Studying Basking Sharks in Scotland: Research Diary

At the same time, Song of the Whale was also on the look-out for minke whales (Balaenoptera acutorostrata).

Scientists have developed a method of finding out what whales have eaten by conducting sophisticated DNA analysis of their feces. No one has ever before collected minke whale feces, so the Song of the Whale team looked into ways of collecting samples. Any samples would have then been analyzed to learn more about the diet of the minke whales that frequent the waters of the Inner Hebrides Islands -- and to counter claims that whales must be killed to find out what they eat.

You can follow the progress of the Song of the Whale team's Inner Hebrides research journey through their field diary entries, below.

Monday, 9 September 2002
Song of the Whale sets sail at 08:30 from the Isle of Muck, one of The Small Isles off the west coast of Scotland. It’s a clear day with light winds, so we head northwest for Hyskier and Canna in search of basking sharks.

At 09.40, just off the islands, Richard spots our first two sharks for the day.

Numbers of sharks increase throughout the day, until we have 16 sharks within sight of the boat. Many of these huge fish come close, and we can see them filter-feeding around us.

We take plankton samples in order to confirm the type of zooplankton (minute marine animals) on which they are feeding, which we suspect might be Calanus finmarchicus, a species of copepod (tiny crustaceans).

Some animals are seen swimming nose to tail, a previously reported behaviour of basking sharks at the surface, which might be indicative of social activity. We selectively track five individual animals using the video range-tracking technique developed by the team onboard.

We manage to track one individual with a distinctive notch on his dorsal fin for some time. We also spot what is probably a juvenile shark swimming around the vessel.

We take Conductivity, Temperature and Depth (CTD) readings with the CTD probe, as well as plankton samples, both with the sharks and three miles away from them, in order to compare the water properties and plankton samples.

In the late afternoon, the weather closes in and we are forced to anchor off Eigg, four miserable hours sail away through driving wind and rain.

Tuesday, 10 September 2002
We leave Eigg in glassy conditions and head towards Arisaig on the mainland to pick up Russell and Kara, who have arrived on the train from Fort William.

On the way we sight several minke whales. Data, including their distance from the boat, direction of travel, time of sighting and distinctive markings are fed into Logger. This software, developed by Song of the Whale researchers, enables us to record small-scale movements and behaviours of our subjects.

Photographs were taken of the animals in an attempt to identify them (whales can be identified through individual distinctive markings on their dorsal fins or elsewhere).

As soon as we pick up the extra team members from the mainland, we head back to the coordinates of the earlier sightings. We sail toward "hurries" of sea birds – dense flocks of feeding sea birds on or above the water -- which indicate fish activity near the surface. They can be a clue to the presence of filter-feeding minke whales.

Sure enough, we are soon surrounded by minke whales, and also take record of harbour porpoises busily feeding in the area.

The relatively calm seas mean we get good views of the minke whales as they swim under the boat, at times rolling over to show their pale underbellies or the white "armbands" on their flippers. We take video and photographic recordings of the whales as they lunge at schools of small fish and invertebrates, the pink of their extended throat pleats showing as they feed.

Russell takes samples of fish scales left floating on the water; these will be analysed to help identify the prey species of these whales.

The main aim of the minke whale project is to collect faecal samples for DNA analysis to counter claims that whales must be killed simply to find out what they eat.

Despite carefully investigating the slicks or "footprints" left by the whales as they dive, with plankton nets at the ready, today we fail to find a sample. The wind picks up, making observation difficult, and we anchor back in Arisaig as the sun sets.

Wednesday, 11 September 2002
Strong winds and heavy rain keeps us anchored in Arisaig. The interns head off to the bright lights of Fort William while the rest of the team collects and responds to urgent emails and calls, and catches up on paper work.

Thursday, 12 September 2002
After last night’s stunning display of the Aurora Borealis, or Northern Lights, we slip our Arisaig mooring at 0700 – the earliest the tide will allow.

