November 28 – The first cetaceans of the trip were recorded from the helicopter on the journey from Luanda offshore to the survey vessel.  Two groups of sperm whales were seen lying at the surface, and a vast area of white water indicated a large dolphin group on the move.  Not a bad start!  A pod of around 35 Risso’s dolphins seen ahead of the ship later in the afternoon proved initially challenging to identify, appearing suspiciously like one of the smaller blackfish species in the poor light.

November 29 – A busy day with a group of nine sperm whales observed for over an hour in the morning as they lifted their tails to embark on foraging dives.  The first of many groups of unidentified ‘Stenella / Delphinus dolphins’ were also recorded, the distance from the ship and the similarities between these small and active dolphin species precluding positive identification.  

November 29 – After a relatively quiet afternoon a splash off our port bow alerts me to a small group of around 15 animals travelling slowly between our vessel and the accompanying chase boat.  They appear to be large dolphins, with rather broad and upright fins and dark in colouration.  Unsure of their identity, I pick up my camera and take a few shots as they move sedately away from the ship.  Later analysis of the images indicates that these animals are most probably melon-headed whales or perhaps pygmy killer whales.

November 30 – The rainy season is in full flow today, with torrential rain squalls and thunder restricting visibility and churning up the sea surface.  It is mid-afternoon before the rain clears sufficiently for me to head outside and start scanning for cetaceans.  But as I scan across the horizon with my binoculars the misty vapour of a whale blow appears, shortly followed by two large triangular fins.  Killer whales!  They are milling in the area of a slick with a storm petrel zig-zagging around them, and I wonder if perhaps they have recently killed prey here.  The killers sound, and subsequently reappear several minutes later off our port bow and moving towards us.  Now that they are closer, I notice a small calf amongst them.  After one close surfacing sequence, they dive and disappear.  We look all around the ship for them for 15 min, but cannot relocate them.

December 1 – An insect invasion today!  A variety of large insects and moths fly all around the ship, presumably carried offshore by the rain clouds.

December 2 – Dorsal fins appear on the edge of the sun glare.  I can tell immediately from their tall and falcate shape that these dolphins are different to the several groups of ‘Stenella / Delphinus dolphins’ that I already recorded earlier today.  I watch them curiously as they simultaneously roll and sound, some of them lifting their tail-stocks and flukes clear of the water.  When the dolphins reappear they are only 300 m off the side of the ship, and have turned to swim alongside us.  Their bulbous heads and the visible pale colouration on some individuals readily identifies them as Risso’s dolphins.  One large animal breaches three times, landing heavily on its side with clearly audible splashes.

December 3 – A brown shape in the water catches my eye, and I raise my binoculars just in time to see the round carapace of an olive ridley turtle break the surface.  The turtle takes a few breaths, before diving deeply and disappearing from sight.

December 3 – Another turtle, and the distinctive longitudinal ridges along the carapace identify this animal as a leatherback.  The turtle rests at the surface and takes numerous breaths, passing alarmingly close to the cable that is towing some of the seismic equipment astern of us but without showing obvious reaction.

December 3 – In calm, blue seas, the splashes from leaping dolphins ahead of us are easily visible.  The animals are widely spread, and the number of splashes suggests a large group size.  I scan the area repeatedly, monitoring the whereabouts of the animals most of which appear to be at least a kilometre ahead.  And so I am caught off guard when splashes beside the bow indicate that some dolphins have sneaked in from elsewhere to bow-ride!  When I peer over the bow I can see two slender grey dolphins, and the white beak tips and speckled white flanks indicate that these are Atlantic spotted dolphins, one of the most common dolphin species in Angola.  They whistle loudly and swim circles around the bow, unimpressed by our slow speed.  As if on cue, dolphins suddenly appear from all directions.  They spend 30 minutes playing in our bow-wave, and we observe small calves, boisterous juveniles and even a mating pair.

December 3 – On my return to the observation deck after the dolphins have departed, I notice a small, colourful bird resting on the lower decks.  This is a Rufous-vented paradise flycatcher which is endemic to central Africa, and it has probably been blown so far offshore by the prevailing rainy weather systems.

December 3 – Just before dark I detect the unmistakable huge swept-back dorsal fins of pilot whales.  The group of around 25 animals includes two small calves and several enormous males, and they swim serenely across our bow before stopping and logging off the port side.  Pilot whales often seem curious about the survey vessel, and I notice one animal spy-hop as if to take a better look at us.

December 4 – The low bushy blows ahead of the ship are angled forwards and are easily identified as belonging to sperm whales.  The whales are scattered over several kilometres of water, in small sub-groups of 1 to 4 animals.  As I watch, some of the whales roll at the surface and lift their tails, commencing deep foraging dives.  Others are still surfacing from previous dives, and I estimate around 20 animals in total.  Two pass very close to our chase boat, apparently without disturbance.

December 4 – A tall and pointed dorsal fin is circling at the surface close to the ship.  The appearance of a tail fin confirms the presence of a shark, and the water surface is calm enough for me to make out the distinctive head shape of a small hammerhead shark.

