Krill are food for elephant seals and fur seals, squid, and silverfish. Krill are plucked from above by a great many seabirds, including Wilson’s storm petrels, southern fulmars, and snow and Antarctic petrels, which in turn get their food stolen in midair by scavenging skuas. Many penguin species, not just emperors, hunt for krill as they dive through the Southern Ocean.

Whales are another major group of krill consumers. Southern right whales and humpbacks, sei and fin whales all come to Antarctica to eat krill and replenish their energy stores. Minke whales skim along just under the sea ice, lunging dozens of times on each dive, swallowing down great mouthfuls of krill. A single blue whale, the species with the biggest mouth of all, can gulp 3.6 million krill every day.

Curiously misnamed, crabeater seals don’t in fact consume crabs but have the whale-like habit of straining krill from the sea. To do so, they evolved the most specialised teeth of any carnivore, with multiple curved cusps that interlock to act as a sieve. A crabeater seal swims through a shoal of krill, mouth open, then snaps its jaws shut and pushes out the seawater through its teeth, holding back the krill and then swallowing them.

No other ecosystem on earth relies so much on a single species. Even apex predators, such as orcas and leopard seals, are no more than one step away from krill when they chase after fish, squid, and penguins.

How all this will change as the climate crisis bears down is not an easy matter to get a handle on, especially as krill populations naturally fluctuate year by year. Even so, plenty of studies cast grim predictions for the future of krill because of their reliance on sea ice and their need for cold, productive waters. Female krill need to eat a lot during the summer to build up their body reserves and store enough energy to successfully spawn the following year. The way ecosystems are changing, female krill could soon struggle to get the food they need to see them through the year. It’s likely that individual krill will grow to less than half the size they are now. The total population of krill could shrink by a third by the end of the century. Add in the impacts of the ocean absorbing more carbon dioxide and becoming increasingly acidic, and Euphausia superba could collapse altogether in three hundred years or so.

Currently, enough krill swarm around Antarctica that there are no pressing concerns for their extinction. But as certain parts of Antarctica are showing, what matters is where exactly krill are at their most plentiful.

The term global warming can give the misleading impression that the whole planet is heating gradually by the same amount everywhere. Changes already taking place in the global climate are by no means uniform. The Antarctic Peninsula is one of the fastest-warming places on the planet. This thousand-mile finger of icy land and islands—which points towards Tierra del Fuego, South America’s southern tip—is the spinal column on the brain map of Antarctica. Since the 1950s, the air temperature here has risen by three degrees Celsius, and the surface seas by one degree. During a heatwave in February 2020, a new record for the Antarctic continent was set at the peninsula’s northern tip, where the air temperature reached 64.94 degrees Fahrenheit (normally, summer temperatures don’t rise more than a few degrees above freezing). It’s no great surprise that the sea ice here is rapidly melting, and krill populations are retreating polewards, tracking their icy habitat to the south. At the same time, two krill-eating penguin species that used to live all along the peninsula are now in drastic decline.

Adélie penguins are small and sleek, their whole heads black, as if dipped in paint, leaving a white-ringed eye. They’re easy to tell apart from their close relatives the chinstrap penguins, whose black cap appears to be held in place by a dark band secured neatly under the chin. Colonies of both species, which used to be noisy with thousands of nesting birds, are growing increasingly sparse and quiet. On several subantarctic islands north of the peninsula, chinstrap numbers are less than half what they were in the 1970s. Adélie colonies are similarly collapsing. The number coming to nest near the American Palmer research base has dropped by around 80 per cent.

Chinstrap and Adélie penguins are not at imminent risk of going extinct. Across the whole of Antarctica, there are between six and seven million birds of each species living in hundreds of colonies. In the more stable parts of Antarctica, including the Ross Sea, numbers of Adélies are still healthy; chinstrap colonies in parts of the South Orkney Islands are increasing in size. Even so, their dire status along the peninsula is worrying enough, in and of itself, and it’s an ominous sign of what could lie ahead.

Penguin experts don’t yet understand precisely what is going wrong with the peninsula’s chinstraps and Adélies. It must have something to do with the shifting ice and krill populations, particularly during the nesting season, when penguins rely on a nearby supply of krill to feed their chicks. If there aren’t enough krill in the neighbourhood, then foraging adults are forced to set off on longer journeys to search for food, and they risk leaving their chicks to go hungry for too long.

