Some of our field notes from the 2006 field season are archived here:

November-December 2006:  Angola, Southern Africa, Seismic survey vessel

Please visit our December Diary page for details of the highlights and field notes from survey work carried out in Angola during November and December, including sperm and pilot whales, dolphins and turtles.

November 4 2006: Research survey vessel, Aberdeen, North-east Scotland  

Logbook 14:45 UTC 

"Another day . . . another encounter with the bottlenose dolphin with the spinal deformity. The dolphins are feeding and are widely dispersed as individuals or in small groups scattered around the waters off Aberdeen harbour mouth, and we are able to observe the behaviour of the deformed animal when it is travelling at its own pace rather than trying to keep up with the rest of the group. The arrival of our boat is greeted enthusiastically by another juvenile, this one looking fit and healthy and ready to play! The animal swims at our bow and leaps alongside as we head slowly over to where the deformed youngster is slowly milling. Its surfacing behaviour is quite unlike that of a healthy bottlenose dolphin, with the body so distorted that sometimes the entire length of the animal lies across the surface before it sounds. Frequently the tail stock and flukes are lifted, and it seems that the animal is not sufficiently supple to roll smoothly at the surface like a 'normal' dolphin. 

With its bent-over dorsal fin and long, lumpy body shape, the dolphin presents a bizarre profile when it surfaces, and the apparent extra effort required to swim and breathe has everyone on the boat feeling concerned and sympathetic. The healthy juvenile continues to cavort around our vessel, and we can see footprints from the deformed animal that shows it is also heading towards us. Briefly we see the dolphin underwater as it arrives at the boat and twists over to look up at the bow before it disappears into the murky water below, presumably unable to bow-ride actively like its colleague. As we stop the boat and drift for a while, the two youngsters surface close together and right beside us, the comparative difference in their dorsal profiles clear to see. For several minutes they swim around and underneath our drifting boat, clearly interested in us. 

Unfortunately the late wintry afternoon in Aberdeen is dark and overcast and consequently very poor for photography, which is a pity given the excellent encounter we are having. The deformed and the healthy youngster are about the same size and are clearly well-associated, surfacing simultaneously side-by-side and turning together in synchrony. However, time is against us, and with nightfall imminent we reluctantly turn our boat away from the dolphins and head slowly southwards back towards Stonehaven".

November 3 2006: Research survey vessel, Aberdeen, North-east Scotland  

Logbook 13:16 UTC 

"Ahead of the boat a tall, powerful blow appears backlit by the winter sun and we audibly hear the exhalation from a surfacing cetacean. The blow lingers for several seconds before dispersing, and we stare in amazement. For it is not a fin or a humpback whale that we are encountering, or even one of the large dolphin species such as a killer whale. These are bottlenose dolphins, and we have never before seen one produce such an enormous whale-like blow! Several smaller blows appear around it, and we turn the boat around to travel back up the coast with them and try to take some photo-identification shots. We have already encountered this group two hours ago, while they were feeding further south. Now they are transiting slowly up the coast towards Aberdeen, and seem relaxed enough to allow our boat to travel alongside for a while. The group contains several strange-looking animals, including an adult whose skin is heavily mottled with skin lesions, and a young animal with a spinal deformity. 

We are still not sure whether the latter is the same individual that we encountered during a previous survey off Aberdeen in June (see note from 2 June 2006), or whether it is a different animal with a similar deformity. So we concentrate on photographing both the deformed dolphin and the dorsal fins of the associated adults, in an effort to try and match individuals between the two sightings. 

Later analysis of the photographs should hopefully reveal whether this is the same group of dolphins that we photographed in June and provide indication of the progress of this deformed youngster".

August 21 2006: Seismic vessel, Moray Firth, North-east Scotland 

Logbook 12:13 UTC 

"Whitecaps dominate the sea surface, but nevertheless I am pretty certain that it was a splash that I just saw a few kilometres ahead of the ship. Straining through my binoculars I scan the area and wait for further signs. And sure enough, a distinctive burst of spray appears amongst the white horses. Dolphins! But which species? We are in the Moray Firth, an area world-famous for its resident population of bottlenose dolphins. Yet the bottlenose dolphin population typically remains within a kilometre of the coastline while we are about nine miles off Kinnaird Head near Fraserburgh. Moreover, the dolphins I am watching look small, slim and agile compared with bottlenose dolphins. The animals are possibly feeding, with some high leaps and splashes visible. I already suspect that these may be common dolphins which have been reported in this area on several occasions during the summer, but they are simply too far away to identify properly at this range. I am resigned to logging them simply as 'unidentified dolphin sp.', when the bosun offers to make me out in the fast rescue boat for a closer look . . . Fifteen minutes later, and we are ploughing our way through the swell waves away from the seismic ship, and out towards where we think the dolphin group might be. Common dolphins are usually very boat-friendly animals, and if my suspicions about the species identification are correct then I expect them to be easy to find. After only a few minutes of searching, dorsal fins appear off the starboard side and heading straight towards us! 

