific Reserve/Strict Nature Reserve: to protect nature and maintain natural processes in an undisturbed state in order to have ecologically representative examples of the natural environment available for scientific study, environmental monitoring, education and for the maintenance of genetic resources in a dynamic and evolutionary state.

II National Park: to protect natural and scenic areas of national or international significance for scientific, educational and recreational use.

III Natural Monument/Natural Landmark: to protect and preserve nationally significant natural features because of their special interest or unique characteristics.

IV Managed Nature Reserve/Wildlife Sanctuary: to assure the natural conditions necessary to protect nationally significant species, groups of species, biotic communities, or physical features of the environment where these require specific human manipulation for their perpetuation.

V Protected Landscape: to maintain nationally significant natural landscapes which are characteristic of the harmonious interaction of man and land while providing opportunities for public enjoyment through recreation and tourism within the normal life style and economic activity of these areas.

Source: IUCN (1994a)

animal populations rather than to protect individual plant species or botanical diversity. There are a few notable exceptions. Two protected areas in Arizona, USA, have been designated specifically to protect cacti. These are the Organ Pipe Cactus and Saguaro National Monuments. The former of the two protects an important example of Sonoran desert vegetation with, in addition to the organ pipe cactus Lemaireocereus thurberi, 28 other taxa of cacti occurring within the protected area.

In many other countries succulent plants occur within protected areas designated for general conservation purposes (see Box 2.2), but often full botanical inventories have not been compiled for these sites. Often it is unclear which succulent species occur within a particular protected area, and also to what extent particular rare or threatened species are actually protected in situ in various parts of their range.

At a national level, some countries have not yet developed protected area networks, and in others important areas of succulent-rich vegetation are not yet adequately represented. Most of the countries reviewed in the Action Plan have important areas of succulent plant diversity which are not yet included in protected area systems. These include Brazil, Madagascar, Mexico, Caribbean islands, Somalia, South Africa, and Zimbabwe. Recommendations for priority sites for protected areas are given in Chapter 4.

With increasing threats to succulent species in the wild and increasing land demands, implementation of recommendations for in situ protection will be particularly challenging. Novel approaches may be required. One such approach is the creation of micro-reserves specifically designed to protect endangered or endemic plant species. An example of this approach is being pioneered for endemic species in Valencia, Spain. In 1994, the Regional Government of Valencia created a new kind of legal protection, with the aim of establishing small permanent reserves for plants in need of habitat protection (Laguna 1997). More than 60 small reserves have already been created, with an individual area of less than 20 ha, and in the next few years a total of 150 micro-reserves will be established protecting 280 endemic species. The small size of each protected area is expected to reduce the risks of problems with land users. Management of the micro-reserves in Valencia is coordinated with the development of recovery plans and ex situ conservation measures. It is clearly resource and management intensive and will not be appropriate in all succulent rich areas requiring protection. Such an approach may however be appropriate, for example, for narrow endemics in parts of the Caribbean, Madagascar, Mexico, and South Africa.

The increasing availability of distribution data for succulent plant species and computerised mapping systems make it easier, in theory, to select and design areas for the protection of succulent diversity, although the actual designation of national parks and reserves remains challenging because of conflicting landuse demands. The use of geographic data from literature, herbarium specimens, and other sources to plan for the conservation of plant genetic resources is discussed by Maxted et al. (1995). Similar techniques can be used to plan conservation strategies and protected areas for rare and threatened plant species.

In Mexico, the distributions of endangered cacti in the Chihuahuan Desert Region have been mapped on a grid square basis to show the areas of maximum diversity of the species (Hernhndez and Barcenas 1995). In this way the areas of particular importance for cactus conservation are identified, as discussed further in the Mexican Regional Account in Chapter 3. Other factors would need to be taken into account in the selection of formally protected areas such as habitat diversity, presence and diversity of other species groups, and land use pressures. However, the study of the Chihuahuan Desert Region vividly highlights the fact that none of the critically important species rich quadrants identified for endangered cacti are included in protected areas.

