Globally Threatened Amphibian Species Part 1

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196 Threatened Amphibians of the World VU Melanophryniscus montevidensis (Phillippi, 1902) Vulnerable A2ac; B1ab(iii,iv,v) Order, Family: Anura, Bufonidae Country Distribution: Brazil, Uruguay Current Population Trend: Decreasing © Axel Kwet Geographic Range This species is restricted to coastal Uruguay (Montevideo, Canelones, Maldonado, and Rocha Departments) and adjacent Brazil (one locality in Rio Grande do Sul state). It occurs at sea level. Population This species is in decline in some areas and extirpated in others. Nevertheless, it is still common at several localities. Habitat and Ecology It is a diurnal species inhabiting coastal sand dunes. It is an explosive breeder, and may be found in large numbers in temporary pools after heavy rains; the larvae develop in these pools. It is not tolerant of habitat disturbance. Major Threats The major threat to this species is habitat loss due to human settlements, exotic tree plantations, and the drainage of wetlands. Conservation Measures It does not occur in any protected areas, and there is a need for improved protection of sites at which this species is known to occur. Notes on taxonomy: Elevated to full species status by Klappenbach and Langone (1992). Bibliography: Klappenbach, M.A. and Langone, J.A. (1992), Langone, J.A. (1994), Maneyro, R. and Langone, J.A. (2001), Tedros, M., Kolenc, F. and Borteiro, C. (2001) Data Providers: Jose Langone VU Melanophryniscus orejasmirandai Prigioni and Langone, 1986 Vulnerable D2 Order, Family: Anura, Bufonidae Country Distribution: Uruguay Current Population Trend: Stable Geographic Range The type locality of this species is Sierra de Ánimas, Maldonado Province, Uruguay, at an elevation of 350-500m asl. It occurs in an area of less than 10km². Population It is common at its only known locality, and has not undergone any change in population size in 10 years of monitoring from 1990 to 2000. Habitat and Ecology It occurs in grasslands and rocky outcrops, and reproduces in permanent small streams. Its tolerance to habitat disturbance is unknown. Major Threats Although there are currently no major threats to the species, habitat loss and degradation due to wood plantations and touristic activities might result in declines in the future. Conservation Measures It does not occur in any protected areas. This species requires continued close population monitoring particularly since it is known only from a single location. Bibliography: Langone, J.A. (1994), Maneyro, R. and Langone, J.A. (2001), Prigioni, C.M. and Langone, J.A. (1986) Data Providers: Esteban Lavilla, Jose Langone VU Metaphryniscus sosae Señaris, Ayarzaguena and Gorzula, 1994 Vulnerable D2 Order, Family: Anura, Bufonidae Country Distribution: Venezuela Current Population Trend: Stable Geographic Range This species is known only from the type locality, on top of Cerro Marahuaca, in Amazonas state (03° 40’N; 65° 27’W), at 2,600m asl, in Venezuela. Population The population status of this species is not known. Habitat and Ecology It inhabits high montane tepui habitat. It breeds by direct development, perhaps with internal fertilization. Major Threats There are no current major threats, but its restricted range makes it susceptible to threatening processes such as wildfire. Conservation Measures There is a population within Parque Nacional Duida-Marahuaca. There is a need for close population monitoring of this species, particularly since it is restricted to a single location. Bibliography: Barrio Amorós, C.L. (2004), La Marca, E. (1997), Señaris, J.C., Ayarsagüena, J. and Gorzula, S. (1994) Data Providers: Enrique La Marca, Celsa Señaris CR Nectophrynoides asperginis Poynton, Howell, Clarke and Lovett, 1999 “1998” KIHANSI SPRAY TOAD Critically Endangered B1ab(ii,iii,v)+2ab( ii,iii,v) Order, Family: Anura, Bufonidae Country Distribution: Tanzania Current Population Trend: Decreasing CITES: Appendix I © Timothy A. Herman / Toledo Zoological Society Geographic Range This species is only known from the Kihansi Falls, in the Kihansi Gorge, in the Udzungwa Mountains, eastern Tanzania, at 600-940m asl. Its global range covers a tiny area of just two hectares around the Kihansi Falls, and searches for it around other waterfalls on the escarpment of the Udzungwa Mountains have not located any additional populations. Population It was formerly abundant in a tiny area, with a population of around 17,000 animals. Reports indicate that the species fluctuated