Fin whale from above, showing asymmetrical blaze and chevron markings on the right side, used to identify individual whales. Danny Kessler
Giants of the Undead Med
IN MARCH 2015, the epicentre of the world refugee crisis was a tiny Italian island in the southern Mediterranean Sea named Lampedusa, about 70 miles by sea from Tunisia, much closer than to the mainland of Italy.
Since 2000, hundreds of thousands of migrants from Africa, Asia and the Middle East have set out from Tunisia in small boats, hoping to reach Lampedusa and set foot on European soil. Thousands have died in the attempt.
Dr Simone Panigada was patrolling the coast of Lampedusa, strapped into the bow of a small inflatable boat, holding a medieval weapon across his chest and searching for migrants – not from the south, but from the north.
A sudden flash of reflected sunlight alerted him that one was swimming in the water just ahead of his vessel. He signalled to Giancarlo Lauriano, at the helm, and the boat lurched forward, racing ahead at full speed. Panigada raised his weapon and fired.
The projectile arced across the water, striking his quarry with two sharpened points that buried into its flesh.
It succeeded in securing a barnacle-sized packet of electronics to the dorsal fin of the migrant – a fin whale that had previously been observed during the summer, feeding in the Ligurian Sea along the Italian coast.
The LIMPET (Low Impact Minimally Percutaneous Electronic Transmitter) tag would attempt to contact an Argos satellite every time the whale surfaced, and would transmit its position for the next six weeks.
Almost simultaneously Nino Pierantonio, Dr Panigada’s colleague at the Milan-based Tethys Research Institute, fired another crossbow. This launched a hollow-tipped arrow at the whale’s flank.
The arrow struck and fell into the water, cradling a small plug of skin and blubber for analysis of DNA and toxins. The whale reacted to both insults with a small twitch, as if stung by a mosquito, and returned to the business at hand.
That business was the ingestion of massive quantities of krill, which were swarming in sufficient density to stain the blue surface waters a shocking pink.
The krill, normally found hundreds of feet deep, were feeding at the surface due to massive upwellings that bring cold nutrient-rich water to the surface around Lampedusa during the first few months of each year.
THE UPWELLINGS RESULT from the interaction of deep currents with dramatic bottom topography. While the presence of fin whales in the northern Mediterranean during the summer has been known since ancient times, rumours of winter-feeding aggregations around Lampedusa were not confirmed until 2004.
Researchers found that the whales were not only feeding “out of season,” but were doing so right at the surface, and throughout the day. Fin whales in the Ligurian Sea feed mostly at night and at depth.
Around Lampedusa, the whales were also feeding in groups, possibly collaborating to herd prey – a behaviour not previously recorded in Mediterranean fin whales.
The question that most bedevilled Tethys founder Giuseppe Notarbartolo di Sciara was whether these whales belonged to a separate southern Mediterranean population, or were the same whales that his organisation was studying during the summer in the Ligurian Sea, in the region near the border of France and Italy.
The fin whale is one of the most mysterious and elusive large animals on the planet, and is, in many ways, an extreme oddity of the animal kingdom.
In nearly all vertebrates the left side of the body is a mirror image of the right side. Fin whales are a dramatic exception. The lower jaw on the left side is a typical whale grey, while on the right side it is brilliant white.
The right dorsal surface also has artistic swirls of creamy patterns known as a blaze and chevron, which are unique to each individual and allow Tethys researcher Margherita Zanardelli to photo-identify each whale.
Scientists speculate that the reflectivity of the white lower jaw might be used to startle and herd prey, but any functional advantage of the blaze and chevron is harder to conjecture.
FIN WHALES PUSH THE EXTREMES of the animal kingdom in speed, size and feeding ecology. They are the second-largest creatures on the planet (after blue whales), and could be the fastest swimmers in the ocean. Calculations predict a theoretical maximum of around 30mph, and Pierantonio believes he has seen one swim at least that fast.
Estimates of higher speeds achieved by billfish and dolphins are based on the animals jumping above water or riding boat wakes. The feeding dives of fin whales may also be the deepest of any baleen whale. They are estimated to plunge to nearly 600m in the Mediterranean in search of krill.
Fin whales do not merely swim along with mouth agape to filter plankton, as do right whales, but capture their prey of krill or small fish by lunging repeatedly at high speed, engulfing a volume of water that can be larger than the entire body of the whale prior to opening its mouth.
Each lunge requires rapid acceleration, and an enormous expenditure of energy. This was described as “one of the most extreme feeding methods among aquatic vertebrates” by researchers at the University of British Columbia.
To fuel the intense energetic demand of maintaining a huge body and operating it at high speed, it has been estimated that a fin whale must consume a metric ton of krill every day.
Fin whales can also maintain high swimming speeds over large distances when travelling from one area where food is present in sufficient concentration for them to feed to another such area.
This was illustrated by one of the two whales LIMPET-tagged by Panigada in March 2015. It swam from Lampedusa to the northern tip of Corsica, crossing the Mediterranean from south to north in five days. It averaged more than 100 miles a day while crossing some of the world’s busiest shipping lanes.
A second whale tagged the same day made a similar migration, confirming that the same whales feed seasonally on both sides of the Mediterranean. “The fog surrounding our understanding of fin-whale movements in the Mediterranean seems to be lifting to some extent,” said Notarbartolo di Sciara.
The dramatic results were more cause for concern than celebration, however. Ship strikes are the leading known cause of death in fin whales, and these whales swim close to the surface and come up to breathe regularly while migrating.