Further complicating matters is the fact that whales, seabirds, seals, squid, and penguins aren’t the only ones hunting for krill. Now humans are too. The immense biomass of krill around Antarctica has proven too tempting for industrialists to resist. Factory ships, notably from Norway and China, head south to scoop up Antarctica’s krill. Specially designed trawl nets are lowered into the water and continuously scoop up krill shoals for weeks at a time, sending them straight to onboard processing plants. These krill will end up being eaten by domesticated animals. Most are mashed and turned into feed for salmon farms or into pet food.

Of all the krill shoaling around Antarctica, fisheries currently capture less than 1 per cent. People in favour of the industry consider this amount to be far too small to be of any ecological concern. The devil is in the granular details. If fishing vessels were to spread themselves out and gather their catches from across the entire range of krill, then these fisheries would likely have little impact. But that’s not what they do. Factory ships focus their attention on the peninsula, a krill hot spot that is the easiest and most profitable place to operate. Since 2000, the krill catch around the peninsula has tripled from 88,800 to 289,500 metric tons. By concentrating their effort, the ships may be competing with local wildlife trying to fill their bellies. For now, it’s difficult to disentangle the combined impacts of climate change and krill fishing because they’re happening in the same time and space. Indeed, as the ice is retreating south, the factory ships are also motoring farther south to access newly exposed regions of previously untouched sea.

Rather than industrial fisheries exploiting those waters, another option is to leave them alone. The organisation that regulates fishing around Antarctica, the Commission for the Conservation of Antarctic Marine Living Resources, has pledged to set up marine reserves to protect key parts of the Southern Ocean. At the time of writing, two such reserves exist. One is around the South Orkney Islands, which lie hundreds of miles north of the peninsula, and a second is on the other side of the continent, in the Ross Sea, where Apsley Cherry-Garrard went to find emperor penguin eggs. Since 2018, experts from Argentina and Chile have been leading a proposal to set up a third protected zone in the seas along the western coast of the Antarctic Peninsula. The safeguarding of these waters from exploitation would give krill and all the wildlife that depend on them as good a chance as possible of weathering the climate crisis. It would prioritise the Southern Ocean’s biodiversity over directing profits to the pet-food and fishmeal industries. So far, through several rounds of negotiations at the commission, plans to protect the peninsula’s waters have been rejected.

Even as sea ice and krill populations continue to rapidly decline, not all Antarctic species will suffer right away or to the same extent. Some will cope more easily than others. Gentoo penguins are already doing much better than their close relatives the Adélies and chinstraps. Similar in appearance to their sister species, except with a red beak, black head, and white band between the eyes, gentoo penguins live on the Antarctic Peninsula and on offshore islands, although not around the perimeter of the Antarctic continent. Their entire population is increasing, especially along the peninsula, where they’re moving south and claiming new territories as the ice retreats. The gentoos’ success most likely comes down to their flexible diet—they don’t rely solely on krill—and they seem to prefer it when there is not so much ice around. Thanks to the gentoos’ more resilient and, one might say, less refined nature, Antarctica in a warming world should still be home to large numbers of at least one species of penguin.

Drawing up lists of the likely winners and losers is perhaps a pragmatic way of dealing with the climate crisis. Some people argue that conservation efforts should be focused on the likely winners, leaving us to search for ways to grieve for the species that won’t make it through the Anthropocene. It may come as some comfort to know that survivors will exist even in the most imperilled places, including in Antarctica and the Arctic, where other species depend, to differing extents, on the swiftly shrinking ice. Among the survivors will be plenty of generalists, the species best equipped to make do and carry on. They will take the place of the specialists that carve out exquisite niches, that depend on predictable seasonal timings or rely exclusively on another species that may also soon be gone. The Anthropocene will have less and less room for great evolutionary phenomena, the likes of crabeater seals with their unique, krill-straining teeth and emperor penguins with their bubble-making feather suits.

But still, it is too soon to consign those sensitive, more specialised species to the loser list. As the planet rushes past one degree of anthropogenic heating, there are locked-in changes that we can do very little to stop. But we do still have a chance to decide how much we will continue to heat the planet, and that very much matters. From this point forwards, every half degree of heating that can be avoided will make a critical difference for the future of all sorts of species and their endangered habitats.