Some of the dolphins swim immediately to the front of the ship to ride the bow-wave, while others surf in the stern wake and leap alongside. With these close views I can clearly see the prominent beaks and beautiful hourglass flank markings that confirm their identification as short-beaked common dolphins. 

The dolphins are very vocal, with those at the bow emitting loud whistles that are clearly audible to us inside the boat. We notice several very small calves amongst the 40-strong group, each one approaching to bow-ride alongside the adult animals. After ten minutes photographing the dolphins we leave and head back to the seismic ship, the mystery of their identification now pleasingly solved!".

August 20 2006: Seismic vessel, Moray Firth, North-east Scotland 

Logbook 06:38 UTC 

"The glassy seas in the Moray Firth today are perfect for spotting the UK's smallest cetacean species, the harbour porpoise. Tiny (5-6 ft) in size and elusive in behaviour, these animals are extremely difficult to spot unless conditions are mirror calm, with studies showing that their sighting rate decreases markedly even in Beaufort sea state 2. In the two hours that I have been on watch this morning, I have already seen three porpoise groups including a mother-calf pair. Now we are on the run-in to another seismic line and I am carefully monitoring 360° around the airgun array to ensure that no marine mammals are in close proximity to the guns prior to operation. I am walking back around the helideck to check the port side, when out of the corner of my eye I note a small dark shape roll quickly off the starboard side. Porpoises have a distinctive quick motion at the surface, and I am already positive that the shape will turn out to be this species.

 However, I wait for visual confirmation before radioing the acoustic monitoring team, since the animal is clearly within the 500 m exclusion zone around the airguns and will require mitigating action. A second or two later, and the small back and triangular dorsal fin of a single adult porpoise appear at the surface again, and I immediately radio the crew to request that airgun use should be delayed for at least 20 min until the animal has cleared the area. In the meantime, I photograph the porpoise for our records, and continue to track it as it travels astern of the vessel and away from the airguns. Although tempting to continue to watch this porpoise, as soon as it has left the 500 m zone I return to scanning 360° around the airgun array to check for other marine mammals in case further delays to seismic operations are necessitated". 

July 5 2006: Seismic vessel, Rockall Trough, North-west Scotland 

Logbook 08:52 UTC 

"A tall, vertical blow is just visible against the foggy horizon. The blow is one of a sequence of five, after which the animal, presumably a baleen whale, sounds and travels subsurface for a while. At this range we still have not seen the whale itself, as its body remains hidden in the swell with only the tell-tale blow giving away its location. Unsure where it will next surface we keep a good look out all around the ship. Five minutes later, two strong blows appear simultaneously and we realise there are two animals travelling together towards the ship. A long sloped back briefly appears high in the swell, and as the animal rolls and sounds I clearly see the prominent sloped dorsal fin indicative of a fin whale. Judging by the distance travelled in the last two surfacing sequences, we are expecting these animals to next surface relatively close to the ship. I move up to the bridge roof from where I can scan 360° around the vessel and detect any whales that might have sneakily travelled underneath the ship to re-appear on the port side! However, this pair is more predictable in movement, and a powerful blow appears 600 m off the starboard side followed closely by the surfacing second animal. 

Having swum up to the ship, the whales now seem reluctant to travel underneath the vessel and towed seismic cables, and instead they turn to swim parallel alongside our trackline. The right-hand side of the whales is not visible, and we are unable to view the asymmetric white lower jaw diagnostic of fin whales. But the pale coloured chevron across the dorsal surface is readily apparent at this close range. The whales surface four times, before sounding with a steep roll of their tail stocks. Almost forty minutes after we first spotted them, the whales reappear around 1 km astern of us heading purposefully away".

