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The case studies below include examples submitted from individual specialists, and examples selected from the literature.

Teak conservation project in the Philippines

The Philippine Plant Specialist Group of the IUCN Species Survival Commission (SSC) is undertaking conservation of the Philippine teak (Tectona philippinensis), an endemic and threatened tree species found along highly disturbed forest edges on limestone along the seashores of Batangas and in Iling Island, Mindoro. This tree produces hardwood used by the local people for house construction, furniture, and high-quality firewood. The species is currently threatened by habitat destruction, overcollection, and by occasional fires. Moreover, immature teak trees are preferred for building material, thus threatening the reproductive capacity of the population. This project, funded partly by Flora and Fauna International under the Flagship Species project, and the Philippines National Museum, started in 2001 and will continue for two years. A conservation program is being proposed to ensure the reestablishment of a stable natural population, and includes setting up long-term ecological research, establishment of a recovery and management program, public education, community consultation, and resource stewardship, and policy initiatives. (Thanks to Domingo Madulid, chair of the IUCN/SSC Philippines Specialist Group.)

Conservation of the lady's slipper

Cypripedium calceolus, commonly named lady's slipper, is the most spectacular of all Swiss orchids and also the most endangered, with marked decrease in the size and number of populations. Habitat destruction, habitat alteration, and overcollection are the main causes of the decline. People now seem to be more aware of the damage they can do by picking plants, or even only flowers, since they will then not produce any seeds. But man is not the only enemy: the chamois deer, for example, find orchids a delicacy and therefore are capable of exterminating all the lady's slippers in a particular habitat in just a few years. Chamois and Cypripedium calceolus are both protected by law . . . so is there a problem? Encouraging results elsewhere led to the creation of Fondation Orchidée, supporting a project to reintroduce C. calceolus to le Chasseral in the west of Switzerland, where environmental damage had led to its disappearance. After studying the inventory of existing and extinct populations of C. calceolus in Cantons of Bern, Fribourg, and Neuchatel and making an ecological study of the habitats, the project leaders selected healthy plants in a habitat very similar to and close to le Chasseral. Plants were hand-pollinated and seeds collected for germination in the United Kingdom. After germination, plants were sent back to Switzerland, where they were refrigerated at 4°C for about twelve weeks to simulate winter, then potted in soil and covered with pine needles to protect them from excess heat or cold. Plants are repotted each year and will bloom after 5 to 7 years. When they flower for the first time they will be reintroduced to le Chasserai, where the ecological conditions are most suitable. With the help of the Swiss conservation organization Pro Natura and forest guards, the new habitats will be protected by a fence, and the chamois will be kept away. The new populations will be monitored for evaluation. (Thanks to Vinciane Dumont, Fondation Orchidée.)

Xanthocyparis vietnamensis, a new but threatened genus of conifer

It rarely happens that a new conifer discovery turns out to be sufficiently distinct to be a new genus. Since the addition of Metasequoia in the 1940s, there have been only two: Cathaya in the 1950s, and Wollemia in 1994. In October, 1999, a botanical survey to the Karst Mountains in the far north of Vietnam, on the border with Yunnan (China), came upon an unknown conifer, which could only be identified to the family Cupressaceae. At first, not much material was collected, but a second visit to the site, high on a steep limestone ridge, yielded good herbarium samples; botanists then set to work to determine its identity. Other information was gathered by some of the botanists involved in the field work. As was the case with the other newly discovered genera, by the time botanists had found this Vietnamese conifer, it was virtually on the brink of extinction. Similar to the Chinese Thuja, only small trees seem to remain high on steep rocks, while evidence of a similar type of forest on lower slopes strongly suggests it could have grown there as well in the past. Villagers know of the tree and its valuable wood, and confirm that good trees are now almost completely gone. The forest is disappearing now even from the steeper slopes. It is not known how many trees are left, but it cannot be many. They seem to be restricted to a single mountain ridge. Therefore, this conifer has been classified as Critically Endangered (CR) in the IUCN Red List system. (Thanks to Aljos Farjon, chair IUCN/SSC Conifer Specialist Group.)