If corporations and governments do nothing to decelerate the climate crisis, emperor penguins will dwindle within the lifetime of human babies now being born. Not long after 2100, the species will most likely be extinct—if not sooner. But this is not an unstoppable fate for these giant, ice-walking birds. There is still a chance to prevent them from becoming little more than memories of a species that people knowingly allowed to disappear.

Simulations of the future of Antarctica run by Stéphanie Jenouvrier and colleagues explore two alternative possible climate scenarios. If emissions can be reduced enough to keep global temperature rise this century to two degrees Celsius above preindustrial levels, then the outlook for emperor penguins will be distinctly improved. Instead of losing 80 per cent of emperor colonies, as would likely happen if humans carry on with business as usual, we can expect only around 31 per cent to collapse. Limit temperature rise to 1.5 degrees Celsius, and the number of lost colonies is even smaller, around 19 per cent. In that scenario, by century’s end the entire population would stabilise at a new, lower level. Emperor penguins would be a great deal rarer than they are today, and they would persist in only a few climate refuges in Antarctica where enough sea ice remains, but the species would still exist.

There is also a more nuanced story that emperor penguins will tell. They will become a visible, incremental barometer of the climate crisis. A lot of the world’s most endangered species will fade out without anyone tracking their decline or watching for the point in time when they are gone for good. Like the dodo, those ones will slip away before anyone realises they are no longer around. Extinctions in the ocean will be especially hard to prove and easy to overlook—given the vast nature of this liquid habitat, which contains plenty of places to hide—so that people can continue to wonder if certain species might still be out there, somewhere. Emperor penguins would be different because of their habit of hauling out onto the ice to rear their young. The entire breeding population leaves the sea at the same time and stands on the white ice, making it possible to count them year on year. The more that humans successfully limit carbon emissions and minimise future global heating, the more intact sea ice will remain, and the more emperor penguins there will still be. Scientists will be keeping an eye on them via spaceborne satellites and hoping to see that when another winter ends and the sun illuminates Antarctica once again, the emperors will still be there with their new chicks, waiting until they grow new feathers and can return to the sea and slip back out of sight.

a The magnetic south pole wanders about as the earth’s molten iron core swirls.

b The main types of algae that krill eat are diatoms, including those of the genus Nitzschia.

Chapter 4 Missing Angels

In the sixteenth century, when European explorers set sail for the Americas, many of them encountered big sharks for the first time. When they returned home, they brought with them new words for the huge, unfamiliar animals they had seen.

“Above all there is an infinite number of some very large fish that they call tiburones,” wrote Spanish monk and traveller Juan Gonzáles de Mendoza in 1585. The word tiburón originated in the indigenous language of the Kalina people from the coasts of South America, and it’s still in use in Spanish today. The English adopted a term that has hazier origins and more multiplicitous meanings. It seems nobody can quite decide on the true origins of the word shark.

Both words originally applied to large sharks, distinguishing them from the smaller cazón, or dogfish, which Europeans in medieval times knew from fishing in waters closer to shore. Venturing beyond the horizon, sailors came across various pelagic sharks—those that roam across open seas—and no doubt included plenty of oceanic whitetip sharks. These bold, inquisitive sharks swim at the surface but only over water that’s more than five hundred feet deep, and they have a strong habit of following ships. Anyone watching over the side of those medieval vessels would have spotted this shark’s tall, rounded dorsal and tail fins, and long pectorals, all speckled in white at the ends as if they had been clumsily dipped in bleach. Even in those early days of European exploration, it was obvious that the ocean was teeming with oceanic whitetip sharks.

Shift forwards to the twentieth century, and there were still huge populations of this species cruising across the planet, through every ocean basin except the Arctic Ocean and the Southern Ocean, where the waters are too cold for them. A 1969 book about sharks described oceanic whitetips as “extraordinarily abundant, perhaps the most abundant large animal, large being over 100 pounds, on the face of the earth.” The 1971 documentary Blue Water, White Death set out to capture great white sharks for the first time on underwater movie cameras. The bait was a dead sperm whale, shot with an explosive harpoon by a whaling ship off the coast of South Africa. Divers climbed inside a metal cage and had themselves lowered into the sea to see what animals showed up to scavenge the floating whale carcass. There were no great whites, but almost immediately, dozens of oceanic whitetip sharks appeared, swimming in circles, lunging in and biting off chunks of blubber. “There must be twenty tons of sharks down there,” one of the divers said after making his way back to the ship.