It’s a calm, clear morning and we pass seals, shags (cormorants), and porpoises as we head out of Loch Nan Ceall in search of basking sharks. We spot a minke whale even before we reach open water, but steam ahead for the little isle of Hyskeir where we recorded numerous basking sharks feeding on Monday.

But when we reach the eastern edge of the island, where only 48 hours ago we spotted 16 baskers – or "muldoans" as they're known locally -- we make no sightings. We try our luck around on the west side of the island, and soon spot our first shark. We don’t know why the sharks have switched feeding grounds; just another mystery that we hope our surveys can help solve.

Again we see small fish jumping close to the sharks, and gannets making spectacular dives. Gannets catch small fish underwater by folding back their wings in flight and plunging through the surface. Russell takes video footage of diving gannets and, by using the video tracking software, hopes to calculate how fast the birds are traveling when they hit the water.

When we find the sharks, we drop a buoy with a drogue (sea anchor) attached so it moves with the tidal current. We also attach a Global Positioning System (GPS) to record the speed and direction of the buoy with the current, which may carry plankton.

One thing we are interested in is how much water the sharks filter through their giant gill rakers. To measure this we need to know the sharks’ movements relative to the water as well as relative to the land.

We are fortunate to spot and record ten sharks throughout this afternoon. But this is nothing compared to the encounters by basking shark fishermen in Scotland in the late1940s, when large numbers of basking shark were evident.

Writer Gavin Maxwell, who fished for basking sharks near Hyskeir in 1947, recorded one mass sighting in his book, "Harpoon at a Venture" (1952):
“It was a gigantic shoal ... at one moment we counted 54 dorsal fins in sight at the same time.” Fifty years on, it takes us perseverance and a full lookout team to find our sharks. As the sun drops, we head in a northeasterly direction, towards Canna, where we anchor for the night.

Friday, 13 September 2002
Are we really in northwest Scotland?

For an area synonymous with wet summers and wild seas, the Hebrides are blessing our project with fine weather. We return to the east of Hyskeir – where we had no luck yesterday – and, interestingly, the sharks have returned to that side of the island.

Throughout the day we find ourselves in the middle of small groups of three or four sharks, including one large animal with very distinctive white markings on its back, which seems to take an interest in the dinghy towed behind our boat. Looking through the clear water at the massive speckled body and luminous, white, gaping mouth which dwarf the dinghy, puts the size of these fish in startling perspective.

As our protocol determines, we video range track and photograph individual animals for identification purposes and take plankton samples and CTD measurements.

Our research is suddenly interrupted by a massive splash; one of the sharks has breached, thrusting its five tonne body in the air and belly-flopping back into the water. Marine scientists don’t know for certain why sharks exhibit such startling behaviour. Possibilities include getting rid of parasites or communicating with other basking sharks. Whatever the reason, breaching sharks have been known to destroy small ships.

In his book, "The Basking Shark in Scotland", Denis Fairfax reports that on 1 September 1937, a Scottish boat called “The Eagle” was fishing in waters where “...sharks were leaping out of the water non-stop,” when there was “a big splash and then the boat was on its side with the mast at an acute angle.” Two fishermen perished before the “bruised and cracked” hull was recovered.

For us, the surprises don’t stop here. As we sail east toward the Isle of Muck, Anna spots a large male killer whale (Orcinus orca).

Its distinctive dorsal fin breaks the surface of the water just off the boat, and we rush to grab cameras to photograph its unique grey saddle patch (behind the dorsal). This is the part of the body on a killer whale which is distinct and is used to identify individuals.

After two surfacings, the whale disappears for several minutes and we all scan the sea surface anxiously for a sign that it has resurfaced: a splash, a blow or another glimpse of its massive fin.

As we scour the waves, someone notices a dead bird drifting behind the boat. Upon investigation, we find the freshly stripped skeleton of a shearwater. Had it, we wondered, provided the killer whale with a snack?

A cry of “blow” alerts us to the fact that the killer whale is visible again.