June 23 2006: Chanonry Point, Moray Firth, North-east Scotland

Logbook 18:04 UTC 

"The bottlenose dolphins are up to their usual tricks at Chanonry Point . . . herding salmon in the tidal rip that races around the spit. And they seem more than aware of the 50 or so human observers that have gathered on the spit to watch them on the run-up to high tide. Their every leap from the waves is greeted with 'ooohs' and 'aaahs' from the appreciative crowd, in a chorus that reminds me of the response to fireworks going off on bonfire night! After a short, high-speed chase, one large dolphin turns with its captured fish and swims slowly along the surface with it in front of the human onlookers. It's almost as though, aware of the admiration, the dolphin is showing off its prize". 

Chanonry Point is probably the best place in the UK to watch dolphins, with one of the UK's two 'resident' bottlenose dolphin populations using the site year-round and frequently feeding within metres of the shore for prolonged periods.

June 2 2006: Research survey vessel, Aberdeen, North-east Scotland 

Logbook 12:53 UTC 

"We have been surveying the Aberdeenshire coast in idyllic conditions for three hours with only a brief sighting of a pair of harbour porpoises, when the sun glints strongly off a group of tall dorsal fins ahead of us. Changing course, we turn our vessel and head slowly in their direction. This group of bottlenose dolphins are moving steadily northwards off Cove (south of Aberdeen) and heading towards Aberdeen Harbour, one of their favoured feeding locations. The animals are very close to shore travelling only metres from the rocks with their sharp exhalations producing a light mist in the sunlight. 

Although there are several small calves present, the group seems very relaxed in our company. As we start taking photographs of their dorsal fins for individual identification, I notice something odd. Most of the young calves surface synchronously with associated adult animals, with a typical smooth rolling motion. However, one of the calves appears clumsy, pushing awkwardly through the water and leaving a wake of white water after each surfacing. Something also looks 'wrong' about the body shape of this calf, which appears strangely bulky. Although the loud blows around the boat tell me that the adult dolphins are very close and ideally placed for photo-ID work, I concentrate instead on trying to photograph the calf. Tracking it is difficult, since the water is murky and we can't see the animals when submerged. Moreover this calf is small (we estimate 1.2 m) and unpredictable in its surfacing behaviour. I manage to take several pictures, and then return to concentrate on photographing the adult animals.

It is not until we later download and analyse the images that we see exactly why 'our' calf looked so odd in the field. The animal has a large spherical lump on its right hand side behind the dorsal fin. The typical stream-lined dolphin body shape is markedly distorted, and it is no surprise that the calf was surfacing abnormally". 

Consultation with Bob Reid at the Scottish Agricultural College suggests that this calf probably has a congenital skeletal distortion.  The long-term outlook for this animal is not good, and we will hopefully be able to monitor its progress during future boat surveys along the Aberdeenshire coast.

18-29 April 2006:  Maldives, Indian Ocean

Cetacean images from a recent trip to the Maldives can be viewed HERE.  Spinner dolphins were the most frequently encountered species with a total of 24 sightings and at least 1,268 animals recorded during the 12 day trip. An account of some of the spinner dolphin encounters and observed behaviour is provided below:

"Glinting brightly in the sunlight, a procession of small dorsal fins breaks the surface beyond the turquoise outline of the reef. I glance at my watch, which reads 06:55 am - the dolphins are predictably on time. The night shift is over, and spinner dolphins are heading into the shelter of the coral atolls to spend the daylight hours. We are in the Maldives, an archipelago of atolls comprising over 1,000 coral islands situated southwest of India and Sri Lanka in the tropical Indian Ocean. These islands rest on top of an ancient volcanic mountain range, and the water depth drops steeply to over 3000 m within a few kilometres of the coast. Such habitats are highly favoured by spinner dolphins, which enter inshore waters to rest during the day, and move to adjacent deep waters to feed on a range of mesopelagic fish and squid species at night. The boat's engine throbs into life, and we move away from our overnight anchorage and over towards the dolphins. There are at least 100 animals present, although the school comprises a long line of smaller tight dolphin clusters that surface independently and are difficult to count accurately. The dolphins travel steadily through the narrow channel that marks the entrance between the turquoise coral reefs, and head towards the inner atoll. They are clearly winding down after the night's feeding offshore and seem lethargic, displaying only occasional aerial behaviour. The sharp 'puffs' of their exhalations sound all around the boat, as a small pod of dolphins momentarily approaches to swim at the bow. But they are not really interested in interaction. In fact, most of the dolphins simply detour sedately around our vessel and continue purposefully into the atoll. Our dawn-time encounter with the dolphins marks the beginning of their rest period, a prolonged siesta that will endure until mid afternoon when they begin to head out to sea again. Spinner dolphin encounters in the late afternoon have an entirely different ambience, being characterised by much higher energy levels. By late afternoon our vessel is heading back towards the atoll to anchor for the night, when amidst the whitecaps we spot the obvious splashes of many leaping dolphins. And they are unmistakably in a lively mood. We are fortunate to have met with another group of spinner dolphins, this time in the open ocean as they return to deep water for their night time banqueting. In sharp contrast to the sluggish nature of the school we encountered entering the atoll this morning, this group demonstrates the active 'other side' of spinners in a true Jekyll & Hyde style turnaround. Everywhere we look there are dolphins hanging above the horizon in mid-air leaps, producing huge splashes from their landings in the swell. The animals are performing their trademark 'spinning' leaps, emerging from the sea while rotating along their longitudinal axis several times before splashing back into the water. Individuals may fully rotate their bodies up to four times during a single leap, and frequently repeat these spinning leaps at a rate that leaves me feeling dizzy. It is an extraordinary feat of athleticism, and largely unique to this species. One animal emerges several metres above the ocean and spins particularly high and vigorously. As it crashes to the sea, I glimpse the blurred outline of a remora on its left flank.

The vivid whiteness of their undersides is shown clearly as one animal quickly turns upside down in an impressive display of synchronisation to mate with another while riding the bow-wave". 

The diurnal migration of the spinner dolphins between inshore and oceanic habitat is clearly important, since it occurs in many populations throughout the world. Spinner dolphins are very small (<2 m length and weighing less than most human adults) and are susceptible to predation from sharks and some larger cetaceans. Returning to the atolls during daylight hours allows them to rest in protection from open water predators. The dolphins then travel to deep water to feed at night, when efficiency of prey capture is maximised by the upward vertical migration of zooplankton, fish and squid. This nocturnal lifestyle is a neat solution to the challenges faced by small cetaceans in the three-dimensional oceanic environment.

March 29 2006:  Aberdeen, UK

Logbook 12:34 UTC

“I have recently relocated to Aberdeen, and there is one particular reason why . . . dolphins!  There are few other places in the UK where bottlenose dolphins can be seen so frequently and so readily from shore.  Aberdeen Harbour is a prime feeding area for this species, and the dolphins often spend many hours foraging between the breakwaters and sometimes even venturing far upriver to feed off the quays.  Despite the rather bracing, cold wind, the winter and spring months are particularly good times for seeing the dolphins, and it is possible to sit in a car at the mouth of the harbour to watch them in relative comfort.  Today I am observing around ten dolphins including two small calves and some exuberant juveniles.  Rather than feeding inside the harbour walls as usual, they are scattered widely on the seaward side of the south breakwater where their fish prey are clearly abundant today.  The dolphins spend most of their time quietly surfacing, and occasionally lifting their tails to embark on longer foraging dives.  I have watched their subdued surfacings for well over an hour, before any sign of increased activity becomes apparent.  The dolphins suddenly appear more coordinated in movement, with the scattered individuals heading towards one another in a synchronous move that suggests they are herding a school of fish.  With a burst of white water, several dolphins leap into the air and tumble over one another into the sea.  

The head and front half of a large animal rises from the water, and I can clearly see a large fish held between its jaws.  The feeding has commenced!  Donning my thermal jacket, I pick up my camera bag, head down to the breakwater and locate a suitable boulder to sit on.  I am just in time . . . the dolphins have clearly found a number of fish in the area and begin a burst of breath-taking aerial activity.  Repeatedly they surge from the water and plunge over one another, scattering spray in the sunshine.  It is almost impossible to keep up with them as they travel at great speed subsurface in fish chases, before leaping high into the air.  A group of four robust adults are particularly engrossed in a chase, and move closer and closer to shore in their frantic pursuit.  Herring gulls hover over them awaiting scraps of fish, and it is only by following the birds that I can tell where the dolphins will next emerge.  