Increasingly it is recognised that designation and management of protected areas must take into account the views and requirements of local people. The Richtersveld National Park in South Africa, briefly described in Box 2.5, was established in 199 1 following nearly 20 years of consultation with local people.

Box 2.5 Richtersveld National Park, South Africa

The Richtersveld National Park in the north-western Cape of South Africa protects an internationally important area of succulent plant diversity. The protected area was designated in 1991 after extensive local consultation. Management involves recognition of local needs with local communities involved in the decision-making process. The Park covers 1,624 km2 of attractive desert scenery and unique endemic vegetation. It is particularly important for the conservation of South Africa's mesembs, together with distinctive Aloe pillansii, A. dichotoma, A. cneyeri, and Pachypodium namaquanum. Threats to the'succulent plants have included mining, stock farming, and collection for horticulture. Tourism is now a growth industry and this in itself places pressures on the succulent plant species.

Private land

Acquisition and management of land for conservation by and individual land owners are important means of ensuring in situ conservation. In the USA, for example, The Nature Conservancy Council administers over 1300 reserves covering 650,000 ha; the National Audubon Society owns or leases over 100 sanctuaries covering over 60,000 ha; and Operation Stronghold is an alliance of 800900 private landowners who have undertaken conservation measures on private land estimated to cover 2-2.5 million ha (WCMC 1992).

In Mexico, the NGO Can Te, A.C. has a programme, 'Comprar para Conservar' or 'Purchase to Preserve', which encourages people to contribute financially toward the purchase of threatened habitats. Can Te, A.C. considers that most threatened species of cacti and other succulents do not grow in areas appropriate for national protection. In these cases, purchase of the land may be the only viable option to preserve the sites. Realistically, this can be best achieved by non-governmental organizations or by private individuals. Can Te, A.C. has purchased the terrain of Mammillaria albiflora on a barren hillside in north-eastern Guanajuato. Collectors have not appreciably reduced the population, even though it is the main known locality for the taxon. Recently, the plant was put in jeopardy when the owner of the property offered it for sale for agricultural use. However, purchasing land is not always practical. For example, the expansion of the city of Queretaro threatens to eliminate the only known remaining habitat of Mammillaria mathildae, a cactus little in demand and not threatened by collectors. An attempt by Can Te, A.C., in cooperation with the Queretaro campus of the Instituto Tecnológico y Estudios Superiores de Monterrey (ITESM), to purchase the habitat was unsuccessful due to the high prices demanded by the speculating owners.

Species management

Within areas set aside for conservation, management of the plant communities will frequently be required. Protected areas generally have management plans which set out the requirements for maintenance of the site in broad terms. For populations of individual rare or threatened species, particular management prescriptions may be necessary. As Given (1994) points out, "Particular species may be threatened or in decline because of factors that are independent of the ecosystem as a whole. Examples include harvesting, predation and the consequences of small population size. Some species may require specific habitat manipulation independent of that applied to the whole system where they occur."

Species management within protected areas may involve protection from unwanted human disturbance, with periodic monitoring or more active manipulation. Unfortunately knowledge of the biology and ecology of succulent plants species is frequently very limited, and management where it is applied is likely to be based on trial and error. Research from ex situ situations can be particularly helpful for succulent plants. Conservation of succulent plant species in the long-term will be most successfully achieved by an integrated approach involving both in situ and ex situ conservation measures.

Ex situ conservation

Edward Anderson

As seen in the introductory chapters of this Action Plan, many succulent taxa are in serious trouble, and may be lost unless immediate conservation efforts are undertaken. Cultivation of plants in botanic gardens, arboreta, private collections, and nurseries is an ex situ conservation method that is used by biologists to assure, at least, some protection of species 'away from danger'. Plant material in ex situ cultivation may be used for reinforcing existing wild populations or in the reestablishment of wild populations following the IUCN Guidelines for Re-Introductions (IUCN 1995).