Rediscovery and protection of an "extinct" plant in California

Some 26 miles from downtown Los Angeles are some of the last remaining remnants of southern California's ancient oak woodlands and native grasslands. In May, 1999, a team of botanists investigating these discovered a species thought to be extinct, the San Fernando Valley spine-flower (Chorizanthe parryi var. fernandina). The site is on a ranch that was scheduled for residential and commercial development from 2001. Five plant communities had been identified as "sensitive", according to the California Natural Heritage Database, a statewide inventory of the locations and condition of the state's rarest species and natural communities. A number of other rare species were found during the survey including valley oak, blue oak, and Californian melica. The spineflower was formerly known from only eleven sites, and prior to this new sighting had not been seen since 1929. In August, 2001, the developers, Ahmanson Land Company, announced that they had agreed to set aside a 330-acre preserve for permanent protection of this plant. The new preserve would be adjacent to 400 acres maintained in a natural state, and would protect almost 1.6 million plants—more than 90 percent of the occupied habitat and population as mapped [see reports in Plant Talk 19 (1999) and 26 (2001)].

Rediscovery and protection of a lost Mauritius endemic species

The flora of Mauritius is one of the most endangered in the world, with nearly three hundred species threatened. The major threat is invasive weeds that have taken over almost all natural habitats. Trochetia parviflora (family Sterculiaceae) is a small tree that is endemic to Mauritius and had not been seen since 1863. In the course of a botanical survey in early 2001, a plant of T. parviflora was discovered growing on steep cliffs in a nature reserve on an isolated mountain. Fortunately, the plant is not facing strong competition from invasive plants, as it is isolated on a rocky ledge. But only a few meters away are dense thickets of invasive Schinus and Hiptage. Subsequent searches found a further fifty-three wild individuals, but of the fifteen adult plants found only three were producing seedlings. The main reasons for its lack of reproduction appear to be invasive alien weeds, monkeys, and rats. A grant from the Chicago Zoological Society will help save the plant by allowing weeding of the immediate vicinity, but there is need for greater funding to ensure in situ conservation and survival of the species [see report by Vincent Florens in Plant Talk 24 and 25, (2001)].

Parque Nacional Cordillera Azul, Peru—a plant-diverse park

The Cordillera Azul contains a diversity of habitats rich in unique plant and animal species, and on account of this has been identified as an a priori area for conservation. In August/September, 2000, a team of scientists carried out rapid inventory for three weeks, and recorded 1,600 of the estimated 4,000 to 6,000 species thought to occur in the region. Following recommendations from this survey, in May, 2001, the government of Peru established the Parque Nacional Cordillera Azul. The mountain complex in the park encompasses a wide range of habitats, including jagged peaks, tall lowland forests, elfin forest shrublands and meadowlands, and high altitude wetlands. Many of these ecosystems are very rare and unprotected elsewhere. A remarkable feature is the diversity of palms with forty-five of the 105 palm species known in Peru being found in the area. A number of new species were discovered, including a small daisy tree, a large-stemmed Zamia (cycad), and three palms. A small fern (Schizaea poepigiana) that was found during the survey had not been seen since 1929. Threats from logging have been averted, since the region was declared a national park. The creation of this park shows that there are still opportunities to act before habitat fragmentation and degradation transform the landscape [see report by Jane Villa-Lobos in Plant Talk 25 (2001)].

Garden genes conserve threatened plants

Garden plants often exhibit limited genetic variation, and this is often cited as evidence for the limited role of gardens in conserving wild species. However, a study of genetic variation among cultivated plants of the threatened Chilean climber Berberidopsis corallina has revealed a surprising amount of genetic variation. Analysis of the DNA of thirty-five cultivated samples revealed sixteen different genotypes, suggesting that the original introductions by Veitch and Sons Nursery in 1862 was through seed, rather than cuttings. In the wild, the species has disappeared through much of its range, and conifers introduced for forestry have replaced much of its wild habitat. Garden plants therefore comprise a significant off-site gene pool, and a good potential source of material for reintroduction into the wild [see article by Martin Gardner in The New Plantsman 7 (2000), pp. 174-177].

