Globally Threatened Amphibian Species Part 1

Globally Threatened Amphibian Species 237
DISCOGLOSSIDAE
VU Alytes dickhilleni Arntzen and García-París, 1995
Vulnerable B2ab(iii,iv)
Order, Family: Anura, Discoglossidae
Country Distribution: Spain
Current Population Trend: Decreasing
© Jeroen Speybroeck
Geographic Range This species is restricted to the mountains of south-eastern Spain. It occurs at altitudes of
700-2,140m asl (Sierra Nevada, Almería).
BETIC MIDWIFE TOAD
Population Populations of this species are very fragmented, many of them confined to isolated mountains and valleys.
It is relatively common in the Alcaraz, Segura, and Cazorla mountains, but it is rare in drier mountains (Filabres, Baza,
Gádor), where it is associated with springs. Populations in drier areas can consist of only a few adults.
Habitat and Ecology The species is present in pine and oak forests, most often on calciferous substrate, in open,
very rocky landscapes. Adults occur in rock fissures and on stones next to water sources. Reproduction and larval
development takes place in permanent mountain streams, man-made reservoirs and cattle troughs, and the larvae
may take a long time to mature. Almost all known breeding habitats are human-modifi ed water bodies.
Major Threats The species is threatened by loss of suitable breeding habitat as a result of excessive water
withdrawal, droughts, and modernization of agricultural practices leading to the abandonment of cattle troughs and
other man-made water sources. A potential future threat is the fungal disease chytridiomycosis, which has already
impacted the related Alytes obstetricans in Spain.
Conservation Measures This species is listed on Appendix III of the Berne Convention. It is listed in regional Red
Data Books and is present in the protected areas of Parque Nacional Sierra Morena, Parque Nacional de Sierra
Nevada, and the Natural Park of Cazorla, Segura y las Villas. Protection measures in Castilla-La Mancha, Andalusia,
such as restoration and construction of new breeding habitats, are under way.
Bibliography: Arnold, E.N. (2003), Arntzen, J.W. and García-París, M. (1995), Benavides, J. et al. (2000), Fromhage, L., Vences, M. and
Veith, M. (2004), García-Cardenete, L. et al. (2003), Gasc, J.-P. et al. (eds.) (1997), Márquez, R. and Bosch, J. (1996), Martínez-Solano, I.
et al. (2003), Martínez-Solano, I. et al. (2004), Pleguezuelos, J.M. (1997), Pleguezuelos, J.M., Márquez, R. and Lizana, M. (2002)
Data Providers: Jaime Bosch, Miguel Tejedo, Miguel Lizana,Iñigo Martínez-Solano, Alfredo Salvador, Mario García-París, Ernesto
Recuero Gil, Jan Willem Arntzen, Rafael Marquez, Carmen Diaz Paniagua
VU Alytes muletensis (Sanchiz and Adrover, 1979 “1977”)
Vulnerable D2
Order, Family: Anura, Discoglossidae
Country Distribution: Spain (Native and
Reintroduced)
Current Population Trend: Increasing
© Jeroen Speybroeck
Geographic Range This species is restricted to the Sierra Tramuntana of northern Mallorca, Balearic Islands, Spain.
The present altitudinal range is from 10-850m asl. Its area of occupancy is less than 10km², but slowly increasing as
a result of intensive conservation action.
Population The population is approximately 500-1,500 adult pairs (Gasc et al. 1997; Arnold 2003). There are approximately
25, mostly isolated, populations. The total population is slowly increasing following coordinated recovery
efforts, following a long period of decline and near extinction. The current increase, which probably started around
the time that the fi rst re-introductions were made in 1989, has been maintained even during years of drought,
notably in 1999-2000. The population trend in this species is monitored through annual tadpole counts, the counts
for 2004 (over 30,000 tadpoles) being the highest on record. The increase in numbers in established populations is
not dependent upon continued re-introductions. However, it is unlikely that new populations would be established
without re-introductions.
MALLORCAN MIDWIFE TOAD
Habitat and Ecology It is currently found only in small streams deeply carved into limestone mountains. The presence
of the species is positively associated with steep slopes. Breeding takes place in the small streams that persist
as pools in summer. A few populations occur by man-made water sources (cattle troughs, containers, rain tanks
etc.) in open mountainous country; these are within the river basins of nearby canyon-living populations. Animals
are generally found in rock crevices and under stones. This species does not tolerate serious habitat degradation.
