Page 70 - BBC Wildlife Volume 36 #12

OLMS

Brought to life

In2016,fortheirsttimeinPostojna’shistory,
scientistsandthepublicwitnessedafemale
olm laying her eggs in an aquarium.

IN ISOLATION
The mother
fiercely protected
her first egg
from the other
olms in the tank,
prompting the
scientists to
relocate them to a separate tank – easier to
relocate them than the anxious female.
Infrared cameras were installed in the tank.

ON THE
ROCKS
For two months,
the female laid a
total of 64 eggs
– the majority on
The latest indings show The sections of the underside of
a rock. Scientists
Postojna Cave
that the olm has the that are open didn’t know what would happen next –
to the public
are beautifully would all the eggs be fertilised? Would they
extraordinary ability lit to highlight succumb to tiny water predators or fungi?
the sculptural
to regenerate lost limbs. formations. MOVING ON
The 22 remaining
eggs that
showed signs
‘just’ a high school biology teacher at the Like the olm, the cave loaches are of embryonic
time and I had my hands on the world’s adapted to their life in the dark. Compared development
most exciting crustacean!” to their surface-dwelling relatives, they were moved
Alongside their adaptations for have very pale skin which lacks scales, and into a special
underwater cave life, remipedes have they have reduced eyes. laboratory.As 11 eggs had fallen of the
another unique feature, as Boxshall Since the discovery of the cave loach, rock, the scientists attached these to a
explains. “They are the world’s only researchers have been studying it closely special metal mesh with drilled holes.
venomous crustaceans. They hunt for and have managed to breed it in captivity
shrimp through the water column in and sequence its genome. LITTLE
flooded caves and then kill using their Keeping troglobites in captivity provides LARVA
venom-filled fangs. I think they are the scientists with the perfect opportunity to Four months
most fascinating cave creatures.” To study these fascinating creatures and new, after the first egg
date, remipedes have been found in the surprising discoveries continue to come was laid, a baby
Caribbean, Western Australia and the to light through this research. In fact, the olm hatched.
Canary Islands but, hidden away as they latest findings from Postojna Cave show The remaining 21
are, who knows where else they could be. that the olm has the extraordinary ability larvae hatched
to regenerate lost limbs. over the next 45 days. Unlike the adults,
Further study As I leave the caves behind and emerge olm larvae have eyes, pigmented skin and
Scientists are still finding new, surprisingly back into the daylight, I find myself just one pair of legs when they first hatch.
large, troglobite species. Until recently, thinking of the wide range of creatures that
the olm was thought to be Europe’s only call the caves home, and I start to wonder GROWING UP
vertebrate troglobite. However, in August what will be discovered next. After two months,
2015, cave diver Joachim Kreiselmaier the larvae had
spotted and photographed cave fish MEGAN SHERSBY is the Editorial developed their
during a dive in the Danube-Aach system Assistant of BBC Wildlife Magazine. hind legs.At four Cave: Alex Hyde/NPL; life cycle: Postojna Cave Park
in southern Germany. Between this She visited Postojna Caves with the months, they
initial sighting and 15 further dives until Slovenian Tourist Board: www.slovenia.info entered their
November 2016, Kreiselmaier and other juvenile phase.
divers were able to net and bring back five FIND OUT MORE Visit the Life in the Dark It's thought they stay in this phase for 14
live loach specimens for scientists to study. exhibition at NHM: bit.ly/nhmlifeindark years, growing slowly.Their eyes become
covered in skin within two or three years.
70 BBC Wildlife