Conserving furtive flowers—the Hydnoraceae

The family Hydnoraceae has only two genera and a small number of species, mostly plants of arid lands. These plants spend their whole life underground as root parasites; only the flower emerges from the soil. One of the most remarkable is Hydnora triceps. The dominant vegetation in its native habitat in Namaqualand, South Africa, is shrubby Euphorbia, one species of which is a host for the parasite. H. triceps had been rarely collected since its discovery in the early 19th century, and although thought to be extinct, was collected during a survey in 1999. One of the amazing things about this plant is that it flowers underground, punching up through the soil so that it can be pollinated by flying insects. But it also has an underground "chamber flower" that may be pollinated by weevils and nitulids, as has been shown to occur in the similar species Prosopache americana. No fruits have ever been described, although fruits are known to local shepherds, who eat them roasted. No way is known yet of growing this species in gardens, so its preservation depends on maintaining its wild habitat. Apart from the problem of knowing little of its ecology and reproduction, the region is highly threatened by diamond mining. Also, poisoning of predators of livestock could impact the small mammals that feed on the fruits and scatter the seeds. "Out of sight, out of mind" is not a good policy for ensuring the future of one the planet's most curious plants [see report by L.J. Musselman and P. Vorster in Plant Talk 21 (2000)].

Mutinondo (Zambia)—combining conservation and low impact tourism

The Mutinondo Wilderness Area is a 10,000 ha rare treat for the botanist. It is a concession being developed for low-impact tourism in Zambia's northern province. The developers have restricted development to a single road in and out of the area, and to camping facilities. Perhaps the most striking feature are the inselbergs— granite peaks where plants must either find a way to the soil below, or survive in dewfall in the dry season. The miombo woodland of this remote part of Zambia is largely free from human disturbance, and is rich in plant species that are less common elsewhere. The area also includes riparian forest and numerous "dambos" that are seepage zones of edaphic grassland. The uniqueness of this site stems partly from the habitats it protects, but also from its history of isolation—despite deep granite soils, this area has been uninhabited for many generations. The result is a pristine miombo wilderness unrivalled in this part of Africa, and now available for low-impact tourism visits [see report in Plant Talk 20 (2000)].

Preserving the Badgeworth buttercup in Britain

A classic example of setting up a species reserve to protect a rare wild flower concerns Adderstongue spearwort (Ranunculus ophioglossifolius). This occurs at Badgeworth in Gloucestershire, U.K., famous as "the world's smallest nature reserve" in the Guinness Book of Records. The reserve was created in 1932 and fenced to exclude grazing, but the buttercup rapidly declined. In five of the years between 1934 and 1962, no plants at all occurred in the reserve; in only two of the years were there one hundred or more plants. In 1962, it was realized that young plants could not develop in the dense tangle of vegetation that had developed. Ecological research also established that the plant likes warm, long summers, and that there is an essential role played by standing water. The plant is adapted to shallow pools that flood in late autumn, but partly dry out in late summer. It also needs a sufficient depth of water in winter to protect growth points from frost. It is this kind of autecolog-ical (single species) research that can often greatly help scientists understand what is needed to look after species in nature reserves. The local villagers have taken the buttercup to their hearts, and for some years a Buttercup Queen was crowned at the village fete with a garland of flowers [see report by Peter Marrin in Plant Talk 19 (1999) ].