naturally in its population size. The population appeared to be at a high in May 1999, at a low in 2001 and 2002 (when the population was estimated at 1,000 animals), and at a high again in June 2003, when perhaps as many as 20,000 individuals survived. However, subsequently the population went into steep decline, and by mid-January 2004, only three individuals could be seen and just two males were heard calling. There were a few records of calling animals during the rest of 2004, and an unconfi rmed report from January 2005, but there are no records of any individuals since, despite surveys, and the species might now be extinct in the wild. Habitat and Ecology It lives only in soaked herbaceous vegetation in the spray zone of the Kihansi Falls. It breeds by internal fertilization, the females retaining the larvae internally in the oviduct until little toadlets are born. Major Threats The serious decline of this species appears related to the Lower Kihansi Hydropower Project, involving the construction of a dam in 2000 upstream on the Kihansi River, which cut off 90% of the original water flow to the gorge, thereby hugely reducing the volume of spray, particularly in the dry season, as well as altering the vegetational composition. An artificial gravity-fed sprinkler system was set up to mimic the natural spray of the Kihansi ecosystem with the remaining water flow. Unfortunately, the sprinkler system was not ready by the time the water was cut off in 2000, and by the time the sprinklers came on nine months later the ecosystem had already dried up (see Krajick 2006). Later, during the dry season in 2003, the artificial sprinkler system failed for a while. Around this time, the fungal disease chytridiomycosis was confirmed in dead animals of this species, and this disease is probably responsible for the final population crash. It is possible that the drought caused by the failure of the sprinkler system resulted in stress to the animals that rendered them susceptible to the disease. There are also reports that the 2003 crash coincided with a brief opening of the dam’s fl oodgates to flush sediments; tests showed that these contained pesticides used in maize farming operations upstream, in concentrations sufficient to kill the toads (Krajick 2006). Conservation Measures It is not known from any protected areas. Sufficient minimum bypass flow from the dam is required to maintain the spray habitat. An artificial sprinkler system is in place, and this is especially important in the dry season. Captive breeding is ongoing in Toledo and New York Bronx Zoos. The captive population has fluctuated as husbandry problems have been encountered and addressed (animals were initially plagued with various infections and nutritional deficiencies), but currently stands at about 300 individuals. Investigations are urgently needed to determine whether or not any individuals survive in the wild, and whether or not chytridiomycosis is still present in any remaining individuals. Bibliography: Krajick, K. (2006), Poynton, J.C. (1998), Poynton, J.C. (2003b), Poynton, J.C. et al. (1998), Quinn, C.H. et al. (2005), Zippel, K. (2005) Data Providers: John Poynton, Kim Howell, Alan Channing, Simon Loader, Michele Menegon
Globally Threatened Amphibian Species 197 EN Nectophrynoides cryptus Perret, 1971 Endangered B1ab(iii) Order, Family: Anura, Bufonidae Country Distribution: Tanzania Current Population Trend: Decreasing CITES: Appendix I Geographic Range This species is known only from the northern part of the Uluguru Mountains in Tanzania where it has been recorded at 600-2,200m asl. Population There have been no records of this species since the original collections of the species in 1926 and 1927. In view of the amount of herpetological work that has taken place in this area, it would appear to be a rare species. Habitat and Ecology The type series was collected in forest, secondary forest, banana cultivation and bamboo. From this information, it seems that it can tolerate a degree of habitat disturbance, but probably not the complete opening of its habitat that has taken place in some parts of the Ulugurus. It is ovoviviparous, with internal fertilization, the females retaining the larvae internally in the oviduct until the birth of the toadlets. Major Threats The habitat of this species is probably being lost to agricultural encroachment, wood extraction, and expanding human settlements, especially at lower altitudes. Conservation Measures It occurs in the Uluguru North Forest Reserve, but this area is not generally managed for biodiversity conservation. Improved management of this reserve, and the protection of other remaining forest habitat in the Ulugurus, is necessary. Bibliography: Howell, K.M. (1993), Perret, J.