In 1985 an international conference was held in Las Palmas de Gran Canaria, in which the organisations present adopted a series of 13 recommendations dealing with 'Botanic Gardens and the World Conservation Strategy.' Recommendation 4 dealt specifically with ex situ conservation. It stated (IUCN 1986):

"While that no single approach to the conservation of endangered species can be relied upon; appreciating that ex situ conservation is a necessary adjunct to in situ conservation; and acknowledging the importance of seed banks in the long-term conservation of genetic resources, The International Conference on Botanic Gardens and the World Conservation Strategy:

• Urges Botanic Gardens to recognise their responsibility to maintain, propagate and make available stock of critically threatened species for scientific and horticultural research, for reintroduction (where appropriate) and to provide suitable stock for horticulture;

Recommends that exploration and collection of species be based on concepts of infraspecific diversity so that ecogeographical diversity and diversity between and within populations be sampled in such a way that a maximum of genetic diversity be captured and stored;

Box 2.6 Recovery plan for Pediocactus knowltonii

Pediocactus knowltonii is an Endangered cactus of the USA, with only one viable population on a single hill, south of La Boca in northern New Mexico. The species was listed as Endangered under the Endangered Species Act in 1979 when only about 1000 individuals were known to remain. The decline of the naturally rare species has been caused by habitat loss, collection for horticulture and, in 1960, a misguided "rescue" operation when thousands of plants were collected from the proposed site of a dam. The Know/ton Cactus Recovery Plan approved on 29 March 1995, called for restoration of the La Boca population to approximately 100,000 cacti, long-term protection of the site, and reintroduction of the species at other suitable localities, The site is owned by The Nature Conservancy. It has been fenced to keep out cattle and in an attempt to deter collectors. The development of detailed recovery goals have been hindered by lack of biological data for the species.

Source: Endangered Species Technical Bulletin 10 (12). 1995.

I® Urges Botanic Gardens to become involved with seed conservation and recommends that the International Board for Plant Genetic Resources (IBPGR) (now the International Plant Genetic Resources Institute -IPGRI) be approached so as to establish closer collaboration on the conservation of threatened species;

Recommends that every effort be made to maintain minimal international standards for seed storage and rejuvenation;

• Recommends IUCN to continue and expand the monitoring and co-ordination of ex situ conservation, presently carried out by the Botanic Gardens Conservation Co-ordinating Body, as an integral part of the implementation of the Botanic Gardens Conservation Strategy;

Recommends Botanic Gardens and other relevant institutions to support this essential work and to provide the necessary finance for it."

As a response in part to these recommendations and because of the important succulent collections that exist around the world that could contribute significantly to the conservation of succulents, this section deals with various forms of ex situ conservation presently available for succulents. It also describes several actions that might be taken to facilitate ex situ conservation.

Conservation collections have been defined as "living collections of rare or endangered organisms, established for the purpose of contributing to the survival and recovery of a species" (Center for Plant Conservation 1991). There are four important types of succulent plant collections that may be utilised in ex situ conservation activities: botanic gardens and arboreta, seed banks, private collections, and, to some extent, commercial nurseries. Each of these plays a significant, though different role in conservation. Nonetheless, careful networking among these different collections and their managers or owners will provide botanists and conservationists with an effective tool for the long-term

The Canary Islands Crassulaceae Plants

Aeonium tabuliforme, a Rare Crassulaceae of the Canary Islands.

preservation of germplasm of rare and endangered succulents. Additionally, plant material in ex situ cultivation may be used for reinforcing existing wild populations or in the re-establishment of wild populations following the IUCN Guidelines for Re-in troductions (IUCN 1995).