Protecting the "living dead": Muehlenbeckia astonii (Polygonaceae) in the South Island, New Zealand pastoral farmlands

M. astonii, or shrubby tororaro, is a medium- to large-sized shrub found in four discrete areas: coastal Wellington, northeastern Marlborough, north Canterbury, and Kaitorete Spit, just south of Christchurch. In total, about 2600 plants have been found, of which over 90 percent are known from one site. Shrubby tororaro was not included on threatened plant lists until the late 1980s, a reflection of both its wide distribution and, until recently, the few times it had been seen in the wild. In North Canterbury and Marlborough provinces, it has a particularly fragmentary range that reflects profound land use modification and loss of habitat. One of the remarkable features of this species is that virtually no site preserves the original habitat. Muehlenbeckia astonii is a valuable horticultural plant with great potential as a shrub for hedges and stock shelter in drier parts of the South Island. During severe droughts of the 2000-2001 summer it showed no signs of obvious drought stress, when many exotic species and even some indigenous species showed considerable drought stress. This provides a potential selling point for its reestablishment on both private and public land. A concern regarding the future of this species is that reproduction is practically unknown. Flowers are either females or inconstant "males," and seeds are produced where there is opportunity for cross-pollination. It is assumed at the present time that existing wild plants largely represent an aging cohort of currently unknown longevity. (Given 2001)

Brighamia in the Hawaiian Islands

Brighamia, an endemic genus with two critically endangered species in the Campanulaceae, survives on the high sea cliffs of Hawaii. Brighamia insignis, which was last seen on Ni'ihau in 1947, is currently known from two separate populations on Kaua'i. Those populations occur along the Na Pali coast of northwest Kaua'i, and include five plants on the Hoolulu cliffs and two plants on the headland cliffs of Waiahuakua. A third population, on the southeast side of Kaua'i along the basalt cliffs of the Haupu Range and above the Huleia River, has recently gone extinct. That population consisted of twelve individuals in 1990. Recent inventories of Brighamia insignis by National Tropical Botanical Garden (NTBG) staff estimate a total of only seven wild plants remaining. This is a catastrophic drop in numbers from the 1990 inventory that estimated ca. 142 individuals, and totals a loss of 95 percent (135 individuals) of the wild Brighamia insignis population. Brighamia rockii is now extinct on Lana'i and Maui, and is presently known only from the northern sea-cliffs of Moloka'i, which are considered the tallest in the world. A population inventory made in 1990 estimated approximately 173 individuals of Brighamia rockii within six naturally occurring populations, which included the basalt cliffs of Haupu Bay, East & West Wailau, Anapuhi, Waiehu, and Huelo Islet. A recent survey found only eight plants on Huelo Islet and seventy plants at Haupu Bay. The wild populations of both species are setting very little seed, it is hypothesized that the endemic pollinator, thought to be a hawk moth, has declined to such a point that pollination is not occurring. Conservationists have been hand-pollinating the surviving populations. Abundant seed has been generated, and managed populations of B. insignis have been successfully established at coastal sites on Kauai, most notably the Limahuli Botanic Garden and Preserve and the Kilauea National Wildlife Reserve. Two more populations are planned in the near future. (Thanks to Mike Maunder, Royal Botanic Gardens, Kew.)

Hyophorbe lagenicaulis: a Round Island endemic, Indian Ocean

Endemic to Round Island, off the north-east coast of Mauritius, this extraordinary palm may have originally occurred on mainland Mauritius and some of the small offshore islets, such as Ile aux Aigrettes. The wild population on Round Island has decreased dramatically over the last 150 years following the introduction of goats and rabbits. Travelers' reports and photographs from the 1920s suggest that this species was an abundant component of the island's palm woodland. Following conservation concerns expressed by the Government of Mauritius and the Jersey Wildlife Preservation Trust (now Durrell Wildlife Conservation Trust), the island was cleared of goats and rabbits; this resulted in a dramatic recovery in both plant cover and the endemic reptilian fauna. About fifteen individuals were recorded in 1978, dropping in 1986 to only eight adults and twenty-seven seedlings. Subsequently, through natural regeneration the population has increased, with about 350 seedlings observed in 1999. In addition, seeds have been planted and distributed around the island during management trips. With only one wild population, it was regarded as prudent to establish new populations on rat-free offshore islands. Accordingly, this species has been introduced onto Ile aux Aigrettes as part of a long-term restoration program. The older plantings at the Pamplemousse Botanic Garden are derived from nineteenth and early twentieth century wild collections made on Round Island prior to the population bottleneck. An initial genetic screening of wild and cultivated stocks is being used to plan the supplementation of wild populations with old cultivated sources. (Thanks to Mike Maunder, Royal Botanic Gardens, Kew.)