One large animal performs a high leap, twisting in mid-air to drop back into the water on it's side.  The others porpoise rapidly above the water, and all four leap in synchrony from the water in a sequence most people would only expect in dolphinariums!  I wonder whether they are all chasing a single large and particularly tasty-looking fish or whether they are herding an entire school of prey below the water, but it is not possible to tell.  Suddenly the action ceases, and the dolphins tumble over each other one final time as their prey is obviously caught.  Slowly, they turn from shore and head sedately out into deeper water to start herding again”.

March 26 2006: Forvie Sands, Aberdeenshire, North-east Scotland 

"It is always a mixture of sadness and interest to see a dead whale washed up on a beach. The vast bulk of a 10 metre male sperm whale looks particularly out of place lying lifeless on the golden sand. Although it is regrettable that this ill-fated whale has ended up ashore, I am fascinated at the opportunity for a close-up view of its broad tail flukes, tiny flippers, blow-hole and huge head. Part of the whale's lower jaw has already been removed by researchers from Aberdeen University and taken away for analysis. But most of the narrow jaw remains, complete with rows of large conical teeth on either side. It is impossible not to consider the life and travels of this huge animal, and ponder how it ended up here in the North Sea, many miles from its usual deep water habitat". 

During February and March 2006, at least five male sperm whales stranded along the North Sea coasts of England and Scotland including Humberside, Lincolnshire, Norfolk and Aberdeenshire. Mature male sperm whales reach lengths of around 18 m, and at reported lengths of 9-10 m these stranded animals were all sub-adults. Immature male sperm whales often occur together in assemblages known as 'bachelor groups', and it has been suggested that one such group strayed into the North Sea from their usual deep-water habitat. However, with one animal stranding alive and others already in a state of decomposition it is not known for certain whether the strandings were related, or what may have caused them to erroneously enter the North Sea.

January 26 2006:  Angola, West Africa, Seismic survey vessel

Logbook 07:34 UTC

“It has been a long five weeks at sea, and on this particular survey Angola has produced little cetacean activity of note.  In fact we have logged only 22 sightings in the entire period, and many of those have remained unidentified due to their distance from the ship and the brevity of the encounters.  Nevertheless it only takes one special sighting to make for a wonderful trip, and instead of heading down for coffee break I decide to go back out on deck for a quick look over the sea surface.  The sea looks grey and choppy as before, and I scan around the vessel without much hope.  However with some shock I notice a tall black triangle disappearing below the water, only a few hundred metres off our port bow.  My first thought is that this must be some piece of seismic gear or other survey-related equipment in the water, but the triangle was creating a pressure wave that indicated it was moving purposefully by itself!  The butterflies in my stomach inform me more reliably that this can only be a long awaited sighting of one of the most charismatic cetacean species in the ocean . . . killer whales!  This sighting has been 'long awaited' because it was back in January 2005 that we encountered several groups of killer whales in deep water off northern Angola, and I had been hoping for another sighting at the same time this year to add weight to the theory of seasonal occurrence of this species off Angola!  I can hardly believe that after five weeks of so little action, we now have killer whales off the bow!  I hesitate to run for my camera, since I would really like to see the animals properly before I alert the bridge.  As if on cue, three female/immature killer whales surface off the bow and this time even closer, their white eye patches conclusive proof of identification.  I make a hasty journey to the bridge, and can't resist shouting 'killers!' to the bemused officers keeping watch.  They look up in time to see the animals dive off the bow, and I can tell from the curve of the animals' tail stocks that they will not surface again for a few minutes.  I locate my camera and return to the bridge roof, expecting the animals to reappear off the starboard side.  It is a few minutes before they surface, their powerful exhalations producing a tall visible blow.  And this time I see the owner of the tall, black fin that undoubtedly caught my eye at the beginning of the encounter - a huge bull male with a massive triangular dorsal fin that must reach almost two metres in height.  

The killers travel steadily away from the ship in a southerly direction and I try to take photographs of their eye patches and pigmentation that might be useful in determining the ecotype of these animals.  Killer whales worldwide occur in various 'forms', that inhabit different habitat types, show variation in group size and specialise on different prey.  Our knowledge of killers off West Africa is in its infancy and photographs are very important in comparing the sightings.  As I hold down the shutter to capture the entire group surfacing, a tiny calf appears briefly between the bull and the female/immature animals.  This is the first killer whale calf that I have observed in Angolan waters, and it is great to see the youngster swimming side by side with the enormous male!  The bull's dorsal fin is visible well into the distance as the family continue on their travels, leaving me very happy with both a fantastic memory and some important data”.