Operation Iceberg diary: Pond at the Top of the World
"Operation Iceberg" is a five-week mission for our team of scientists and filmmakers to document the life-cycle of Arctic icebergs from their birth to death, hoping to reveal their secrets in a BBC/Discovery Channel co-production. This is the fourth of my BBC Nature diaries, detailing my investigation of the life lurking in a polar pool.
Floating above our camp on a small plateau lies a pond mirroring the giant Store glacier in its still cool water.
It is clear and shallow. Its bed is clothed in amber coloured algae which enhances its apparent warmth, although the brilliant overhead sun makes it tolerable for bathing, washing socks and for life to flourish. Not a great variety of life, but life nevertheless.
There may well be many species of algae but only four are big enough and discernibly different to my untrained eyes.
One forms in long kelp-like ribbons which lie unrolled across the bottom, its fronds reaching some ten to fifteen centimetres in breadth.
There are three types of larger aquatic plants, the most obvious looking much like a "horsetail" with its tasselled tips reaching clear of the water.
In places the verdant mosses which form the soft shores float in a thick algal/moss soup which clogs the shallows.
I wandered the shore for over an hour and turned a few stones in search of animal life. I found just four species.
One was some sort of water flea-like daphnia - too small to catch and thus a mystery.
A treat was to spot a species of fairy shrimp. It is a relatively rare freshwater creature in the UK, one I have only seen before in a New Forest pond and in the deep water-filled ruts made by tanks on Salisbury Plain.
They are inhabitants of temporary ponds that dry out completely in the summer. They survive these dry times by producing thousands of eggs earlier in the year which lie dormant until next year's rains refill the sandy scrapes.
Here of course these periods of dormancy will get them through extended periods of freezing, as this too is very much a seasonal pool.
Fairy shrimps are filter feeders and characteristically swim horizontally on their backs with their many appendages both propelling and sieving the water as they buzz slowly along.
In a tank they are particularly beautiful as spectra form tiny rainbows in their wafting limbs.
Most obvious however is a species of diving beetle and its larvae.
The adults are black and just over a centimetre from head to tail end. They swim with the typically erratic beat of their kind, often carrying a silvery bubble of air on the tips of their abdomens.
The larvae are double their length and armed with large predatory mandibles. I fished one out for a photo and it immediately began nipping my palm.
Not surprisingly I didn't see a single mosquito larvae in the pond - given the abundance of these little beetle assassins and their ferocious and furtive activity they wouldn't last long.
But how do these beetles survive the frozen months here?
Well, the adults can fly so they in theory could be migratory, only arriving after the melt. I imagine this is unlikely on account of the distances and the short season.
Thus they must over-winter in some part of their life cycle, egg, larvae or adult. Eggs may be the most durable but if the larvae need to grow over several seasons in these cool and relatively unproductive waters then they must have a survival mechanism to get them through the pool's annual ice-age.
All of this water body will be solid ice for a minimum of eight months. I suppose they must have forms of 'anti-freeze' in their bodies, or some other capacity to protect their cell structures from ice crystal damage, both adaptations seen in invertebrates.
There is also one other much smaller beetle species whizzing about in the pool.
When I glance up from my pond dipping out over the void to the glacier just a few kilometres away, I am moved to admire the audacity and tenacity of this sparse but brave assemblage of species eking a profitable existence on the very edge of possibility.