Maintenance of Lythrum hyssopifolia in agricultural landscapes in Britain

Lythrum hyssopifolia (hyssop loosestrife) is a widespread annual species, but in Britain it is sufficiently rare to be included in the British Red Data Book. Like many species found in pioneer vegetation on exposed mud, it has diminished in frequency. In recent years it has been confined to only one site in Cambridgeshire and in the Channel Islands, where it occurs locally in shallow depressions in arable fields. It is dependent on both winter flooding and regular ploughing of these sites for its survival. Lythrum is able to persist because the combination of local topography and agricultural practice favors an annual plant of low long-term competitive ability. Annuals predominate in this highly disturbed habitat. They germinate mostly in spring, most are self-pollinating, and have potential longevity of seeds (an advantage, as sites may not be flooded or disturbed every year). Lythrum was absent from one site for three years because winter flooding did not occur. The habitat is highly specialized, and its survival (along with the species found there) depends on the peculiar combination of flooding and disturbance. (Preston and Whitehouse, Biological Conservation 35 (1986), 41-62.)

Reestablishment of the extinct native plant Filago gallica L. (Asteraceae), narrow-leaved cudweed, in Britain

Reintroduction was used for the rare annual narrow-leaved cudweed (Filago gallica L.), under Plantlife UK's Back from the Brink project. The species had been recorded in about thirty confirmed sites, mainly from sands and gravels in southeast England. It became extinct in England in 1955, but survived in one site on Sark, Channel Islands. Native mainland material of F. gallica had been maintained in cultivation since 1948, and provided an opportunity to reestablish the plant. Historical records were used to help plan the reintroduction; these indicated that it used to be found on light sandy/gravelly soils, in areas with a high summer temperature, in open vegetation usually with other Filago species. Pot-grown plants and seed were reintroduced to the wild in 1994 at the last known site, and by 1998 the species was successfully reestablished and continues to do well (Rich, Gibson, and Marsden 1999).

Rediscovering obscure members of the carrot family: The role of amateur botanists

Flora Europaea describes 423 species of the carrot family (Apiaceae) in 110 genera. Many are well known, but between forty and fifty of these species are very poorly known, and some have not been seen in the wild for many years. One example is Peucedanum achaicum from southern Greece. The original site is described as being on cliffs in the Vouraikos Gorge below Zachlarou, but in a country where detailed maps were hard to obtain until recently, finding such a site may not be easy. Zachlarou is a monastery with a station on a cog railway, but penetration of the gorge below the monastery revealed a talus slope with many plants of this species. The genus Seseli (moon-carrot) is rich in obscure species, with one which had even been thought to be extinct. But assiduous exploration revealed 600 plants of this species in the Sierra de Gador of Spain. One of the problems is that rare and obscure species may be accompanied by much more common species, adding to the confusion. This is the case with Seseli tomentosum, which occurs in Croatia and is easily confused with the much more common S. montanum subsp tommasinii. The lesson is to have good knowledge of what such plants look like, and to undertake fieldwork [see report by Mervyn Southam in Plant Talk 11 (1997)].

Cloning the Mascarene café marron

The islands of Mauritius, Rodrigues, and Réunion (Mascarene Isles) are famous for their endemic plants. One of the very rarest is the café marron (Ramosmania rodriguesii) in the family Rubiaceae. It is reduced to just a single wild tree, which was discovered by a schoolboy in 1980. The Rodrigues Forestry Service put a fence around the tree to save it from being hacked at or cut down. Continuing damage meant that eventually the tree was protected by three more concentric fences and two padlocked gates. In 1986, a cutting was taken to the Royal Botanic Gardens, Kew, from which a number of plants were propagated. An attempt to repatriate the plant in 1989 failed. In 1996, further cuttings were taken and successfully rooted on the island. This will now provide the basis for a new generation of plants to be placed back into the wild. Other good news from the Mascarenes is that several other plants feared to be extinct have been found in the wild and will now be propagated. One of these is Trochetia parviflora, a small tree found on Mauritius that had not been seen since 1863 and was feared extinct [see reports in Plant Talk 12 (1998) and Plant Talk 24 (2001)].

