11th December 2004:  Off Los Christianos, Tenerife, Canary Islands

Logbook 13:32 UTC

“I am currently watching a mixed-species pod of short-finned pilot whales and bottlenose dolphins, in approximately 1500 m water depth between Tenerife and La Gomera islands in the Canary Islands.  I estimate between 15 and 20 dolphins and perhaps an equal number of pilot whales, and unusually they don't seem to be doing much at all.  In fact, I am still unsure whether the animals are socialising or whether they are feeding at depth - either way they seem to be lingering in a small area with much changing of direction and calm milling around interspersed with excited breaches.  The dolphins frequently break away and approach our vessel for short bursts of bow-riding, which makes me think the behaviour I am watching is more of a social nature than dedicated feeding.  What is unusual about this encounter, is that the pilot whales and dolphins are in close contact with one another and both species are fully integrated in a single school - i.e., individuals of each species are scattered within the school, rather than maintaining their own species-distinct sub-groups within the overall school as I have usually witnessed before.  I see pilot whales and dolphins surfacing together side-by-side, and on one occasion I even see a sub-adult pilot whale and a bottlenose dolphin spy-hop together - both animals were orientated vertically next to each other in the water and the blunt, bulbous head of the pilot whale broke the surface at exactly the same moment as the defined beak and slender head of a dolphin!  These kinds of coordinated and synchronous behaviours suggest to me that the two species are inter-acting with one another in quite complex ways and there is clearly communication of sorts between the species.  On many occasions I see the pale white oblong of a dolphin's belly underwater, suggesting that there is also a lot of behavioural activity going on sub-surface.  It is difficult to track the jet-black pilot whales when they are below the surface, but the coordinated surfacing of whales and dolphins together certainly implies that both species are involved in these sub-surface interactions too.  I am left pondering the nature of these interactions - the encounter certainly did not seem aggressive, more a companionable mingling of species that understood and were 'comfortable' with one another's presence". 

26th November 2004:  Start Point, South Devon, UK

Logbook 10:41 UTC

“I concentrate intensely through my telescope which is focused on a small slick of water between some partially submerged rocks and the choppy edge of the fierce tidal rip that prevails around Start Point headland.  The white gannets circling in the area are peering down into the water equally intensely, waiting for some unknown signal.  Suddenly the gannets fold their wings and plunge dive into the water, and at the same time I see the tiny backs and fins of 5 or 6 harbour porpoises surface rush rapidly in the same area.  The porpoises and gannets have been feeding fairly solidly since I arrived here an hour ago.  Although there are porpoises scattered all over the wider area in small groups, the dots on my map indicate that there have been more sightings in this area adjacent to the tidal rip than chance alone could dictate.  I suspect that the porpoises are using both the physical presence of the rocks and the effective oceanographic barricade of the faster, turbid water within the tidal rip as barriers against which to trap fish.  Occasionally the porpoises enter the rip itself and swim rapidly in the same direction as the breaking waves, almost surfing at times.  I haven’t figured out the purpose of this behaviour, but the gannets clearly understand its function and track the porpoises keenly".

16th October 2004:  Angola, West Africa, Seismic survey vessel

Logbook 09:00 UTC

“I gloomily scrutinise the unfavourable combination of a south-westerly force 5 wind, numerous large breaking whitecaps, and a 40 degree sea surface covering of harsh bright sun glare.  This is not the kind of weather that I usually associate with Angola!  It is the fourth day of my six-week shift and so far I have had only three cetacean sightings in these continuous adverse conditions.  But with the seismic airguns due to start firing within the hour, I am nevertheless patrolling the helideck in a seemingly futile search for cetaceans and turtles. 

However, gazing out towards the sun glare I am surprised to see a large splash just over a kilometre off our port bow.  Thankful for my polarised sunglasses, I lift my binoculars and scan the edge of the sun glare – my field of view is instantly filled with the silhouetted backs and falcate dorsal fins of porpoising dolphins.  And they are porpoising towards me!  I am a little shocked by this turn of events!  Not only had I expected to see absolutely nothing in this weather, but in the entire 11 weeks that this survey has been running we have had only one group of dolphins that approached the vessel to bow-ride.  Hardly daring to hope, I grab my radio, clipboard and camera and head to the bow.  The dolphins are there before me – I arrive and peer over the railings to see four dolphins sedately rolling on their sides and looking back up at the high bow of our ship.  They have a sprinkling of white spots along their flanks -  I register this descriptive information, and simultaneously radio the Instrument Room to let the crew know that there are dolphins around the ship.  Yes, they have spots but they don’t have the defined dark cape of Pantropical spotted dolphins.  Instead, there is a forward-projecting dark dorsal blaze along their shoulders, and I now know that these are the closely related Atlantic spotted dolphins.  And there are many of them – waves of dolphins are approaching from the front of the vessel, and yet more are porpoising in long athletic leaps alongside the ship – probably 400 or so in total.  The dolphins amuse themselves playing on the bow wave, surfing alongside the ship and leaping high from the waves and belly-flopping down to create giant splashes.  There is apparently some system at work here – the 400 dolphins cannot all ride the bow wave at once, but they seem to stagger their approach so that everyone gets a turn.  Fanciful perhaps, but at most there are only 30 or so dolphins on the bow at any one time despite the steady approach of more and more dolphins from ahead of us!  After 20 minutes the dolphins tire of the rather limited bow-wave that our 4 knot speed can offer them, and in an impressive tightly-bunched porpoising school they rapidly move off".