Botanic garden networks

The International Association of Botanic Gardens (IABG) is an umbrella organisation for all the 1600 botanic gardens and arboreta worldwide. Some arc the traditional botanic gardens, whereas others are nature reserves, small private gardens, nurseries, and agricultural experimental stations. These institutions combined provide more than 100,000 hectares (247,100 acres) of ex situ habitat for the cultivation of plants. There are also regional associations of IABG in Latin America and the Caribbean, Asia, and Europe. In North America the American Association of Botanical Gardens and Arboreta is also active.

Following the recommendations of the Las Pal m as conference, IUCN established the Botanic Gardens Conservation Secretariat, BGCS, (which later became Botanic Gardens Conservation International - BGCI), to co-ordinate botanic gardens' conservation work worldwide. In 1985 the Secretariat published two reports of significance to succulent plant conservation: Report No. 13 of the Rare and Threatened Species of Mexican Cacti and Report No. 15 of the Succulents of Africa and Madagascar. The Botanic Gardens Conservation Strategy was published in 1989 (IUCN-BGCS 1989) and provides a rationale and basic guidelines for plant conservation work through botanic gardens. Today over 450 gardens and other institutions from 90 countries are members, and BGCI has an active programme to enhance the conservation and environmental education efforts of botanic gardens worldwide. BGCI maintains a database of rare and endangered species currently (1995) holding about 200,000 records of plants in botanic gardens, many of which are succulents.

In 1993 the IABG and BGCI signed a wide-ranging agreement "for the purposes of fostering the development of the world network of botanic gardens and arboreta, towards researching, documenting, conserving and utilising the plant resources of the world. .(Botanic Gardens Conservation News 1994).

The World Conservation Monitoring Centre (WCMC), in Cambridge, UK, maintains a database of over 100,000 rare and threatened plant taxa worldwide. Conservation biologists, particularly members of the IUCN/SSC Specialist Groups, provide data to WCMC, which in turn compiles, analyses, and supplies valuc-added information regularly to Botanic Gardens Conservation International (BGCI), the IUCN Species Survival Commission, and many other international and national organisations and institutions involved in monitoring rare plants.

In the United States the Center for Plant Conservation (CPC) was founded in 1984 at the Arnold Arboretum. Currently headquartered at the Missouri Botanical Garden, the Center is a consortium of botanic gardens and arboreta in the USA whose purpose is to preserve critically endangered plant taxa of the USA by establishing a national ex situ collection of rare plant germplasm. This National Collection is held in the Center's 25 participating institutions across the country, and is primarily composed of stored seeds which have been collected in a manner to capture the genetic diversity of a taxon to the fullest extent possible. The collection, and others like it, serves several functions: 1) as an insurance policy against extinction in case of a catastrophic loss in the wild; 2) as a source of material for research and education programs which can contribute to the conservation of a species; and 3) as a source of germplasm for potential re-introduction and ecological restoration projects, which are carried out on a cooperative basis.

Over 450 plants are currently represented in the National Collection. Of these, approximately 25 species are succulents, with the majority at the Desert Botanical Garden in Phoenix, Arizona. Genetically representative seed collections of the rare succulents have been placed in long term storage at the Desert Botanical Garden, Rancho Santa Ana Botanic Garden (California), San Antonio Botanical Garden (Texas), and Fairchild Tropical Garden (Florida). Research is conducted on germination and viability testing, propagation methods, and reproductive biology. These botanic gardens are often involved in surveying, monitoring, and re-introduction projects with federal and state agencies, as well as other partners.

National networks of botanic gardens exist in many other countries. For example, the Australian Network for Plant Conservation (ANPC) has established a programme in ex situ conservation demonstrating how botanic gardens can network effectively in conservation matters. An Endangered Species Collection was started in 1986 at the Australian National Botanic Gardens, Canberra, for research, education, display, and possible re-introduction. This collection possibly will become available to the nursery industry as well (Richardson 1992). In the Netherlands, the Dutch Botanic Garden Foundation coordinates a Decentralised National Collection amongst the Dutch botanic gardens, including very significant numbers of cacti and other succulents. Active botanic garden networks involved in conservation also operate in many countries, including Brazil, China, Colombia, Cuba, France, Germany, Indonesia, Italy, Japan, Mexico, Russia, Spain, and Portugal (Wyse Jackson 1993).

