They’re among the most intelligent creatures ever to have lived on Earth So why ARE so many whales and dolphins dying on our beaches?
As strandings soar, scientists face a race against time to pinpoint a cause ...and help save these giants of the sea
IT is a harrowing sight even for battle-hardened veterans of mass strandings – pristine white sands strewn with the helpless bodies of the dead and dying.
Stretched out along the arcing spit of Tresness Beach in Orkney, the line marking the biggest mass stranding of whales in Britain for nearly a century appears to run on forever. In this place of natural beauty, a tragedy of unthinkable proportions has played out.
Alerted to the discovery, volunteers raced to the scene to attempt to refloat the survivors. When the pod was first found by a walker, only 12 of the family group of 77 were still alive, thrashing their tails in distress and gasping for breath.
By the time reinforcements arrived, it was clear that even these survivors were beyond help. With the tide out of reach, hopes of returning them to the sea evaporated and even keeping them comfortable, let alone alive, was proving impossible.
Slumped on their sides, these magnificent creatures were slowly suffocating as the rescuers tried in vain to right them. In the end, there was no alternative but to put them out of their suffering.
Among the group trapped on the soft sands of Sanday island were year-old calves, adult females and a fully grown male 23ft long. Seasoned conservationists have described the scene as ‘heartbreaking’.
One of the hardest things to cope with is the noise these suffering animals make. ‘I know exactly what the folk on the ground would have been feeling like,’ said Colin McFadyen, Scottish co-ordinator for British Divers Marine Life Rescue, whose volunteers helped the rescue effort.
‘Most people tend to think of whales as being relatively quiet, but when you are walking among them and you can hear them squealing and clicking to each other, when you can hear them getting frantic, it does hit you emotionally.’
OFTEN the marksmen called in to euthanise stranded whales can find themselves overcome by unexpectedly strong feelings: ‘I’ve seen ghillies, who have absolutely no problem with putting deer and other animals out of their misery, become quite shaken up having to shoot whales,’ added Mr McFadyen.
‘They have got quite tearful and emotional. For some reason, you engage with whales a lot more than you do with other animals, regardless of how much empathy or experience you have with other species.’
As with any natural disaster, the fight to save lives is only the first part of the mission. The second, equally vital task, is finding an answer to the key question – why did the whales become stranded?
The answer to that may lie in the expertise of the biologists, pathologists and vets who also raced to this remote island archipelago to inspect the carcasses of the doomed pod. Around 30 people worked against the clock – and the natural process of decomposition – to collect and preserve around 2,000 samples of brain tissue, blood, skin and blubber.
At the micro level, the hope is that signs of ill health may be detected that could hint at a cause. Were they, for example, suffering from illness or following a sick leader who was too unwell to make sound decisions?
Or was this a man-made disaster? Were the whales – who rely on sonar and their sensitive hearing for communicating, navigating, hunting and feeding – disorientated by noise disruption in our increasingly raucous oceans?
And while divining the truth of the stranding at Sanday may prove a tall order, the results of clinically testing these sentinels of the deep may at least reveal critical data about the wider health of our oceans. For the Scots scientists at the forefront of this research, that could prove a hugely valuable exercise as they prepare to publish research which suggests mass strandings are not only becoming more common, but are happening on an ever larger scale.
The Sanday stranding is certainly not unique. It is only a year since an entire pod of 55 pilot whales beached on the Isle of Lewis. All but one died.
There was a mass stranding of 74 animals in 2011 in the Kyle of Durness, Sutherland, a group of more than 40 stranded on the Fife coast in 2012, and a pod of at least 21 on the island of Staffin in Skye in 2015, although most were refloated.
‘With pilot whales, there have been roughly 13 significant mass stranding events in the 32 years that we’ve been monitoring this and of those 13 cases, ten have been since 2010,’ said Dr Andrew Brownlow, director of Glasgow University’s Scottish Marine Animal Stranding Scheme (SMASS).
‘So we’re seeing an increase in the frequency of these mass stranding events – they’re happening more often – and we’re also seeing an increase in the magnitude of them, as in when they do happen, they tend to involve more animals and therefore they’re more significant.’
A GLANCE at the SMASS database map also shows a bewildering number of strandings involving other species, from sperm and minke whales to bottlenose dolphins, as well as numerous other species washing up dead on our shores, from harbour seals and grey seals to porpoises and marine turtles. Mass strandings involve three or more animals at a time.
Yet to be added is another rescue on Orkney last week – this time successful – involving the refloating of three Risso’s dolphins, where members of the public administered first aid until medics arrived.
Dr Brownlow said the Sanday event was particularly perplexing as initial inspections suggested the animals were well-fed and in good physical shape. They were stranded close together, however, which may point to a behavioural stress response, meaning something could have frightened them – like a sound or a predator – and made them cluster.
The investigators have taken ear samples from six key whales to look for acoustic trauma. ‘There were so many of them that we think that there had to be something that caused them to do what pilot whales do when they get disturbed by whatever source. It can be killer whales, it can be earthquakes or it can be human noise,’ Dr Brownlow said.