14th July 2004:  Isle of Coll, West Scotland, UK, Research vessel

Logbook 06:37 UTC

“I am on the bridge clutching a cup of coffee as our vessel departs the Isle of Coll and turns south-west along the coast towards Gunna Sound, after which we will commence our official survey transect work.  Casually scanning the smooth sea surface, my eyes are caught by a tall black shape that appears from the water several kilometres away and then slowly sinks back beneath the waves.  It takes a couple of seconds delay before my instinct kicks in – there is only one thing that the shape could have been, and I turn back and focus attentively on the location.  If I see the shape a second time then I will know for sure, and be running and screaming for the rest of the team.  My stomach leaps as the shape reappears.  I dash down the two flights of stairs, grab my binoculars and shout at the top of my lungs ‘killer whales!’  As we assemble excitedly on deck and scan out towards the distant Treshnish Islands, the tall unmistakable dorsal fin of an adult male killer whale appears again.  Through the binoculars I can now make out an animal with a smaller dorsal fin behind the male – perhaps a female or an immature animal. The pair of killers make their way slowly northwards towards Mull, the giant dorsal fin of the male cutting ominously through the grey sea like a knife.  I can hardly believe my luck – despite a week of dedicated scanning during the research transects, it is a casual sighting over a cup of morning coffee that proves most rewarding!”

29th June 2004:  West of Barra Head, Outer Hebrides, UK, Research vessel

Logbook 16:55 UTC

“I try and lift my binoculars for another scan, but yet again the combination of swell and strong wind beats me as the vessel lurches to the side and I am forced to lower my binoculars and grab a side rail.  This weather was not unexpected - we are west of the Outer Hebrides facing the open waters of the North-east Atlantic and the ever-present challenge of the weather is yet again hampering our survey efforts.  Wryly, I accept the challenge and try again.  This time, a tall misty blow appears briefly in my field of view.  I immediately pick up my radio and call the port-side team – ‘blow, somewhere over here!’.  They laugh at my vagueness, but I can’t be any more specific – the blow was seen only for a split second as the momentum of the ship rolling threw myself and my binoculars in a warp-speed scan across the entire starboard quarter!  Somewhere out in the churning greyness was a whale, but I have no idea exactly where.  I dash to the bridge and write down the time and GPS position before heading back to try and relocate the whale.  To my surprise, my next scan reveals not the large back of a rolling whale, but a couple of tall and falcate dorsal fins.  I am instantly aware of my mistake – the blows of some of the larger odontocetes are often visible in this kind of weather, and as the animals surface again the combination of tall, wispy blows, prominent dorsal fins and silvery colouration reveals these to be Risso’s dolphins and not the humpback whale I had been hopefully imagining!  To our delight, the Risso’s approach the vessel to check us out – their white colouration makes them easy to track under the water at close range and I watch one of the animals roll on its side a few metres away and look up at the ship before peeling away, rejoining its two companions and disappearing back into the greyness”.  