The confirmation of the Lampedusa area as an important feeding ground is also of concern because of the “exponential growth of fishing effort” in the region, according to the report submitted to the International Whaling Commission by Panigada and his colleagues.
Fin whales are classified as endangered worldwide. The Mediterranean population has never been targeted by commercial whaling, but there are serious threats from ship strikes, fishery interactions, chemical pollution, sound pollution and disturbance by whale-watching operations.
The Mediterranean fin whales constitute a genetically distinct sub-population that has been isolated from the North Atlantic population for 200,000 years. The Mediterranean whales rarely leave that sea except for short forays into the Atlantic just beyond the Strait of Gibraltar. Researchers can distinguish Med and Atlantic whales by the unique characteristics of their calls.
AFTER A LONG CAMPAIGN by the Tethys Institute, the Pelagos Sanctuary for Mediterranean Marine Mammals was created in 2002 by Italy, France, and Monaco. It was the world’s first Marine Protected Area (MPA) that is international, and the first that is mostly in pelagic waters.
The sanctuary covers almost 34,000sq miles, stretching from just off the French and Italian Rivieras almost to Sardinia’s north coast. It includes territorial waters of three nations, but much of it is in international waters or ABNJ (Areas Beyond National Jurisdiction).
With the Pelagos Sanctuary as an example, there is now a process in the UN to establish additional MPAs in ABNJ, which cover 40% of the earth’s surface.
The abundance of whales in this region was not recognised by scientists until Notarbartolo di Sciara began studying cetaceans there in the late 1980s.
Many divers still consider that “the Med is dead”. “That’s not true,” says Tethys associate Sylvan Oehen. “The Mediterranean is overfished for some species, but the primary productivity is still there, and it supports a lot of life!”
Photographer Danny Kessler was surprised and intrigued when he learned about the Tethys research while on holiday in Sardinia. He had assumed that the clear blue waters of the Med indicated a sterile environment, not realising that ocean giants were diving deep to use food resources hundreds to thousands of feet below the surface.
He was also amazed when Cetacean Sanctuary Project Director Sabina Airoldi showed him maps of seasonal upwellings, and he learned that the fleet-finned fin whales could dash hundreds of miles to get from one short-lived productive feeding area to another.
Kessler invited me to join him in an attempt to get the first high-quality underwater pictures of fin whales that would show the amazing length of the entire body. I realised that this would be a difficult endeavour, but it proved to be very, very difficult, even with the expert assistance of the Tethys scientists.
The researchers had assured us that fin whales would sometimes surface right next to their research vessel, and even rest there momentarily. However, even using a custom-welded 5m polecam, I was unsuccessful in obtaining underwater images from their high-gunwaled yacht Pelagos. We would have to enter the water to attempt the shots.
Those who have never attempted to put themselves within photographic range of a great whale might imagine that such a huge and mighty animal would have no fear of a relatively tiny creature, which it could dispatch to eternity with a mere swat of its tail.
On the contrary, most large whales are extremely skittish, and will avoid divers in the water, as well as boats.
BLUE AND SEI WHALES, bracketing the fin whale in size, tend to travel on straight paths, and can sometimes be intercepted if you place yourself well ahead of the whale and hope it doesn’t notice in time to turn.
Apart from the fact that whales rarely swim in straight lines when they’re feeding, fin whales are nothing like the blocky whale caricatures in public lore. They are long, slender creatures that resemble giant eels, and are almost as supple.
Baleen whales do not have echo-location capability, yet these master survivors were somehow able to detect and avoid us before we ever saw them.
If they did get within visual range, they were able to bend their amazingly flexible bodies and make tight turns to avoid coming within camera range.
If a whale avoided us twice, we knew we would have no chance. It was better to give up and avoid harassing the animal.
The high gunwales of Pelagos made it impractical to put divers in the water, so we had to hire an inflatable to try to drop us in the path of the whales.
This introduced another obstacle. While some of the whales seemed to accept the larger, slow-moving yacht, most would turn away from the outboard-powered inflatable. We had to get them accustomed to our presence gradually.
First we spent hours tracking them on Pelagos. Then we launched the inflatable, but kept it in the shadow of the yacht. Finally, we moved the smaller boat away from the mothership, and were rewarded with a whale surfacing right next to us.
All my underwater photo “keepers” from four weeks at sea are of this animal. We never found another “player.” Time after time we had to break off our efforts to avoid undue disturbance to the whales.
Counts of fin whales in the Sanctuary have been declining in recent years, but may simply reflect a movement into other parts of the Med. Tethys researchers have also been monitoring populations of sperm, Cuvier’s beaked and long-finned pilot whales; striped, common, Risso’s and bottlenose dolphins; giant devil rays; and sea-jellies.
Studies in collaboration with the Italian National Institute for Environmental Protection & Research and the International Whaling Commission are funded by the Italian Ministry of the Environment, and use aerial surveys to count the number of rays and cetaceans as well as loggerhead turtles, bluefin tuna and swordfish.
Cetaceans here as elsewhere face a variety of threats. However, the unique international structure of the Sanctuary poses great challenges to enacting regulations to manage those threats.
Instead, Tethys has been working with user groups such as ferry operators, whalewatch companies and fishermen to try to mitigate those threats. Most importantly, the research continues to refine our knowledge of the biological needs of these species, and how they are being affected by changing conditions in the environment.
Every summer Tethys opens research cruises to volunteers who both assist with the research and help to cover the cost of the expeditions. For more information, see www.tethys.org.