Amphibian pathogens and diseases
Dr Pete Minting
Scottish Project Officer
Amphibian and Reptile Conservation (ARC)
Global declines in amphibian populations
• Houlahan et al 2005 Nature
• First major decline in the 1960s
Amphibian pathogens and diseases
• Not all pathogens cause disease!
• Amphibian chytrids – Bd and Bs
• Ranaviruses
• Ranid herpesvirus
• Amphibiocystidium
• Probably many others…
Bd Batrachochytrium dendrobatidis
• Global impact; many amphibians can be infected
• Some species resistant or tolerant
Bd lifecycle
From L. Berger, 2005
A – motile, aquatic zoospore
B – zoospore encysts in skin
C – developing zoosporangium
D – monocentric zoosporangium
E – colonial thallus – ejects zoospores
J. Brunner
Bs - Batrachochytrium salamandrivorans
• Similar to Bd
• Sometimes visible
• Martel et al 2013
• Effect on UK newts?
Fire salamander with Bs lesions
© An Martel, University of Ghent
Ranaviruses
•
Price et al. 2014 Curr Biol
Ranid herpesvirus
• Ranid herpesvirus 2 found in UK
• Common frogs Rana temporaria
• Lesions look like candle-wax…
• Population effects unknown
Dermocystid ‘Amphibiocystidium’
• Several species susceptible
• Including palmate newt Lissotriton helveticus
• Conservation significance largely unknown
• Studies in progress…
© Jelger Herder
What else is out there?
Chytrid Blinders: What Other Disease Risks to
Amphibians Are We Missing?
Duffus, Amanda L; J. EcoHealth6.3 (Sep 2009):
335-9.
• Self-referential bias in Bd research
• Some good science, some not…
Can amphibians evolve to cope with pathogens?
• Resistance
• Tolerance
• Extinction?
What can we do about amphibian disease?
• Control amphibian trade more effectively
• Schlaepfer et al (2005) – trade is huge!
• Take biosecurity precautions
• Reports of disease can help inform research
• www.gardenwildlifehealth.org
• What do you think an ‘Advice Note’ should say?
Amphibian pathogens and diseases
Thanks for
listening!
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