15th April 2004:  Gabon, West Africa, Seismic survey vessel

Logbook 12:43 UTC

"Scanning the water ahead of the survey ship, I notice another large flock of sooty terns feeding a few kilometres ahead of us.  As I watch, I detect a few low, bushy blows at the surface followed by some large, black dorsal fins.  A pod of pilot whales are making their way towards us, and they are not alone - a closer look reveals several smaller animals with sickle-shaped dorsal fins, and I suspect this is another mixed pod of pilot whales and bottlenose dolphins.  The seismic airguns are currently operating at full volume and I watch with interest to see how these animals will react.  Pilot whales are notorious amongst the MMOs for consistently approaching close to seismic vessels and I have already had close encounters with several groups in Angolan waters.  The dolphins veer off towards the chase boat which is currently about 2 km ahead of the main seismic vessel, and I watch as they porpoise towards the vessel and bow-ride for a short while.  I am able to confirm their identification as bottlenose dolphins from their uniform colouration and short stubby beaks.  The pilot whales are split into three sub-groups, and are travelling steadily down the starboard side - the first group of three whales does not come closer than 1 km and I track them clear of the ship.  The second sub-group contains a small calf, and they travel in a tightly packed group down the side of the vessel at about 500 m distance.  I leave the bridge and head down to the helideck at the stern of the ship to better determine how the whales will react to the towed airguns.  The whales travel parallel to the guns but then suddenly make a sharp turn to their right and travel directly acoss the stern wake of the ship (presumably underneath the seismic cable) and within 500 m of the firing airguns.  I watch the young calf stop behind the guns and spy-hop, lifting its head clear of the water, apparently to examine the vessel?  I wonder why the whales are so determined to reach the port side, and as I turn to look I notice the bottlenose dolphins have left the chase boat and are travelling in scattered groups down the port side with occasional breaches.  I am so busy watching the pilot whales and the dolphins reforming a group on the port side, that I almost miss the third pilot whale sub-group!  However, a tail emerging from the water less than 250 m off the bow alerts me to their presence, and I dash from the helideck to the bow to try and track their movements past the ship.  The sub-group contains a large male, a juvenile and two other animals.  Unbelievably, they appear to be socialising next to the seismic ship - I watch them log at the surface and repeatedly lift their tails clear of the water in a slow and gentle movement that is very much different from the rigorous tail-slapping one sometimes sees in this species.  The male rolls on his side and lifts his pectoral fins clear of the water and I am able to confirm that these are short-finned rather than long-finned pilot whales.  The group remain almost stationary at the surface as the vessel passes by, and then turn and travel slowly alongside the ship for a short while.  Finally they move off astern of us (passing within 200 m of the airguns), in the direction of the other animals".

Pilot whales and bottlenose dolphins frequently associate, and I have seen several such mixed-species groups this trip.  However, I have noticed that bottlenose dolphins consistently keep further away from the seismic ship than the pilot whales, and that the latter species frequently appear to actively approach within 1 km of the firing airguns.  As with so much cetacean-behaviour, my observations of pilot whales during this survey have raised more questions than answers!

17th January 2004:  Gulf of Mexico, U.S., Seismic survey vessel

Logbook 14:53 UTC

"Seismic operations are currently postponed due to rough weather - there is a 2.5 m swell and plenty of whitecaps, certainly not ideal weather for detecting cetaceans.  However, our eyes are still drawn to the waves in search of dorsal fins.  As I chat to the Captain, a dark shape emerges from a wave and ploughs towards the ship.  I quickly make my way to the bow and soon locate a dark shape travelling slowly alongside the ship under the water. The animal surfaces at the bow to reveal a 5 m-long dark slender and torpedo-like body with a rounded head and falcate dorsal fin.  False killer whales!  

The first whale swam laboriously around the bow and was soon joined by four other animals including a small calf.  Several of the animals exhibited tiny round scars along their dorsal surface, and the first whale had a small piece of skin peeling backwards on its flank to reveal pink blubber beneath. Perhaps the most surprising aspect of the encounter was the continuous frenzied whistling from the whales, which was clearly audible to me above the water. After five minutes the animals tired of our sedate speed and headed off north-east into deeper water. A brief but rewarding encounter."

6th November 2003:    Point Lynas, Anglesey, UK.

Logbook 10:20-12:25 GMT

" . . . Walking to the lighthouse I immediately noticed 50+ gannets circling close to shore and plunging at speed into the water in pursuit of fish.  Such congregations of feeding gannets almost guarantee cetacean activity, and I was not disappointed - a small pod of five harbour porpoises surfaced under the nearest gannets, and close enough to clearly hear the sharp blows as they surfaced to breathe.  Such sharp inhalations of breath have earned porpoises the nickname of 'puffing pigs' in Scotland!  Scanning the waters around Point Lynas with binoculars, I estimated a total of 30+ porpoises feeding in scattered groups in the tidal rips and out to the horizon, most groups accompanied by gannet escorts.  Several groups remained within 300 m of the headland and provided me with some of the best views of porpoises I have experienced in nine years of sea-watching!  Quite contrary to any identification guide you will read, porpoises near Anglesey are exceptionally active aerially, and breaching clear of the water in 'dolphin-style leaps' is not unusual behaviour.  Porpoises tended to surface in glassy slicks amongst the tidal rips, and several animals appeared to feed together in almost coordinated activity seemingly herding shoaling fish.  The breaching behaviour tended to occur as several animals congregated together.  Coordinated surface-rushing was also exhibited several times, with porpoises moving rapidly through the water producing spray and large splashes.  Unusually, the tail flukes were seen twice when porpoises sounded - clearly they were diving relatively deeply, and it is possible that they were at times foraging on the seabed . . . "

Although the harbour porpoise is typically reported as an undemonstrative species, these observations made continually over a two hour period suggest that at times the harbour porpoise can be just as energetic as its larger dolphin relatives.