The distribution of predators on the species is negatively associated with elevation, and reproductive success is
positively associated with elevation.
Major Threats The major threats are predation by the introduced Viperine Snake (Natrix maura), and competition
for space with Perez’s Frog (Rana perezi). Development of tourism and human settlements, specifically the increased
need for water resources (including damming and canalization of streams), is an additional threat. The threats are
not likely to decrease, and so the current recovery programme needs to be continued more or less indefinitely. One
isolated re-introduced population was impacted by an unidentified non-fungal disease in 2002 which killed some
tadpoles. This disease did not recur in 2003 and 2004.
Conservation Measures The species is protected by sub-national and national legislation. It is listed on Appendix II of
the Berne Convention, on Annexes II and IV of the EU Natural Habitats Directive, and on the national and sub-national
Red Data Books. It is present in the protected areas of the Tramuntana mountains. The Balearic Government and
Jersey Wildlife Preservation Trust have undertaken captive-breeding, re-introduction and other conservation initiatives.
At least 10 populations have been successfully reintroduced. Re-introductions of animals from the Jersey Wildlife
Preservation Trust stopped in 2002, but a new captive-breeding facility now exists on Mallorca, and re-introductions
are expected to resume. However, as a result of the recent discovery of disease, a recommendation was made in 2004
to the Balearic Government to halt the re-introduction programme. A new recovery programme for the species is now
being developed. A systematic programme is in place to remove Natrix maura from the range of the species.
Bibliography: Alcover, J.A. et al. (1984), Arnold, E.N. (2003), Arntzen, J.W. and García-París, M. (1995), Bush, S. (1996), Fromhage, L.,
Vences, M. and Veith, M. (2004), Gasc, J.-P. et al. (eds.) (1997), Halliday, T. (1992), Lea, J., Dyson, M. and Halliday, T. (2002), Martínez-
Solano, I. et al. (2004), Mejias, R. and Amengual, J. (2000), Moore, R.D., Griffiths, R.A. and Román, A. (2004), Pleguezuelos, J.M. (1997),
Pleguezuelos, J.M., Márquez, R. and Lizana, M. (2002), Roca, V. et al. (1998), Román, A. and Mayol, J. (1997), Schley, L., Griffiths, R.A.
and Román, A. (1998)
Data Providers: Joan Mayol Serra, Richard Griffi ths, Jaime Bosch, Trevor Beebee, Benedikt Schmidt, Miguel Tejedo, Miguel Lizana,
Iñigo Martínez-Solano, Alfredo Salvador, Mario García-París, Ernesto Recuero Gil, Jan Willem Arntzen
HELEOPHRYNIDAE
CR Heleophryne hewitti Boycott, 1988
HEWITT’S GHOST FROG
Critically Endangered B2ab(ii,iii,iv,v)
Order, Family: Anura, Heleophrynidae
Country Distribution: South Africa
Current Population Trend: Decreasing
© Richard Boycott
Geographic Range This species appears to be restricted to four perennial rivers (Geelhoutboom, Martin’s, Klein
and Diepkloof) with their headwaters in the Elandsberg mountains, in the Eastern Cape province, South Africa. Its
altitudinal range is 400-550m asl.
Population It is an uncommon and declining species.
Habitat and Ecology It is a species of fynbos heathland and grassy fynbos. Only very small remnants of fynbos
survive within its range, so very little non-breeding habitat survives. It breeds in fast-fl owing perennial rivers and
streams with rocky beds in the upper reaches of the Elandsberg. Adults and tadpoles are found beneath submerged
and partly submerged rocks in these streams, and occasionally at the edge of small waterfalls and cascades. The
tadpoles take two years to develop.
Major Threats The main threats are loss of suitable non-breeding and breeding habitat as a result of afforestation
with exotic pine plantations, fires, erosion, siltation of streams, dams, and road building. Introduced predatory fish
are probably also a threat.
Conservation Measures The species is not known to occur in any protected areas, and the maintenance of its
remaining breeding and non-breeding habitat is essential. There is also a need for continued monitoring of known
populations and survey work for other populations.
Bibliography: Boycott, R.C. (1988), Branch, W.R. (1988), Channing, A. (2001), Minter, L.R. et al. (2004), Passmore, N.I. and Carruthers,
V.C. (1995)
Data Providers: Leslie Minter, Alan Channing, James Harrison