-L. (1971a), Perret, J.-L. (1972), Poynton, J.C. (1998) Data Providers: Simon Loader, John Poynton, Kim Howell EN Nectophrynoides minutus Perret, 1972 Endangered B1ab(iii) Order, Family: Anura, Bufonidae Country Distribution: Tanzania Current Population Trend: Decreasing CITES: Appendix I Geographic Range This species is known only from the Uluguru and Rubeho Mountains in eastern Tanzania, at 1,200-1,500m asl, and probably higher. Population It appears to be a reasonably common species. Habitat and Ecology It has been found only in undisturbed forest, and appears not to tolerate habitat alteration. It is ovoviviparous, with internal fertilization and the females retaining the larvae internally in the oviduct until the toadlets are born. Major Threats Its habitat is probably being lost, especially at lower altitudes, due to agricultural encroachment, wood extraction, and expanding human settlements. Conservation Measures It occurs in the Uluguru North and Uluguru South Forest Reserves, and also in the Ukwiva Forest Reserve in the Rubeho Mountains. These forest reserves are in need of continued and strengthened management to ensure the maintenance of remaining forest habitat. Bibliography: Howell, K.M. (1993), Perret, J.-L. (1971a), Perret, J.-L. (1972), Poynton, J.C. (1998) Data Providers: Simon Loader, John Poynton, Kim Howell CR Nectophrynoides poyntoni Menegon, Salvidio and Loader, 2004 Critically Endangered B1ab(iii)+2ab(iii) Order, Family: Anura, Bufonidae Country Distribution: Tanzania Current Population Trend: Decreasing CITES: Appendix I © Michele Menegon Geographic Range This species is known only from the Mkalazi Valley at 1,200m in the Udzungwa Scarp Forest Reserve, Udzungwa Mountains, in eastern Tanzania. Surveys of other parts of the Udzungwa Forest Reserve have not located this species. Population It is reasonably common within its tiny range, though much less numerous than the sympatric Nectophrynoides tornieri. Habitat and Ecology All specimens were found in moist submontane rainforest, close to a stream. At night they can be found on leaves 60-160cm above the ground, and during the day they hide on the ground under fallen trees and coarse wood debris. Its breeding strategy is unknown, but it is assumed to be a live-bearer, like other member of its genus, with internal fertilisation, giving birth to tiny toadlets. Major Threats Its habitat is probably being lost due to agricultural encroachment, wood extraction, and expanding human settlements. Conservation Measures This species occurs in the Udzungwa Scarp Forest Reserve, but not in any well-protected areas. The population status and trends of this species require monitoring. Bibliography: Menegon, M., Salvidio, S. and Loader, S.P. (2004) Data Providers: Michele Menegon, Simon Loader EN Nectophrynoides pseudotornieri Menegon, Salvidio and Loader, 2004 Endangered B1ab(iii) Order, Family: Anura, Bufonidae Country Distribution: Tanzania Current Population Trend: Decreasing CITES: Appendix I Geographic Range This species is known only from the Uluguru North Forest Reserve on the eastern slopes of the northern part of the Uluguru Mountains, eastern Tanzania, at 1,080-1,345m asl. It appears to have a very restricted distribution. Population There is no information on the population status of this species; it is known only from two specimens, collected in 1996 and 2000. Habitat and Ecology This species is known only from tall, submontane rainforest. Its breeding biology is unknown, but it is assumed to be ovoviviparous, like other member of its genus, with internal fertilization, giving birth to tiny toadlets. Major Threats The submontane forest on the eastern slopes of the Uluguru Mountains has been extensively cleared, mainly due to agricultural encroachment, wood extraction, and expanding human settlements. Conservation Measures It occurs in the Uluguru North Forest Reserve, but this area is not generally managed for biodiversity conservation and is in need of improved management. Further survey work is needed to determine the current population status of this species. Bibliography: Menegon, M., Salvidio, S. and Loader, S.P. (2004) Data Providers: Michele Menegon, Simon Loader
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Globally Threatened Amphibian Species Part 1

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