A decade later, oceanic whitetip sharks were still reported to be superabundant. A 1984 report named them as one of the world’s most numerous large marine animals. Since then, however, their situation has taken a dramatic turn for the worse.

For every hundred oceanic whitetip sharks that roamed the Pacific Ocean in the 1980s, fewer than five are alive today.^a In some places, young whitetips have become vanishingly rare, and over time mature individuals have been shrinking in size, which could mean females are having trouble reproducing; the smaller a mother shark, the smaller the energy reserves she can draw on, and the fewer offspring she produces. Data on the whitetips’ status aren’t available throughout their global range; the situation in the Indian Ocean is especially vague. But wherever there is good information, a similar story is being told. These large sharks that were once so plentiful are disappearing from the ocean. In 2019, experts at the International Union for the Conservation of Nature (IUCN) considered all the available facts and declared the oceanic whitetip shark to be Critically Endangered—the most imperilled category in the IUCN’s Red List of Threatened Species, a go-to guide to species endangerment.^b Whitetips face a high chance of going extinct globally, and they’re not the only ones. In total, more than one-third of all known shark species and their close relatives the skates and rays, collectively known as elasmobranchs, are threatened with extinction. They are the second most endangered group of animals on the planet after amphibians. Close to four hundred species of elasmobranchs face an uncertain future in the Anthropocene ocean.^c

Cautionary tales tell of once superabundant species that humans nevertheless managed to extirpate. Passenger pigeons are a classic example. When Europeans began to settle in North America in the sixteenth and seventeenth centuries, somewhere between three and five billion of these graceful pigeons were living in mixed hardwood forests in the east. Settlers told stories of enormous flocks blotting out the sun for hours and days as they passed overhead, of tree branches breaking off from the sheer weight of birds roosting in them, and of their droppings lying inches thick on the ground. That all came to an end when people cut down forests and hunted the pigeons as a source of cheap meat. By the turn of the twentieth century, there were no more passenger pigeons in the wild. On September 1, 1914, the very last passenger pigeon, named Martha after First Lady Martha Washington, died in the Cincinnati Zoo.

The lesson of the passenger pigeon is proving difficult to transfer underwater because the myth lingers on that the inexhaustible seas are too big and animals living there far too abundant for humans to put a dent in their populations. But as the oceanic whitetip sharks show, existing in huge numbers over vast tracts of ocean is not enough to make a species immune to human destruction.

The chief explanation for the whitetip shark’s precipitous decline is linked to the very same habit that first brought the species to the attention of European sailors. As the seas have filled up with fishing boats, more whitetips have been swimming up to investigate and getting hooked and killed on fishing lines. The same goes for dozens of other ocean-roaming shark species. Great hammerhead sharks, up to twenty feet long, with their distinctive tool-shaped headgear, and their slightly smaller relatives the scalloped hammerheads are both now Critically Endangered. Great white sharks are classified as Vulnerable to extinction globally and as Critically Endangered in European seas. Pelagic thresher sharks, which stun fish in schools by whipping their immensely long tails over their heads, are Endangered. So are shortfin and longfin mako sharks, which race through the ocean faster than any other sharks. In all, since the 1970s, the global abundance of oceanic sharks and rays has declined by 71 per cent.

To wipe out so many animals that used to occupy hundreds of millions of square miles of ocean might seem like an improbable feat for fishing vessels alone to achieve. And yet, mounting evidence shows that fishing pressure is easily high enough to explain these multiple vanishings. In the past few decades, humans have massively expanded and intensified industrial fishing to the point that the collapse of once-abundant shark populations became inevitable.

A series of technological innovations made this possible, beginning with the switch from wind-powered to fossil-fuelled ships. In the late nineteenth century, steam-powered trawlers began plying the ocean, to be replaced in the twentieth century by diesel ships, which were even faster, more powerful, and capable of hauling larger fishing gear through the water and up on deck. At-sea freezing facilities allowed fishers to preserve their catches, stay out longer, and venture farther from shore. Wartime technologies heightened industrial fishing powers, with advances in sonar, radar, and navigational tools making it safer to be at sea and easier to locate fish schools. And in the 1950s, the American chemical company DuPont invented a new type of fishing line made from a single, long nylon fibre that was strong, lightweight, and difficult for fish to see in the water. Monofilament lines swiftly became a favourite of fishers around the world and since the 1980s have been used to make longlines, the gear used most widely through the ocean and that catches the most sharks.