This time, he speeds directly towards the boat, submerging alongside us, and turning underwater to reveal the clear white patches on black which are the distinctive livery of killer whales. "He’s checking us out!" shouts Steve, from his vantage point on the A-frame. The whale turns underwater, descends into the murky deeper waters and dives under the boat, resurfacing on the other side.

After a couple more distant surfacings, we see no further sign of the whale and so reluctantly decide to continue our passage towards Muck. Local whale-watching vessels have only two or three sightings a year of these exciting toothed whales, so we feel most privileged to have had this close encounter today.

As we steam towards Muck with the glow of the setting sun behind us, we are met by a school of white beaked dolphins (Lagenorhynchus albirostris). These beautiful white, grey and black dolphins can be found throughout Scottish waters. We enjoy watching their leaping and bow-riding on the pressure wave in front of the moving boat.

After a short while, the dolphins head off towards the open sea. We continue motoring and reach Muck in darkness to anchor in a sheltered bay for the night. We begin anchor watch to ensure that we don’t drag anchor and end up in danger. Some people head off to bed immediately to catch some sleep, mindful of the fact that they will be awake for an hour or two in the middle of the night or early hours.

Saturday, 14 September 2002
The morning dawns clear and calm and we set off to look for whales in known, favoured grounds between Eigg and Arisaig. Unfortunately, before too long, a dense fog rolls in from the west causing us to retreat back towards Muck and the mainland.

As the foghorn sounds its warning from Ardnamurchan lighthouse, we sight three minke whales.

We successfully track one animal as it comes to the surface to breathe. As we’ve noted before, the whale surfaces for three or four blows before diving deeply, leaving us scanning the horizon for its next appearance. This can be a lengthy wait, as minke whales can stay under water for up to 20 minutes.

There is a chance of faecal matter remaining in the whale’s slick, so we manoeuver the boat to the oily patch of water left as the five to ten tonne animal takes a long dive.

We repeat this cat-and-mouse game with the whale’s "footprint many times this afternoon, but again and again we fail to find a sample and our net remains empty.

It is pertinent – and galling – to remember that any of these animals we are studying at close range may be hunted if they migrate to Norwegian waters. They may end up on dinner plates in Norwegian homes and restaurants.

Norway kills more than 600 minke whales every year, despite the International Whaling Commission's ban on commercial whaling. Even if this whaling moratorium were lifted, Norway would still be taking more than the procedure agreed by the IWC scientists would allow.

If we are successful in collecting minke faeces for DNA analysis of their diet, the research may help to demonstrate that much of what the whales eat includes invertebrates and fish species that are not of great commercial interest to humans. This may help counter claims that whales are eating all "our" fish, thus justifying their inhumane and unnecessary killing.

Tonight it’s not the setting sun that makes us hurry for a safe mooring, but the banks of fog that have hampered our tracks all day.

It’s early when Steve, standing in for Richard as skipper, navigates us to the shores of Eigg.

This means there’s time for a moonlit visit to the island – but the tradeoff is that we’re lifting anchor as soon as the sun rises tomorrow morning. After three days on the boat, our impromptu walk on land sends everyone early to bed, at least until their rude awakening for anchor watch!

Sunday, 15 September 2002
An unpromising start to the morning. Fog shrouds Eigg.

Up early, expecting to leave at day break, the team are left with little to do but eat toast and wait for the world to come into vision. Today we must sail to the mainland to drop off Helen, pick up fuel and relish in a (much-needed) shower at Arisaig Hotel. We resign ourselves to a day of necessary drudgery and housekeeping. When the fog begins to clear around 10am, we head off.

The sea has many ways of throwing us surprises, and none better than an inquisitive young minke whale.

The "small" (around five metres or 16.4 feet) juvenile seems extremely curious. It sticks its whole head vertically up above the water's surface (a behaviour known as spyhopping) allowing us to take detailed footage of its double blowholes and long pointed rostrum.

The calf has a distinctive notch on its dorsal, which could give us a clue to its movements in the future. It decides to spend nearly an hour with us, swimming away then speeding back towards the boat to "investigate" the zodiac, which gives us plenty of opportunity to film its movements and appearance at close quarters.

