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Young Reader's World

A Whale of a Storm - Adapted from a story by Anna McKibbin and photographed by Anna McKibbin
"Wmmff! Smell that fresh air!" That thought might be in the mind of this humpback whale as it breaches the waters of the Arabian Sea. Whales have been known to breach continuously for 90 minutes, making as many as 100 leaps in a row.

As we cling to the sides of our small rubber boat bouncing around on a sea of foam, we finally find what we’ve been seeking. No, we aren’t shipwrecked sailors searching for land. We are marine biologists on the lookout for whales in the Arabian Sea, off the coast of Oman. Suddenly, a leviathan heaves itself out of the water and crashes back down again, creating a wave that threatens to sink our boat. Then it slaps its tail and long fins on the water’s surface and sends up sheets of fishy spray—forcing us to shield our cameras. Finally, exhausted by its efforts, the creature lifts its tail and slides noiselessly back into the deep.

Omani and international volunteers in 2000 founded the Oman Whale and Dolphin Research Group, which counts and tracks marine mammals through the waters off the southern Arabian Peninsula.
"What kind of whale is that?" wonders a member of the Oman Whale and Dolphin Research Group. Founded by Omani and international volunteers in 2000, the group tracks marine mammals through the waters off the southern Arabian Peninsula.

We excitedly compare notes, trying to estimate the whale’s vital statistics. Such aerobics would be impressive if executed by a half-ton trained sea lion, but this is a humpbacked whale, some 12 meters (39') long and with a likely weight of around 35 tons. We’re about to restart our engines when an unearthly noise shakes our boat. It sounds like a deep chainsaw, then sweeps up to a shrill chimpanzee whoop. We drop our underwater microphone over the side and record the sound. Our whale is singing, a noise created by forcing air through massive air cavities in its head. Only male humpbacks sing, and they do it only during the breeding season. We’re not sure whether this is to discourage rivals or to attract a mate—perhaps it’s both. To us, it doesn’t sound like much of a love song, but it could help us understand how this whale is related to other whales that inhabit waters farther south.

You may not think that the Arabian Sea is home to an abundance of marine life, but our team from the Oman Whale and Dolphin Research Group has been very busy indeed. We’re spending a month on an annual field trip to the remote Hallaniyat Islands, 100 kilometers (62 miles) off Oman’s southern province of Dhofar. We hope the trip will help us understand more about the mammals living in these waters. It’s slow and painstaking work, and we’re using every research method at our disposal, including recording whale songs and taking DNA samples. Our transport is a 28-meter (93') oceangoing sailing dhow. Her slow speed is ideal for our purposes, and she comes equipped with a small inflatable boat that enables us to get close to any action, provided, that is, we can find some animals to study.

Sometimes it is difficult to find the whales! They’re big, but the ocean is a whole lot bigger. We search in areas where we know they might feed. That’s why we chose this particular location. Beneath us are underwater cliffs where the seabed plunges from a few hundred meters’ depth to more than a thousand (3250'). These are prime hunting grounds for squid and a good place to find sperm whales­—the squid’s most fearsome predators.

With a span that can be as much as five meters (16'), the flukes of a blue whale are caught by the camera before slipping below the surface.
The flukes of a blue whale stand out in sharp contrast to the distant mountains of Oman, just before it slips into the depths.

Soon our efforts are more successful than we could have hoped. In front of our boat we see a group of 50 sperm whales. These giants of the deep may look gentle but they are the world’s largest predators. They are capable of diving to depths of 2000 meters (6500'), where they stun squid with sonic clicks created in their enormous blunt heads. Now they are floating on top of the water, enjoying the bright sun, and taking turns sending up spouts of water. Then, one by one, each lifts its tail for another dive.

We record our encounters on sighting sheets, and the stack of them attached to my clipboard offers proof of our action-packed week: 3000 long-beaked common dolphins; smaller groups of Rissos dolphins; a secretive beaked whale, glimpsed so briefly that the exact species can’t be confirmed; four rare blue whales, each the length of two London buses, frolicking just offshore; and finally, three lone humpbacks. The humpbacks lure us in with their siren songs and allow us close enough to get a shot at them with our crossbow and biopsy dart. It’s a tricky operation, but worth the effort: The dart’s hollow tip collects genetic material invaluable to our work here.

