Biodiversity. Confronting amphibian declines and extinctions.
7 JULY 2006VOL 313SCIENCEwww.sciencemag.org
CREDIT: RON HOLT
least 9, and perhaps 122, becoming extinct since
1980 (1). Species have disappeared across the
entire taxonomic group and in nearly all regions
of the planet. These figures are probably under-
estimates as entire clades of species are threat-
ened. For example, of the 113 species of harle-
quin toads (genus Atelopus), 30 are possibly
extinct, and only 10 have stable populations (2).
Nearly a quarter of known amphibian species
were deemed “data-deficient” with respect to
conservation status in the recent global assess-
ment (1). Losing biodiversity at this taxonomic
scale impacts ecosystem goods and services
[e.g. (3, 4)]. As amphibian species disappear, we
also losetheir untapped potential for advances in
biomedicine and biotechnology in general (5).
Losses result from familiar threats (land-use
change, commercial overexploitation, and exotic
species) and from the emerging infectious dis-
ease chytridiomycosis, caused by the fungus
Batrachochytrium dendrobatidis (Bd). Pre-
dictions are that within 4 to 6 months of Bd
arrival at a site where it has not previously been
present, ~50% of amphibian species and ~80%
of individuals may disappear (6). Global climate
change may be encouraging local conditions
ideal for Bd’s persistence and/or spread (7), com-
mercial trade of wildlife may also contribute (8),
and pollution may increase susceptibility of
species to pathogens (9, 10). Traditional pro-
grams and current laws and policies alone are
insufficient to address global threats that cross
boundaries of reserves and nations.
Global leaders in research, conservation, and
policy agreed on an Amphibian Conservation
Action Plan (ACAP) and Declaration in 2005
(see Supporting Online Material). A new, inter-
national body was recommended to coordinate
and facilitate conservation programs for amphib-
mphibian declines and extinctions are
global and rapid: 32.5% of 5743 de-
scribed species are threatened, with at
ians and to garner and administer funds. Thus,
we call for formation of The Amphibian Survival
Alliance (ASA)—led by an international secre-
tariat of the Amphibian Specialist Group of the
Species Survival Commission of IUCN (World
Conservation Union). An initial 5-year budget
requires at least U.S.$400 million.
Conservation activities should remain in
affected countries where possible, with coordi-
nation and support through ASA, to engage
and employ local scientists. A special initiative
would be regional centers for disease research
and captive breeding. Centers would exist
within government agencies, zoos, or universi-
ties and would be staffed by local scientists,
wildlife managers, and conservationists. ASA
would create and support readily available
databases from the global network of centers,
as well as research and training in countries
with few amphibian experts. Such dedicated
research capacity in affected regions is re-
quired for this global crisis, as well as to keep
amphibian research and conservation at the
forefront of policy-making.
Chytridiomycosis deserves especial attention
because of its massive impacts on amphibian
diversity (11, 12). Natural-agent control of Bdor
selecting for resistance in amphibians may be
possible (13, 14). In the meantime, we must
implement coordinated in situ actions (e.g.,
surveys, monitoring, and habitatprotection) and
ex situ husbandry programs (e.g., survival-
assurance and research colonies) at unprece-
dented scales. Amphibian salvage operations are
possible at an ecosystem level (15). Ex situ pro-
grams may be the only option to avoid extinction
for many species [e.g., Kihansi Spray Toad
and Panamanian Golden Frog (16, 17)], while
research progresses on disease control, treat-
ment, and evolution of resistance (18).
The ASA model builds on programs such
as the Turtle Survival Alliance (19), Global
Environment Facility (GEF) Coral Program
(20), and an Australian threat abatement plan
(21). Success will depend on a paradigm shift
in the scale of the coordinated response, with
stakeholders from the academic, conservation,
zoo, ethics, policy, global change, private
sector, and international biodiversity conven-
tion communities uniting for one goal. Support
from individuals, governments, foundations,
and the wider conservation community is
References and Notes
1. S. N. Stuart et al., Science 306, 1783 (2004).
2. E. La Marca et al., Biotropica 37, 190 (2005).
3. J. A. Pounds et al.,Nature 398, 611 (1999).
4. M. R. Whiles et al., Front. Ecol. 4, 27 (2006).
5. S. E. VanCompernolle et al., J. Virol. 79, 11598 (2005).
6. K. R. Lips et al., Proc. Natl. Acad. Sci. U.S.A. 103, 3165
7. J. A. Pounds et al., Nature 439, 161 (2006).
8. C. Weldon et al., Emerg. Infect. Dis. 10, 2100 (2004).
9. J. Kiesecker, Proc. Natl. Acad. Sci. U.S.A. 99, 9900
10. T. B. Hayes et al., Environ. Health Perspect. 114
(suppl. 1), 40 (2006).
11. L. Berger et al., Proc. Natl. Acad. Sci. U.S.A. 95, 9031
12. P. Daszak et al., Science 287, 443 (2000).
13. R. N. Harris et al., Ecohealth 3, 53 (2006).
14. R.W. R. Retallick et al., PLoS 2, 1 (2004).
15. J. R. Mendelson III, G. B. Rabb, WAZAProceedings, World
Association of Zoos and Aquariums, 60th Annual Meeting,
New York, 2 to 6 October 2005, in press.
16. K. Krajick, Science 311, 1230 (2006).
17. K. C. Zippel, Herpetol. Rev. 33, 11 (2002).
18. H. McCallum, Conserv. Biol. 19, 1421 (2005).
19. Turtle Survival Alliance (www.turtlesurvival.org).
20. Coral Reef Targeted Research and Capacity Building for
Management (CRTR) (www.gefcoral.org)
21. Threat abatement plans, infection of amphibians with
chytrid fungus resulting in chytridiomycosis
Supporting Online Material
Stopping further global losses of amphibian
populations and species requires an
unprecedented conservation response.
Declines and Extinctions
The Panamanian Golden Frog, Atelopus zeteki,
is nearly extinct in the wild as a combined result
of habitat change, illegal collecting, and fungal
disease; the species is currently secure in several
ex situ programs.
Joseph R. Mendelson III,* Karen R. Lips, Ronald W. Gagliardo, George B. Rabb, James P. Collins,
James E. Diffendorfer, Peter Daszak, Roberto Ibáñez D., Kevin C. Zippel, Dwight P. Lawson, Kevin
M. Wright, Simon N. Stuart, Claude Gascon, Hélio R. da Silva, Patricia A. Burrowes, Rafael L.
Joglar, Enrique La Marca, Stefan Lötters, Louis H. du Preez, Ché Weldon, Alex Hyatt, José
Vicente Rodriguez-Mahecha, Susan Hunt, Helen Robertson, Brad Lock, Christopher J.
Raxworthy, Darrel R. Frost, Robert C. Lacy, Ross A. Alford, Jonathan A. Campbell, Gabriela
Parra-Olea, Federico Bolaños, José Joaquin Calvo Domingo, Tim Halliday, James B. Murphy,
Marvalee H. Wake, Luis A. Coloma, Sergius L. Kuzmin, Mark Stanley Price, Kim M. Howell,
Michael Lau, Rohan Pethiyagoda, Michelle Boone, Michael J. Lannoo, Andrew R. Blaustein,
Andy Dobson, Richard A. Griffiths, Martha L. Crump, David B. Wake, Edmund D. Brodie Jr.
*To whom correspondence should be addressed. E-mail:
firstname.lastname@example.org. All author affiliations can be
found in the Supporting Online Material.
Published by AAAS