Databases

The development of the International Transfer Format for Botanic Garden Plant Records (IUCN-BGCS 1987) and computer-based plant collection software systems have provided the means for, and been influential in, the development and improvement of plant records and collection documentation worldwide.

One of the most serious problems facing conservationists is that of nomenclature. Some rare succulents are referred to by a variety of names; for example, the Office of Scientific Authority of the US Fish and Wildlife Service and the CPC continue to use the nomenclature of Benson (1982) for cacti in the USA, although CITES has now published an updated checklist of the most commonly accepted names of cacti based on recent research (Hunt 1992). In an effort to assist scientists and horticulturists in dealing with the perplexing problems on nomenclature, the contents of all issues of the Repertorium Plantarum Succulentarurn (RPS) have been compiled by the Stadtische Sukkulenten-Sammlung Zurich (ZSS), creating the RPS/ZSS Database. Not only does this database contain thousands of names, but it also contains curatorial information as needed for living and herbarium collections. The following custom-designed printouts are available: taxonomic data by family, taxonomic data by genus, and synonymy of a genus. Such synonymy lists are available for most succulent families. Additional lists are published in the annual issues of the IOS Bulletin.

Collecting

The CPC (1991) has published guidelines for collectors of rare plants in response to some concern about inadequate genetic representation of endangered species in ex situ collections. The guidelines address five questions which constitute a natural hierarchy covering species, populations (and ecotypes), individuals, and alleles. The work of the collector may also be influenced by the degree of genetic difference among populations, time and money considerations, the survival rate of propagules, and the intended use of the collections. The Center's five sampling questions are:

Which species should be collected? The two most important criteria here are the probability of loss of a unique genepool, and the potential for restoration or recovery.

2) How many populations should be sampled per species? As a rule, one to five ecotypes or populations should be sampled, depending on the population history and the degree of difference among the groups.

3) How many individuals should be sampled per tion ? Ten to fifty individuals should be sampled per population, but this depends on population size and genetic mobility.

How many propagules should be collected from each individual? From one to twenty should be obtained, depending on the survival rate of the propagules and the long-term needs of the collection. 5) Under what circumstances is a multiyear collection plan indicated? More than one year is recommended, especially if the desired number of propagules cannot be removed safely without affecting the reproductive capabilities or demography.

Developing techniques, particularly for DNA study, for the analysis of genetic variability of plant populations in the wild and maintained ex situ provide valuable means for improving the genetic representation in garden collections. Such techniques are also becoming useful for conservation, to study material from garden sources (from botanic gardens, private growers, and commercial sources) that has lost its documentation.

Seed banks

There is an increasing number of seed banks being developed for wild plants worldwide, particularly by botanic gardens, although there is still relatively little coordination between them. A 1994 survey by BGCI indicated that there are currently over 150 such seed banks in botanic gardens. The extent to which succulent species are contained within their collections is unknown, however. One such collection specialising in the storage of arid land species is held at Wakehurst in the UK, and a second by members of the CPC in the US where seeds from the National Collection of endangered plants are desiccated and frozen for long term storage of the germplasm.

The collection and ex situ storage of seeds of rare plants present several significant conservation problems. The first concerns the impact of collecting seeds on the natural populations. This is of special concern with respect to succulents occurring in arid regions, for the severe climatic fluctuations in deserts frequently lead to sporadic reproduction. Thus, collection of seeds from plants with low levels of reproduction during periods of stress can be highly detrimental to the long term survival of that population. IUCN-BGCS (1989) recommends that never more that 10 per cent of the seed available in a wild plant population should be collected.

