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Frogs - The Global Frog Crisis
 Around
the world, the disappearance of frogs has received a great deal
of attention by scientists, government departments and the media.
Extensive monitoring programs and research projects are taking place.
We know already that not all frog species are affected by the same
causes and threats. However, in some cases, no cause for the decline
or disappearance has been identified at all. These are being called
"mystery declines". They are occurring at high altitude
locations within a particular latitudinal range around the earth.
Despite World Heritage protection, several species of frogs have
disappeared from pristine, high altitude rainforests in tropical
Queensland and elsewhere further south.
Researchers in Australia, Panama and elsewhere
have discovered a fungus which is killing frogs. This fungus has
also been found in Queensland Museum specimens collected from the
Wet Tropics uplands prior to the disappearance of the high altitude
frogs. This fungus is the species Batrochochytrium dendrobatidis
but it is usually referred to as chytrid fungus. You can learn all
about this serious amphibian disease by going through the Amphibian
Disease site created by the James Cook University researchers
who are studying this fungal menace.
What are these disappearances telling us? These
gentle animals play a role in keeping insect populations in check
and they are an important resource in the food chain, but perhaps
even more important is the sensitivity of frogs to subtle changes
in the environment. A frog's skin is protective and contains secretions
to prevent fungal infections (important for an animal that likes
to live in a wet habitat). But a frog's skin is also porous and
allows the animal to absorb water without drinking through its mouth.
This is why frogs succumb so quickly to any pollutants in the environment.
They are the first noticeable species to be affected and so, serve
as an 'early warning system', alerting us to problems that should
be examined and corrected.
Since the early 1990's, several species of north
Queensland rainforest frogs have vanished within a very short period
of time from altitudes above 300 or 400 metres. If those species
only occurred at high altitudes to begin with, then they ceased
to exist (as far as we can tell). Some species, thankfully, also
ranged below 300 metres and it is these low altitude populations
that still exist.
 The
species affected by the "mystery declines" are the:
- Northern Tinker frog (Taudactylus rheophilus)
- Sharp-snouted Day frog (T. acutirostris)
pictured right,
- Mountain Mist frog (Litoria nyakalensis),
and
- Armoured Mist frog (Litoria lorica).
Because three out of four of these have not been
seen by researchers since the early to mid 1990's, they are referred
to as the "missing frogs".
Some fantastic news was that one of the missing
frogs (the Northern Tinker frog) was rediscovered at two mountaintop
locations in late 1996. Its numbers, however, are critically low
and it is possible that we could still lose this species.
 These
four additional species have vanished from their high altitude sites
but are still found at lower elevations:
- Common Mist frog (Litoria rheocola),
- Waterfall frog (L. nannotis) pictured
at the top of this page,
- Australian Lace-lid (Nyctimystes dayi),
and
- Green-eyed Tree frog (L. genimaculata)
These four frogs are referred to as the "declining
frogs". Researchers and the community are involved in close
monitoring of all these endangered frogs as well as periodic searches
for the "missing frogs".
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