December 10 – Although the splashes of leaping dolphins are difficult to distinguish amongst the numerous whitecaps, I am sure it is quite a large group that is currently playing around the bow of our chase boat.  As I watch, the dolphins begin to move in our direction, slowly at first, but then with increasing momentum as they surf the swell waves and start leaping and somersaulting out of the back of the waves.  I reach the bow before they do, and wait to see the first animals arriving where at this close range I easily identify them as Atlantic spotted dolphins.  Some of the dolphins stay to bow-ride, but the bigger attraction today seems to be the huge waves being created down our port side as the vessel rolls against the swell.  The dolphins line up in successive waves, surfing and leaping high out of the top of each wave.  For a few seconds it appears as though every single wave in the ocean contains dolphins, and then quickly they are gone, the only fin remaining belonging to a lone hammerhead shark which cruises slowly past the ship.

December 11 – Some floating debris in the water catches my attention, and I identify a large white sack!  It has become a habit for me to check such items for associating turtles, since the turtles often accompany objects in the water presumably to feed on attached invertebrates.  I am lucky this time, as a brown shape rises to the surface and the head of a turtle appears to take a quick breath of air. 

December 11 – We have been waiting for several days now to find more pilot whales in suitable weather conditions to allow a small boat trip.  I am hoping that we might be able to approach close enough to some of these animals to get good views of their flippers and flanks so that we can confirm whether the pilot whales in this area are definitely the short-finned species rather than long-finned.  It is probable that both short- and long-finned pilot whales occur off Angola, but in northern areas such as this where the water temperature exceeds 25°C it is almost certain that the tropical short-finned species predominates.  Fortunately, the crew are also keen to head out for some ‘whale-watching’ and within 15 min of my spotting some pilot whale fins we are heading out towards them in the Fast Rescue Craft.  The pilot whales are travelling slowly but purposefully and are spread out in small sub-groups.  The animals are taking fairly long dives and are initially rather difficult to approach. However, we spend 20 min moving slowly alongside them and eventually we are able to get sufficiently close to confirm the identity of these animals as the short-finned variety.  The whales lack the pale dorsal cape and eye blaze that are characteristic of some other Atlantic short-finned pilot whale populations, and instead appear uniform black in colouration.  For a few minutes we switch off our engine and drift amongst the whales, the only sound being their sharp exhalations as they break the surface.  A small unit containing a mother and calf swim slowly past us, the mother carefully keeping herself positioned between us and the youngster. 

December 11 – A strange bird is flying around the ship, its long and narrow wings looking suspiciously long for its body size.  This is certainly not a seabird, and I watch as it lands on the helideck for a rest.  The visitor is a nightjar, and this is the second time that I have seen one offshore Angola.  

December 13 – Pelagic dolphin schools in Angola are often seen ‘running’ or ‘porpoising’, travelling at high speed in smooth, shallow forward-leaps.  The group of around 50 dolphins I am watching now have been moving this way for 30 minutes, and although it looks very high-energy behaviour, it is actually considered to be one of the more energy-efficient ways for dolphins to travel.  The animals seem to be above water for only the blink of an eye, and I quit trying to identify them through binoculars and opt instead to take photographs.  The dolphins freeze-framed in my camera were later identifiable as Atlantic spotted dolphins.

December 14 – The sun glints strongly off several dorsal fins ahead of us.  These dolphins are large with very prominent falcate dorsal fins.  They also look a very brownish colour in the sunlight, and can’t be Risso’s dolphins.  I suspect bottlenose dolphins, and this is later confirmed from the photographs which show the short, stubby beak diagnostic of this species.  It is fairly unusual to see bottlenose dolphins alone in these deep waters, since they are most often seen associated with pilot whales.

December 14 – Thirty minutes ago I was fortunate enough to observe two distant beaked whales, and I am so busy scanning the horizon trying to relocate them that I almost miss the tall dorsal fins that appear a few hundred metres off our bow.  The sea and light conditions today are perfect, and there is no mistaking the bright white colouration of Risso’s dolphins which pass closely to the bow before lifting their tails and diving off our starboard side.

December 20 – The dolphins ahead of us are some of the most acrobatic I have encountered so far on the survey.  Some individuals leap repeatedly several metres into the air, hanging there for a second before dropping back onto their sides creating huge splashes that are visible for miles around.  These are striped dolphins, and I watch them for over an hour as they feed and continue to perform their acrobatics.

December 20 – It is late evening and I am watching several groups of unidentified ‘Stenella / Delphinus dolphins’ feeding around the vessel.  The mirror calm seas allow me to view some very distant animals, their backs and fins appearing as little more than small, black dots.  I am monitoring one such group, when two larger animals roll at the surface several kilometres away.  I quickly recognise the long, sloped backs and tiny triangular dorsal fins as belonging to beaked whales, but although I can make out the bow-waves from their foreheads, they are too far away to see the beaks.  The whales roll together at the surface nine times before disappearing.

