The bridge itself was an occasional haven and refuge from the falling temperatures on the wing ...
More Sooty Shearwaters passed by but in ever diminishing numbers ...
A Southern Giant Petrel came close by showing the greenish tip to the bill ...
... and Cape Petrels toyed with the disrupted winds around the ship ...
Ahead of us lay the fabled Antarctic Convergence where the sea temperature drops by around 5 deg C and creates upwelling which in turn produces the conditions favourable for producing an increase in plankton and so ... birds.
The other factor that we were constantly aware of was water depth ... were we over the continental shelf ? Were we approaching an ocean ridge created by a subduction zone resulting from tectonic plate activity where the sea was no longer 3,000 m deep but maybe 300 m deep ? This might again produce more available food and perhaps be associated with cetacean activity which in turn could have potential benefits for seabird activity. A visit to the bridge would always provide the information relating to sea temperature and water depth from the sophisticated instrumentation there.
Our first Light-mantled Sooty Albatross appeared - a species of astounding elegance and with wonderfully subtle velvety colour tones ...
... we would have more encounters with these birds on their breeding grounds ...
A juvenile Black-browed Albatross made a rare appearance - almost all individuals of this species that we saw were adult birds. The darkish underwing and dark tip to the otherwise light grey bill showed well ...
Another juvenile albatross came by ... this time a Grey-headed Albatross and another new species for me ...
... a very distinctive bird following on from the very many Black-broweds we had seen ...
... and sharing a similar underwing pattern.
Now that we were in the cold water zone the predominant prion was Antarctic Prion , with its darker head pattern, more extensive black on the tail tip and broader based more robust bill ...
... we would encounter feeding flocks of these from time to time ...
The great albatrosses of the genus diomedea never fail to impress with their 2.5 - 3.5 m wingspan and this Wandering Albatross made several wide circles around the ship. This is another species associated with the cold water zone and less closely tied to the continental shelf than Southern Royal Albatross, the other member of the genus diomedea that we had become so familiar with. This individual, in probably stage 3 plumage was still far from being adult ...
Another Southern Giant Petrel was on the sea. This was a darker , younger bird but showed its greenish bill tip ...
... as it took off from the water.
Another cold water species that we began to encounter was Black-bellied Storm-Petrel which became quite common ...
Through the mist the Shag Rocks became perceptible and heralded our approach to South Georgia ...
... and gave a taste of the stark landscape which lay ahead.
A South Georgia Cormorant flew right overhead ...
A Northern Giant Petrel , now increasingly scarce as we headed south, put in an appearance showing its reddish tipped bill ...
... and small groups of 'porpoising' King Penguins made their way across the ocean ...
... and gave a taste of what lay in store ...
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