The principle behind longline fishing is straightforward. A vessel pays out a single line, often using a mechanical line shooter that propels it into the water faster than the boat speed so it has a chance to sink down. Fixed on the longline at regular intervals are shorter branch lines, or snoods. At the end of each snood is a palm-size metal hook with a chunk of fish or squid attached as bait. The line can be set at a chosen depth, for instance, to catch fish near the seabed, such as cod and hake. More commonly, floats are attached so that the line drifts near the surface and catches tuna, marlin, and swordfish. Radio beacons are attached so fishers can find the ends of the lines after they have soaked in the sea for anywhere from a few hours to as long as a day. Then a hydraulic winch pulls the longline back in, and crew on deck unhook the catch by hand.

The hauling-in process alone can take between ten and twenty hours, which gives an idea of the scale of these operations. In the US pelagic fleet, the average length of longline set by an individual vessel is twenty-eight miles. Many other fleets use lines more than twice as long.

Sharks snagged on longlines are often referred to as by-catch, because the prime targets of these fishing vessels are other animals such as tuna. Even so, sharks make up a major part of catches and are economically important for fishers, who commonly keep the sharks’ meat and cut off their fins to sell in the trade for shark-fin soup. The precise number of sharks killed this way is not well known because most catches go unreported, and fewer than one in twenty tuna longliners have independent observers on board monitoring the catches. When observers are stationed on longliners, they witness just how intensive the shark slaughter can be. In 2018, observers on a Spanish longliner operating south of the Cape Verde Islands saw each longline catching an average of 7.6 oceanic whitetip sharks and as many as 54. During three months of fishing, that single vessel caught 416 whitetips, half of them dead by the time they were hauled in. Together all these living and dead sharks weighed more than twenty metric tons, an order of magnitude higher than the official reports for all the longliners operating that year across the entire Atlantic.

Until recently, it’s been nigh on impossible to calculate the worldwide impact of longlining on sharks. The global fleet of longliners is an unwieldy mix of vessels, some big, some smaller, most operating far from shore way out of sight from land. Now, though, thanks to another technological advance, the full extent of longlining is coming into view, and with it a clearer idea of just how deadly this form of fishing is for sharks.

International maritime law requires all large vessels to carry an identification system that broadcasts their position via satellite every few seconds, so vessels can avoid crashing into each other. Now researchers are using the publicly available data to map fishing activity. Computer algorithms recognise the characteristic patterns made by different types of fishing vessels as they move across the ocean. Trawlers take a wandering path. Purse seiners stay for longer in one spot while they gather in their circular curtain of nets, like a giant’s drawstring purse. And longliners tend to draw narrow V shapes as they motor slowly in one direction when setting out their fishing line, then turn around and trace another straight course while hauling it back in.

One year’s worth of satellite positioning data from seventy thousand vessels^d showed they collectively fished for forty million hours and covered more than 285 million miles—the same distance one would cover travelling to the moon and back six hundred times. In that year, 2016, more than half of the world’s ocean was industrially fished.^e That’s over four times the global area of agricultural land.

Longliners alone operate over at least 45 per cent of the ocean. They lace lethal lines throughout the territories of pelagic sharks, as revealed by thousands of sharks with their own identification systems in the form of satellite transmitter tags that scientists clip onto their dorsal fins. Pelagic sharks cruise immense distances through the high seas; one tagged oceanic whitetip shark swam four thousand miles in three months, all the way across the Indian Ocean. These species tend to occupy particular parts of the ocean where they feed and breed, such as a hot spot off the coast of California where great white sharks congregate, and many of these places are intensively fished. Combining satellite data from fishing vessels and tagged sharks, researchers have calculated how much the two overlap in space and time. Overall, pelagic sharks are forced to share one-quarter of their ocean space with industrial longliners. For some species the intrusion is much higher. During an average month in the North Atlantic, 63 per cent of the shortfin mako shark’s domain falls under the footprint of longliners.

There are no accurate figures for the total number of sharks that industrial fisheries kill every year. The best available estimate for the annual global death toll ranges between 63 and 273 million sharks. Many more sharks are dying off the record. Still, the devastation that longlines cause is plain to see from the slaughter that a single vessel can inflict—and from the global dominance of the longlining industry. Unchecked industrial fishing undoubtedly has the power to empty the ocean of pelagic sharks. These magnificent animals that were once so abundant now have very few places left to hide.