Collapse of ant-plant mutualisms through competition

Sometimes invading species can have a devastating effect on the reproduction and eventual survival of plants. An example comes from the unique southern African fynbos flora. Indigenous ants are important seed dispersers, taking seeds for food and storing them in their nests, where a proportion eventually germinates. Invasion by the Argentine ant (Iridomyrmex humilis) has resulted in a dramatic drop in indigenous ant numbers. Whereas seedling emergence of Mimetes cucullatus (family Proteaceae) was 35 percent in sites not infested by Argentine ant, where the ant has invaded this has dropped to 0.7 percent. It is predicted that continued invasion of fynbos by these ants will lead to eventual extinction of a number of fynbos endemic shrubs by slow and subtle attrition of seed reserves.

Creating a new population of the desert endemic annual: Amsinkia grandiflora

Amsinkia grandiflora (family Boraginaceae) is an endangered annual plant known only from three natural populations in the dry grasslands east of Livermore, California. Current threats are both intrinsic (low genetic variability, low seed production, and specific habitat requirements) and extrinsic (exotic grasses, livestock grazing, and intensive land use). Using existing data on ecology and distribution, the natural range of the species was evaluated and twelve candidate sites selected, with one being chosen for the first experimental introduction. A total of 3460 nutlets were sown into twenty plots that were given a variety of treatments (burnt, hand-clipped, grass-specific herbicide) to keep down weed competition. Sowing of nutlets was done using frames that allowed the fate of individuals to be followed. Success was evaluated by measuring germination, stress, survivorship, nutlet production, and demography. Overall, the new population was successful. Of the 3460 nutlets, 1774 produced germinules in the first season and 1101 survived to reproduce. From these, over 35,000 nutlets were produced. Prior to the second growing season, the new population was divided into two treatment blocks—one being burnt in the fall and sprayed with grass herbicide in late winter, while the other was herbicide-sprayed only. Nutlet production grew by 44 percent. By next spring there were 1640 reproductive plants in the population. This demonstrates that even for precarious species, sites for new populations can be located and planted, evaluated, experimentally treated, and managed to a recovery phase ( Pavlik 1994).

Saving the "Wooden Rhino": making the Kenyan woodcarving industry sustainable

The Kenyan woodcarving industry has been a rural development success. Ironically, the economic success of this industry has severely undermined the natural resource on which it is based: slow-growing hardwoods such as ebony (Dalbergia melanoxylon) and "muhugu" or mahogany (Brachylaena huillensis). As a result, the livelihoods of 60,000 carvers and their families, as well as globally-important forest biodiversity, are under threat. The felling of over 50,000 trees per year for carving alone poses a major conservation problem, because it degrades forest habitat. Carvers are aware of the threat to their livelihoods and have identified fast-growing tree species that can be sustainably harvested, such as neem (Azadirachta indica), as alternatives. The People and Plants Initiative of WWF-UK, UNESCO, and the Royal Botanic Gardens, Kew, has been promoting the use of such "Good Woods" for a number of years. Stumbling blocks exist, though. For example, carvers are used to carving hardwoods and, at present, have few incentives to make the switch. Carvers can still buy hardwood, illegally-cut elsewhere, for little extra cost compared to Good Woods. In contrast to Good Woods, hardwoods do not have to be cured before carving. However, a strong, market-led demand for Good Wood carvings could change their practices. The carvers are very responsive to trends in demand. People and Plants is working with the carvers and farmers' group towards Forest Stewardship Council certification, which could prove a pivotal tool, allowing the economic benefits of carving to continue to accrue to the carvers and farmers, while helping to conserve the environment (see People and Plants project, www.kew.org/peopleplants).

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