Page 67 - BBC Wildlife Volume 36 #12

Known as everything from
tanislav, our guide to Postojna
Cave, reassures us: “I'll only
turn the lights off for a minute
or so.” Still, it’s a shock when
we are plunged into pitch-black.
My eyes strain to pick up even
Sthe faintest hint of light, but
there is none. We were warned it might be a
bit overwhelming, and I’m starting to feel a
little disorientated. The only thing I can hear
is the quiet breathing of those with me, and
the only thing I can feel is the cool metal rail
that I’m gripping to steady myself.
I feel completely inadequate in terms of
being adapted for the dark, and it’s bizarre to
think that anything could live in this kind of
environment, but Stanislav assures me that
there are over 100 species found in this cave
system, including a ‘dragon’.
Postojna Cave is world-famous and is
located in Slovenian’s karst region – a
limestone plateau that stretches from
southwest Slovenia to northeast Italy. The
cave was carved by the Pivka River across
millions of years, and many parts of the
cave system are still flooded. Graffiti dating
to 1213 shows that the caves have been used
'baby dragon' to 'human
fish' the olm continues
to reveal new surprises
for those studying this Wild Wonders of Europe/Hodalic/NPL
cave-dwelling salamander.
by humans for centuries. The system is
over 24km long, with at least four caves,
connected by the river, and home to a variety
of breathtaking rock formations, and to the
secretive ‘dragons’.
But forget about any images you might
have of fire-breathing beasts. The ‘dragons’
in question are actually olms, cave-dwelling
salamanders, which have been surrounded
by mystery for centuries. Local people often
saw the olms after heavy rains washed them
from the caves, and believed they were the
offspring of 'cave dragons'. With the olm's
sinuous body and external gills, it’s not too
difficult to understand this particular case
of mistaken identity.
Adapting to the dark
Unlike the majority of amphibians, the olm
is completely aquatic, and like all troglobites
(true cave-dwelling creatures), it is adapted
to living its whole life in the darkness of
caves. It lacks any pigmentation in its skin,
resulting in it being a pink or yellow-white
colour. This led to it being described as a
‘human fish’ by locals, due to the similarity
of its coloration to their own skin colour.