‘They tend to have a behavioural response, which is where they form these big ball groups that
kind of spin around each other so they can communicate with each other and they’re kind of safe.
‘You see it with a lot of bison or wildebeest. The concern is what might have instigated that because that’s probably why you ended up with 77 animals stretched on half a kilometre of beach.’
The whales’ hearing may be key to understanding what went wrong. In the past, some pods are thought to have been caught out by following prey onto sandy beaches where their sonar often fires back at oblique angles, fooling them into thinking the water is deeper than it is.
‘This is a species that uses sound to communicate, to find food, to navigate, for all of the basic life processes,’ explained Dr Brownlow, ‘so if there’s something up with the hearing or their ability to echo-locate, then that could be majorly important.
‘If there’s been an excessive noise or protracted amounts of noise, then cells in the auditory apparatus can become damaged: they don’t repair.
‘But the problem is, there are a huge range of behavioural responses to noise or disturbance, both human and natural – be it earthquakes or killer whales or the usual suspects like sonar, military activity, pile-driving or detonation of explosives – and not all the ways a socially complex animal responds to those can be detected at post-mortem. You can’t detect if it’s scared, if it’s lost, if it’s made a bad decision.’
SMASS, which is based just west of Inverness, will sift through all available information, from postmortem examinations, lab tests and even records of underwater activity. It has asked the Ministry of Defence and civilian noise producers if they were doing anything unusual in the water beforehand and will look for natural causes as well, such as unusual weather or geomagnetic activity.
Civilian noise pollution could come from surveying for marine renewables or underwater cables or commercial shipping passing by with an engine emitting a particular frequency of noise.
‘I’m not saying it is any of those things,’ said Dr Brownlow. ‘And checking is time-consuming and complex because the ocean is not a quiet place any more, certainly not around Scotland.’
HE added: ‘Understanding the marine environment is difficult but we can ask the obvious questions, you know, did anyone blow up any underwater explosives during that period like they did with the strandings at Durness in 2011 (Four bombs exploded underwater by the Navy were blamed for that mass stranding which killed 19 pilot whales).
‘Were there some significant geophysical surveys going on in the vicinity of Sanday or was the military playing war games. Those are the questions we can ask and, in some cases, might even get answers to.’
Pilot whales are social animals that can live in small groups, but also in giant pods of more than 1,000. They have a prominent curved dorsal fin. They can be found across the north Atlantic, the North Sea and the western Mediterranean and they hunt squid, mackerel and cod.
Throughout history whales have died in mass strandings – with the largest recorded in the UK in 1927 when 126 whales died in the Dornoch Firth. Traditionally, the north and west coast of Scotland and Cornwall witness the lion’s share, due to their proximity to the deep waters of the Atlantic.
That wider marine environment is part of Dr Brownlow’s focus as the creatures that inhabit it are normally difficult and expensive to get access to. A tragedy like Sanday at least offers the chance to unpick some of those mysteries. ‘Trying to understand the health of the marine environment is hard,’ he said. ‘It is in every sense fluid. You know, things move in three dimensions and drift.’
One way to achieve it is by examining the health of pilot whales and other creatures that feed close to the surface because they consume animals such as fish and squid that dwell lower down.
‘[Whales] integrate all of the threats and pressures that are happening lower down and code that into the tissues in their body. So by looking at those tissues, we can gain, potentially, insights not just into these 77 individual animals or this species of pilot whales, but actually into kind of wider issues of ocean health.
‘It is a curious job to go and drag a dead animal off the beach and find out what’s happened to it, but it allows you a window into a process that is otherwise very difficult to get insights into.’
THAT glimpse into the deep tells a worrying tale. ‘The ocean environment seems to be changing,’ he said. ‘We’re seeing a change in the distribution of species, an increase in the number of warm water species that are coming into our waters, we’re seeing an increase in the number of large whales, which are sadly actually becoming entangled [in fishing gear], but that might actually be because these populations are recovering.’
A moratorium on industrial whaling since the mid-1980s has helped species recover and return, but Dr Brownlow pointed out: ‘While they have been gone from our waters, we have done a very good job of industrialising further the waters around Scotland.’
The biggest single threat to cetaceans globally is from fishing – anything from entanglement in fishing nets to problems with ‘ghost gear or marine debris’, such as kilometre-long stretches of rope that are abandoned in the deep ocean to plastics and microplastics which cause problems when ingested. There is also the risk from chemical pollutants.
‘The good news is populations might be increasing,’ said Dr Brownlow. ‘The bad news is that they’re coming back into slightly more hazardous waters.’
Meanwhile, all but one of the doomed pod have now been buried on Sanday, while one of the whales has been left behind so it can decompose and its bones can go on permanent display at the Sanday heritage Centre. Teeth and bone samples from all 77 whales were collected by National Museums Scotland for its extensive natural sciences research collections, used by researchers from around the world.
Dr Brownlow and his team hope to create another, more practical, legacy: ‘There were 30-odd people who dropped everything and went to Sanday to try to work out what was going on because they wanted to do right by these animals. Because they are very traumatic and emotional events that affect you quite profoundly.
‘We have a duty to ask if this is something we have caused and try to make sure it does not happen again.’