A second concern, expressed by Richardson (1994), involves the exchange of seeds in Index Seminum programs in which weedy plants are distributed with insufficient controls. Thus, exchange programs by botanic gardens with good intentions may result in the introduction of potentially dangerous exotic plants. The CPC has recognised the problems, both potential and real, of seed banks and the exchange of seeds, and has published extensive guidelines for the management of "orthodox" seeds (those that tolerate severe desiccation or dehydration and which can usually be stored for long periods of time) (Wieland 1995). These guidelines deal with the collection, storage, and shipment of seeds. Much information on the management of seeds has also been published by IPGRI.

Seed collections are a significant aspect of ex situ rvation, for they p ermplasm other than from the field guidelines are followed, seed banks and Index Seminum exchanges can play an important role in perpetuating rare succulents, as well as providing research and horticultural materials. The National Botanical Institute of South Africa (NBI), including its network of botanic gardens has a seed exchange programme with other institutions; seeds are exchanged "on the understanding that it is not used commercially." These seed collections can also be valuable to some in situ conservation projects which involve re-introduction of plants into habitat. Those organisms placed in habitat may have originated from seeds propagated in either botanic gardens or commercial nurseries. Guidelines for such plant re-introductions have been produced by several organisations, including the IUCN-SSC Re-introductions Specialist Group (IUCN 1987 and 1995), and the Handbookfor Botanic Gardens on the Re-introduction of Plants to the Wild has been published by BGCI (Akeroyd and Wyse Jackson 1995).

Botanic gardens

A wide range of botanic gardens maintain very extensive collections of succulent plants. Compared to many other plant groups, the rare and endangered species of cacti and succulents are well represented in many collections. A few of these gardens grow collections of the succulent members of their own flora, e.g. the Jardín Botánico Canario 'Viera y Clavijo', Gran Canaria, Spain; the National Botanic Institute, South Africa; and the Kings Park and Botanic Garden, Perth, Western Australia. However, the succulent collections of most botanic gardens are of exotics. There are also many regions of natural succulent vegetation, such as Ethiopia, Somalia, Chile, where there are no functioning ex situ conservation facilities. The development of local facilities and expertise should be emphasised in plans to establish new collections. Collaborative training programmes between the larger international botanic gardens and local facilities should occur.

The following eight examples are from botanic gardens that have already shown leadership in managing collections of succulents, and are actively involved in conservation work.

1. University of California Botanical Garden U C

Berkeley, Centennial Drive, Berkeley, California 94720, USA. Telephone: (510) 6438040. FAX: (510) 642-5045.

Founded in 1890, this state supported garden is part of the largest university campus in the USA. The garden, located in Sycamore Canyon above the main campus, has an area of 13 hectares (32 acres). The succulent collection comprises a fifth of the total collection. There are 2570 comprising 4046 accessions, with 2293 species of the families Agavaceae, Aizoaceae, Cactaceae, Crassulaceae, and Aloe (included in Liliaceae in their data base). Of these, 69 per cent of the taxa are documented (78 per cent at the species level). The Berkeley garden also has living material of 45 species of CITES Appendix I succulents. It is a participating member of the CPC. Living material of the following collectors of succulents are present in the garden: M. Cardenas, S. B. Hogan, P. C. Hutchison, A. Lau, R. Moran, M. Kimnach, W. Krahn, F. Ritter, R. Rodin, and J. West.

2. Desert Botanical Garden 1201 North Galvin Parkway, Phoenix, Arizona 85008-3490, USA. Telephone: (602) 941-1225. FAX: (602) 481-8124.

This garden is a private institution and was founded in 1937. It covers an area of 53 hectares (145 acres), with most specimens planted outside. There are also three glasshouses and an extensive shade house. The Garden's succulent collection contains the following specimens:

Family

No. taxa

No. taxa documented

Agavaceae

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