Many other types of sharks are at risk of going extinct, not just the sleek, torpedo-shaped animals sliding across the wide, open ocean that are getting hammered by industrial fisheries. These others, often less well known and hidden away, face threats from smaller-scale coastal fisheries and loss of their habitats.

Daggernose sharks weave their way through mangrove forests at the mouth of the Amazon River and along the South American coast. They have tiny eyes and rely on electrosensory perception in their flattened, triangular snouts to detect twitching prey in the murk. They don’t see the fine-mesh gill nets fishers set to catch mackerel until it’s too late. In recent years, the number of daggernose sharks has collapsed.

There are endangered zebra sharks and catsharks, weasel sharks and nurse sharks. Night sharks have big eyes, all the better for seeing in the dark depths, two thousand feet down, where they spend their days before swimming to the surface in shoals at night, when fisheries most commonly catch them.

The puffadder shyshark lives on coasts around the tip of South Africa. They are small and slender, brown with rusty orange saddles resembling the markings on their namesake, the puffadder snake. When disturbed, these sharks curl up in a tight circle and hide their eyes with their tails. They’re at risk partly due to their small native range, which is getting even smaller as the ocean warms and the shysharks are being forced southwards, but for this coastal species, the Cape of Good Hope is a dead end. They’re getting stuck in a climate trap.

Many skates and rays, the sharks’ close relatives, are also highly endangered. Giant butterfly rays look as if they’ve been flattened by a steamroller until they are eight feet across, making them all too easy to catch in fishing nets. Diamond-shaped flapper skates, nicknamed the manta rays of the North Atlantic, likewise suffer for their size; from the moment they hatch from their foot-long egg cases, the newborns are at risk of getting snagged in fishing nets. Wedgefish are sharklike rays that look as if they were made by stitching the tail of a regular shark onto the body of a stingray. Like sharks, wedgefish have fins that are highly valued in the soup-fin trade and command some of the highest prices; as a consequence of intensive fishing, they are now Critically Endangered.

All these elasmobranchs are struggling in the Anthropocene because the ocean is so intensively fished, a situation made worse by the fact that they tend to share a certain pace of life that puts them in jeopardy. Before humans came along, elasmobranchs were used to living in an ocean where they were rarely hunted and eaten. Usually, they were the ones doing the eating, and they evolved to be predators playing the long game. Sharks don’t sprint through life at a hectic biological pace, unlike sardines or mackerel, which hurry to grow up fast and produce copious numbers of offspring because at any moment they could be eaten by something else. Many fast-living fish can have their whole lives done and dusted while sharks are still taking their sweet time to reach maturity. Female oceanic whitetip sharks start pupping in their teens, flapper skates in their twenties. Greenland sharks take it to an extreme and don’t start reproducing until way past their hundredth birthday.

When sharks and rays are finally ready to begin reproducing, things still happen at a slow pace. Female sharks are typically pregnant for a year or more; shortfin makos give birth after a year and a half, basking sharks after two and a half. Female greeneye spurdogs, which gaze through the deep waters off Australia with dazzling emerald eyes, are pregnant for between thirty-one and thirty-four months, one of the longest recorded gestations of any animal.

Egg-laying elasmobranchs also have a leisurely start in life. Small spotted catsharks from the coasts of Europe entwine tendrils of their egg cases among seaweeds and seagrasses, leaving the embryonic pups to feed off yolk for up to eleven months before they hatch. In 2019, an angler off Scotland caught a female flapper skate, and before there was time to put her back in the sea alive, the shock caused her to prematurely lay an egg on the boat’s deck. Luckily, the pup inside was at a late enough stage of development that it survived, and scientists at a nearby marine research station took good care of the egg case. Eventually, after 534 days, the eleven-inch male hatchling finally wriggled out of his egg case, wrapped up in his wings like a burrito. He was the first flapper skate born in captivity, and after swimming test laps of his aquarium tank, he was released into the sea.

Elasmobranchs generally pour a lot of time and energy into producing a small number of big babies, bestowing each one with as good a chance as possible of surviving in the wild. Oceanic whitetip sharks give birth to six pups, on average, only once every other year. After nearly three years of pregnancy, greeneye spurdog females have between four and fifteen pups. Blue sharks push the boat out and give birth annually to fifty and sometimes more than a hundred pups, but generally, sharks produce no more than a few dozen offspring in a year.