After feeding eight hungry people 'round the clock, the ship's stores are running low. Anna and Kara drive to Mallaig, a fishing town on what's labeled the "Road to the Isles", to empty the local shops of pasta, bread and oranges.

We meet the rest of the team, who have sailed around the coast from Arisaig, in Mallaig harbour, where we tie up, dwarfed by fishing vessels, Caledonian MacBrayne ferries and the RNLI lifeboat.

Stacking away 17 bags of groceries in a 46-foot boat is a science in itself -- toilet rolls stashed above bunks, long-life milk stowed in the bilges, and catering-size tins of soup stacked beside Polish breakfast cereal and German biscuits, remnants of Song of the Whale's previous survey work for harbour porpoises in the Baltic Sea.

Despite the gloomy start, it was not a bad day after all.

Monday & Tuesday, 16 - 17 September 2002
Monday marks the start of three days of visits from TV crews interested in filming Song of the Whale in her element.

Song of the Whale has starred in numerous TV broadcasts throughout Europe, Canada, the USA, and in the Caribbean. The scientific research carried out onboard is one of IFAW's most powerful tools to advocate for greater protection and understanding of marine animals and their habitats.

First in line is a Scottish television crew, keen to film our work with Scotland's largest and most charismatic coastal visitors.

It's always good to know that news teams are interested in our research, even if it means a 6:00 am start and a long, cold day at sea. Their patience is rewarded as we are able to observe a number of whales throughout the day (some of which are lunge feeding), and are also able to film the porpoises and grey seals which
have been an added bonus to each day we've been in the Hebrides.

Our recurring disappointment is that -- despite more than 50 sightings of minkes -- we are no nearer our goal of collecting a faeces sample. Even the presence of national media fails to cajole our whales into delivering what we desperately seek!

One restraint with media visits is that even the keenest crew can only spend a limited time with us, and so we are unable to make the 10 hour round-trip to where we last spotted the basking sharks.

Instead, we provide our own digital video footage from the hours of range tracking we have successfully filmed in the past week. That way, the story of Scotland's sharks and the measures needed to protect them can still go out.

The state-of-the-art technology onboard Song of the Whale allows us to communicate our first-hand experience of studying whales and basking sharks in their natural habitats around the world.

Wednesday, 18 September 2002
This morning, the film crew of the BBC’s "Country File" join us for the day. Their film is focused on basking sharks, and we take them to the tiny island of Soay, which is very close to the Isle of Skye.

This island was bought by Gavin Maxwell in the 1940s, where he founded the "Island of Soay Shark Fisheries Ltd," a factory for the processing of shark liver oil (and other shark products). The factory was only active for three years, before financial pressures, declining shark numbers, and logistical problems forced it to close.

We scramble ashore up the old, now seaweed-strewn slipway, where the sharks would have been hauled ashore and butchered. Wandering around the derelict buildings and broken, rusty machinery, it is hard to imagine the place in the days of the shark factory, then noisy, smelly and gory.

It is now a beautiful, tranquil spot. Only the rusting "mincers," old steam boiler and foundations of the factory buildings give a hint of the past activities there.

As we return to Mallaig, we spot some minkes feeding near a hurry of birds. The film crew is delighted (this being the first encounter with a whale for some of them) and go on to get some good footage.

As we continue towards the harbour, Russell spots some Risso’s dolphins (Grampus grisus) on the horizon. It is unusual to see this species so close to shore here; they usually prefer the deeper waters of the continental shelf.

It was the first time some of the Song of the Whale team had seen these dolphins, which are easily recognizable by their scar-covered skin and blunt forehead. The scarring, which increases with age, occurs all over their bodies, caused by the teeth of other Risso’s dolphins, and sometimes the squid upon which they feed.

Thursday, 19 September 2002
Song of the Whale slips the mooring in Arisaig at dawn to make way out of the narrow channel while the tide is high. Kara, Russell and Anna have returned to their offices to catch up with other important business and Dr. Nick Tregenza has joined the boat to assist with field work.