We are happy to know that marine life in the Arabian Sea is flourishing, but we are also a little puzzled. These tropical waters are crystal clear and show no sign of the green algae generally needed to support a mass of marine life. So, where is the food coming from? The answer lies thousands of kilometers to the east.

During the summer months, temperatures in Oman’s capital, Muscat, climb to a sweltering 50 degrees Celsius (122° F). But farther south, the climate is very different. From the spring equinox through summer, warming air over southern Asia creates a powerful weather system known as the southwest monsoon. Rain-filled mists transform the dusty landscape into a lush garden, while winds whip the sea into a frenzy of foam.

Whales aren't the only mammals that live and breed in the Arabian Sea. Here, a common dolphin calf leaps alongside an adult.
Whales aren't the only mammals that live and breed in the Arabian Sea. Here, a common dolphin calf leaps alongside an adult.

During the monsoon, known locally as the khareef (“the time of ample rain”), fishermen pull their boats high up the beach and tend to their nets. While these storms prevent them from putting out to sea, they are vital to the following year’s catch. “The strong winds stir cold, nutrient-rich water up from the deep. It kick-starts the entire food chain,” says Fergus Kennedy, a marine biologist working with our team.

Humpback and blue whales are baleen whales. This means that, despite their huge size, they feed exclusively on small fish and crustaceans. They filter these creatures from the seawater using comb-like rows of springy, bristle-edged plates in their mouths called baleen, or whalebone. Scientists used to think these whales migrated twice a year to find the vast quantities of food they need to sustain themselves. That is, they left the warm winter breeding grounds of the tropics to converge on summer feeding grounds at the North and South poles. By all rights, then, we should only expect to see whales here in the winter months—yet, we were seeing them year-round. Why weren’t these whales migrating?

“Oman is in the northern hemisphere, and you’d therefore expect Oman humpbacks to spend the northern hemisphere’s summer in the Arctic,” explains Gianna Minton, another team member. “However, one look at a world map shows the difficulties involved in that sea trip.” The route to the Arctic from the Arabian Sea is entirely barred by the African and Asian land masses. However, the route to the other pole—the Antarctic—is clear. Could the whales be making the longer round-trip to feed there instead?

Given that whaling killed so many of these enormous creatures in past decades, it is ironic that much of our knowledge of these animals comes from data recorded by those involved in the whaling industry. The catch data published by countries that often hunted whales in the Arabian Sea, such as the former Soviet Union, provided the key to unlocking what has been called the “Arabian enigma.” Minton explains that around half the female humpbacks caught by the Soviets were pregnant, and that “the state of development of the calves suggested that the humpbacks were breeding here between January and May. It’s what we’d expect from a northern-hemisphere population, but it meant that they couldn’t be traveling to the Antarctic to feed. By the time they’d finished calving, it would be the southern-hemisphere winter.”

Analyzing whale DNA can provide basic information such as gender, and it can also help explain the relationship between populations of whales. Researchers gather genetic material using a crossbow.
Whale DNA can provide such basic information as gender. It can also help explain the relationship between populations of whales. In this photo, a researcher prepares to gather genetic material with a crossbow and a hollow-tipped biopsy dart.

Adding the Soviet data to our evidence of year-round sightings seemed to suggest only one conclusion: The whales were relying on the monsoons to “kick-start” the food chain and provide them with the nourishment needed to sustain them here for 12 months of the year. They weren’t migrating at all!

The results from our other research methods, including DNA analysis, point to the same conclusion. Humpback whales within any given geographic area tend to sing the same song, and this can vary greatly from one population to another. The songs of Oman humpbacks, however, have little in common with nearby populations off the east coast of Africa. This fact strongly suggests that the two populations have not come into contact with each other.

While the whales may stay in the waters off Dhofar year-round, we cannot. The winds are beginning to pick up, signaling the start of the khareef. We pack up our equipment and prepare to return to Muscat. We’d like to stay longer, but we know that the gales that evict us from the sea will sustain these leviathans until we return again.


Leviathan is a term used to describe a monstrous sea creature.

Biopsy darts are designed to collect a tissue sample from an animal when you have to do it from a distance.

An enigma is a puzzling or unexplainable situation.

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Anna McKibbin is a writer and photographer focusing on natural history and the environment. She is a trustee of the Indian Ocean Research and Conservation Association, a non-profit committed to the conservation of natural resources. She can be reached at [email protected].



This lesson correlates to the following national standards for world history and language arts, established by MCREL at http://www.mcrel.org/: