Strangers in the night
Most of the creatures you are likely to encounter look almost nothing like their adult forms , and some of them you may never even have heard of . Pteropods are free-swimming pelagic sea slugs and sea snails . You may see them during the day but at night they are much more noticeable . A diverse group of molluscs , they are present in every ocean , and encompass both sea butterflies and sea angels .
Crustaceans such as larval shrimp , crabs and lobsters can often be seen in various stages of their complex lifecycle , the crab megalopa looking nothing like its adult form , and lobsters which are completely transparent .
Salps can be home to a number of different organisms , often several species on one chain . A salp is a barrel-shaped planktonic tunicate that forms long chains which move around the water column by pumping water through their structure . It is possible to see amphipods , fish and other species living in and around these jelly-like creatures . The argonaut is a pelagic species of octopus and is a bit of a superstar of blackwater diving . They are tiny , the males growing up to only about 2cm , although the ones we encountered were often much smaller . The female constructs a thin shell in which to brood her eggs , and it is this shell which gives rise to their nickname of paper nautilus .
Other cephalopods you may encounter include squid and various octopus species . Abralia , bigeye reef squid and diamond squid are all coveted species for underwater photographers , however they are generally fairly tricky to photograph , as they actively swim away to avoid the light . The pelagic blanket octopus is another target species , spending their entire life in the open ocean . They can grow rather large , the females reaching up to 2m in
“ I found a subject I ’ d never seen before on every dive ”
Alien form of a larval anemone
UKDIVING
A juvenile wunderpus on Pash ’ s first blackwater dive length , and get their name from a blanketlike structure that they can unfurl and retract .
Possibly the most sought-after subject though is the aptly named Wunderpus photogenicus . This alien-like larval octopus has a bulbous transparent head , and long arms , with hints of the colour pigments and chromatophores it will possess as an adult . The wunderpus seems calm when photographed , and does not attempt to evade the light like some other species ,
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