The skipper sets a course toward Soay to more thoroughly investigate the area where the team encountered minke whales and Risso’s dolphins yesterday.

A couple of miles off Soay, Nick spots a minke whale to the north of us. We stop and wait for another surfacing near a hurry of birds and spot a second, much smaller minke whale, lunging through the water close to the hurry. We wonder if this is a mother with a calf who has started to feed on fish.

The whales don’t stay long, and we have to make the tide in order to get back into the harbour, so we head back towards Arisaig, encountering harbour porpoises on the way.

Saturday, 21 September 2002
This morning we have two members of the GBR Women’s Olympic Curling Team coming aboard to help us raise awareness of our campaign.

It is hard to tell who is more excited; us, to see the gold medals, or Debbie and Janice to see minke whales and porpoises. We are rewarded by being allowed to take our pictures with the gold medals. The Olympians are rewarded with a breaching minke whale.

The minke was seen on the horizon just by the entrance to Arisaig harbour. It breached several times in succession.

Breaching is a behaviour common in several species of cetacean, such as the humpback whale (as well as the basking shark). Breaching may have several possible functions including parasite removal, communication, and fun.

Sunday, 22 September 2002
Nick Tregenza has built an underwater viewer from scrap building materials at Russell’s recently renovated house.

Once we find some minke whales, Nick and Russell quickly disembark Song of the Whale to the zodiac, where faecal collection gear is at the ready.

The people onboard Song of the Whale radio the zodiac to direct them to the whales. With the underwater viewer, they get lots of close looks at "fluke prints," the slick created by the upward stroke of the whale's tail as it dives. Other large whales, such as sperm whales, defecate during their terminal sounding. We are hoping that minke whales do the same. The terminal sounding is the last breath whales take before diving for prolonged periods.

Unfortunately, we don’t find any minke faeces today, even with the help of the viewer.

Monday, 23 September 2002
We are down to five people today as Russell has gone home again to catch up on office work.

The sea is like a mill pond, and in no time at all we are spotting minke whales feeding and traveling.

We are too few people to use the zodiac "rapid response unit" today, but Alison Gill (a visiting scientist and minke whale enthusiast) takes lots of samples of the fish scales, which can be seen floating in the water once the "hurry" has finished. She hopes to be able to use these to establish the prey species of the birds and whales seen feeding in the hurries.

As the weather is so good, we follow up a report that basking sharks have been sighted off the south coast of the Isle of Muck. Sure enough, we soon find three sharks, one of which has a very distinctive nick in the front edge of its caudal (tail) fin.

In addition to video range-tracking, we also make sure we have good photo ID pictures of these three sharks in order to find out whether we have seen the same individuals before off Canna, where we were working previously.

Tuesday, 24 September 2002
A cool, crisp and windless autumn morning dawns and Song of the Whale takes advantage of it by setting course for the small outlying island of Hyskeir to investigate the presence of sharks in the area we had found them the week before last.

It is generally thought that the basking sharks leave the coastal waters around Britain by late September, so we are interested to see if there are still sharks in the area. Where they spend the winter is still unknown.

Soon after we begin our search of the bank south of Hyskeir, we find three sharks. Like yesterday, photo ID is a priority. As well as identification, we also aim to get accurate length estimates for the sharks. This can be done from the photographs, which need to contain three useful pieces of information: the horizon, the nose or tail, and the dorsal fin of the shark.

Current size estimates for basking sharks range up to 8.8 metres (28.9 feet), although Gavin Maxwell hunted specimens that reportedly reached a length of more than 12 metres (39 feet).

We also follow one basking shark for an hour and a half with the video range-track apparatus so that we can study its small-scale movements. We sight several more sharks on the way to Canna; we see ten altogether by the end of the day.

Wednesday, 25 September 2002
This morning dawned to a blustery day so we set sail for Tobermory on the island of Mull to pick up a minke whale faecal sample from the skipper of the Sea Life Surveys vessel, "Alpha Beta."