December 21 – The low blows look fairly strong in the bright dawn sunlight, but I don’t think these are whales.  A brief glimpse of a tall fin amidst the swell suggested dolphins, and as the animals emerge from the sun glare, I see that they are Risso’s dolphins, surfing slowly in the swell.  This is the third group of Risso’s dolphins that has travelled past the ship today, and with a total of over 40 animals the feeding must be good for them in this area at the moment.

December 21 – I photograph a strange fin close to the ship.  The fin is tall, thin and very sickle-shaped, and appears at the surface intermittently usually out of a swell wave.  It initially took us several sightings of these fins before we worked out that they are the tail fins belonging to large billfish – marlin, sailfish and similar species.

December 22 – I have been tracking a large group of dolphins for the last hour, when sperm whale blows appear directly in front of the dolphins and right on our track line.  The whales are elusive . . . in contrast to their usual behaviour they are mostly shallow-diving and are travelling fairly long distances subsurface between consecutive surfacings.  However, they are spread out, and it quickly becomes apparent that we are going to sail through the middle of the group.  I am monitoring two whales that are logging over a kilometre off our port side, when I notice the wrinkled stationary form of a sperm whale lying at the surface only a few hundred metres ahead of the ship.  The whale eventually responds to our presence, rolling its back slightly and shallow-diving out of the way.  Another individual logging around 500 m off our port bow is clearly preparing for a deep dive, rolling its back strongly to submerge before producing one last powerful blow and lifting it’s tail into the air to disappear into the depths.

December 24 – We are in the middle of a re-fuelling operation at sea, but perhaps this just further arouses the curiosity of the pilot whales.  They swim slowly towards the bunkering vessel and pass only a few metres ahead of it.  A large male positions itself between the ship and the remainder of the whale pod.  When they get abeam of the two vessels, they stop and remain logging at the surface for several minutes, the setting sun glinting off their dorsal fins.  There is another group of pilot whales off our starboard side, and I estimate around 30 animals in total.  There are splashes from active bottlenose dolphins associated with the second group, but the pilot whales themselves appear relaxed as they rest quietly at the surface..

December 27 – An area of disturbed water near to the bow catches my eye – it looks different from the frequent small splashes produced by the tuna that swim continuously alongside our vessel.  I focus on the area and see a small brown oblong moving subsurface away from the splash.  Eventually the shape rises to the surface to take a breath, and I am able to identify a small olive ridley turtle.  On some parts of its head and carapace the turtle is covered in very bright red algae.  It takes several more breaths as it moves sedately astern of us, before disappearing from view.

December 27 – More pilot whales, this time a small pod of 10 animals that approach to within a few hundred metres of the ship.  As they turn towards the sun, the light catches the low, bushy blows produced by the larger animals as they surge through the swell waves.

December 29 – My final morning at sea this trip.  However, in stark contrast to the choppy seas earlier in the week the sea today is glassy calm!  I expect to see a lot of activity when the conditions are as favourable as this, and I am not disappointed.  The day begins with a tall, vertical blow that I easily recognise as belonging to a baleen whale of some kind.  In the calm weather I am able to photograph the back and dorsal fin and confirm this animal as almost certainly a Bryde’s whale.

December 29 – The blows that I see a few hours later are the low, angled blows diagnostic of sperm whales, and I can clearly see their backs and low dorsal humps lying at the surface like giant logs.  The whales are widely scattered and difficult to count, but I estimate at least nine animals in the group.  As I watch the two closest animals, the nearest gives the characteristic shallow roll that indicates that the next surfacing will be it’s last.  I focus my camera on them and watch as the whale produces a final blow and then rolls to lift its tail clear of the water and dive, closely followed by its companion.

December 29 – We have seen the glint of a turtle’s carapace well over a kilometre ahead of us on the vessel’s trackline.  The turtle is basking at the surface and we are hopeful of getting very close views, since they are often slow to react to the approaching ship when basking.  As the turtle gets nearer I move to the bow and can see the round shape and numerous scutes of an olive ridley turtle.  Like the turtle I saw last week, this individual has a thick covering of reddish algae on some parts of its carapace.  The turtle does not react to the ship until it is immediately under the bow, when it suddenly awakens and dives rapidly out of the way.

December 29 – More sperm whales, and this time at least 20 animals.  Most of the whales are distributed a few kilometres away along our port side, but some surface rather close off the starboard side of our ship after apparently diving underneath the survey vessel.  After surfacing, most of these close animals shallow-dive and move fairly quickly away from the vessel as if unsure about it’s proximity.  One large whale moves rapidly away beneath the water, and we can see the ‘footprints’ from the movement of its tail flukes before it surfaces again on the far side of the towed seismic equipment.

December 29 – We are so busy watching the sperm whales that we almost miss another olive ridley turtle!  The turtle appears close to the ship, and swims slowly along the surface with it’s head frequently emerging to take breaths.