Sea Life Surveys takes people out to see minke whales and basking sharks around the Isle of Mull.

The Alpha Beta crew had been fortunate enough to be watching a minke whale when it defecated. And knowing that we were interested in obtaining a sample, they excitedly scrambled to retrieve some before it dispersed.

We are sailing along nicely on a broad reach in rough seas and discussing whether or not minke whales breach more when it is rough weather when, suddenly, a minke whale breaches completely out of the water while spinning around longitudinally 360 degrees, just 100 metres from the boat. (Like basking sharks, whales sometimes leap clear of the water, perhaps to remove parasites, as a form of communication, or just for fun.)

The whale then surfs toward us and dives under the boat before heading off toward Ardnamurchen Point. Soon after, a small basking shark passes very close to the boat. When the conditions are rough it is much more difficult to spot animals at sea.

Thursday, 26 September 2002
We are up before dawn and heading offshore as it starts to lighten.

We sail north past Bloody Bay on Mull when we spot a curious minke whale that spends some time with us. It has a distinctive nick in the dorsal fin; Alison recognizes it as an individual minke whale that has been photographed previously and so is in the photo-identification catalogue. It is minke whale Number Two.

The whale spends a lot of time close to the boat. That, and the appropriateness of its catalogue number, make us hopeful that this will be the whale we retrieve a faecal sample from.

Alas, it is not to be.

Number Two moves off. It has started to rain. We decide that it is best to head back to Tobermory and get some essential maintenance done.

Friday, 27 September 2002
The weather is beautiful again so we seize the chance and strike out early to head for waters that seem popular with the minke whales east of Eigg.

We find a few whales, two of which are very small, obviously juvenile, minke whales. There are some hurries of birds in the area, but things seem less lively then they did at the beginning of the month.

At the end of the day, we head for an anchorage on the mountainous Isle of Rhum.

As we pass the northern end of Eigg we are treated to a visit from a group of harbour porpoises. The conditions are just right and enable us to hear and see their blows, something normally invisible.

After the months of searching for porpoises in the Baltic earlier in the summer, this is a wonderful spectacle at the end of a long day.

Saturday, 28 September 2002
We wake up at 0700 and take some time to go a shore. Rhum, now owned by Scottish Natural Heritage, is home to a lot of wildlife as well as a grand old mansion that is now a hotel.

Nick is keen to see some deer and sits on a remote hillside to look out for some. He sees none, but from their vantage point below, the rest of the team can see deer further up the hill watching Nick from a distance!

After a quick tour of Rhum we leave and head for one last survey of the waters around Canna and south toward the Island of Coll.

Once we pass from behind the north side of Canna we lose our protection from the moderate seas and decide that the last day of surveying we had hoped for is deteriorating.

When whitecaps become persistent, searching for whales and sharks becomes difficult. Taking good pictures and video gets hard, too. So we set course for Tobermory one last time.

We sail in, passing Ardnamurchan Point and its distinctive lighthouse, the most westerly point of mainland Britain. We pick up a mooring in Tobermory Harbour.

Tomorrow we will haul our dinghy up onto the fore deck in preparation for the return trip through the Caledonian Canal. Once through the canal we will head south to Ipswich, England, and Fox’s Marina where "Song of the Whale" was first launched twenty-two years ago. Here she will be readied for her next voyage into the field.

Our hope is that the data we have collected during the month in Scotland, on the small-scale movements and distributions of individual basking sharks, will contribute valuable new details to the small, but growing pool of information on basking shark biology and natural history.

Basking sharks, although now protected in British waters, still suffer from widespread, cruel hunting practices and uncontrolled trade in their parts in other areas.

We urge countries to help conserve basking sharks at the forthcoming CITES meeting in November 2002 by listing the basking shark on Appendix II, which will impose some controls on fishing and the trade in shark parts.

We want to ensure that the depleted populations of these magnificent, little known, and elusive creatures around the world are allowed the chance to recover.