ELEPHANT BIRD
When was it declared extinct?
It is unknown when the elephant bird became extinct, but it may have survived. until the late eighteenth or early nineteenth century.
Where did it spend its time?
The elephant bird can only be found on the island of Madagascar.
(Elephant Bird—The largest elephant bird species weighed approximately 450 kg.)
Elephant birds were among the heaviest birds ever known. Following the extinction of the last dinosaurs 65 million years ago, the mighty reptiles that had dominated the earth for more than 160 million years gave rise to a plethora of new species, some of which gave rise to giants such as the elephant bird. In their general appearance, elephant birds were similar to the flightless birds called "ratites" with which we are familiar today, such as the emu (Dromaius novaehollandiae), ostrich (Struthio camelus), rhea (Rhea sp.), cassowary's (Casuarius sp.), and kiwi (Apteryx sp.); however, the biggest elephant bird, Aepyornis maximums, was enormous.
It stood about 3 m tall and weighed around 450 kg (the giant moa of New Zealand was taller but far behind the elephant bird in terms of bulk—moa are discussed later in this chapter). Because there were few large predators on the island of Madagascar, and the elephant birds' ancestors had no need to fly, this ability was gradually lost. After being grounded, these birds evolved into land-bound animals. Their skeletons show that they had powerful legs and walked around Madagascar on their large feet. The wings were reduced to tiny structures that were most likely hidden beneath the bird's plumage. The large and specially modified chest bone (keellike sternum) found in most birds, which serves as an attachment for the wing muscles, had all but disappeared in these birds.
We don't know what the elephant birds ate, but the shape of their bill suggests they weren't carnivorous. Some people believe that certain Madagascar plants, which are now extremely rare, relied on elephant birds to disperse their seeds. These large birds' digestive systems were perfectly suited to breaking down the tough outer skins of these seeds. Some were digested, but others passed through the bird unharmed and ready for germination.
The elephant bird remains discovered so far allow us to piece together a picture of how this extinct animal lived. The bird's eggs are the most intriguing remains. Some have been discovered intact, and they are enormous—the largest single cells ever discovered. With a circumference of about 1 m and a length of more than 30 cm, they are roughly three times larger than the largest dinosaur eggs. One of these eggs had roughly the same amount of yolk and white as 200 chicken eggs. These massive shelled elephant bird relics are occasionally discovered in the fields of Madagascan farmers, and one is even known to contain a fossilised embryo.
Experts disagree on the number of elephant bird species that once lived in Madagascar, but it is possible that Madagascar supported several species of these large birds. The elephant birds were a successful group of animals on their island, surrounded by abundant food and few animals to fear, especially when fully grown. Then, around 2000 years ago, humans from Africa, Indonesia, and the islands surrounding Australia arrived in this remote land rich in natural treasures. Humans are one thing on their own, but thousands of years ago, humans did not travel alone—they brought their domestic animals with them. The elephant birds have never seen a human in their 60 million years of evolution, and they would not have recognized them as dangerous. The elephant birds, on the other hand, were viewed as a plentiful source of food by humans. Hunting had a devastating impact on the populations of these massive birds. Because they evolved in the absence of predation, they most likely reproduced slowly. To make matters worse, the humans' animals—pigs, dogs, rats, and so on—made quick work of the elephant bird's eggs. Other introduced animals, such as chickens, could have carried diseases to which these massive birds were never exposed. With no natural immunity to these pathogens, epidemics could have decimated elephant bird populations, which were already under stress from hunting and egg predation. Climate change may have contributed to Madagascar's drying out, which may have impacted the populations of these magnificent birds. The actual extinction timeline for elephant birds is unknown, but many experts believe that the last of these magnificent birds died before 1600.
The tools we have for ageing ancient material are constantly improving, and some recent estimates place the disappearance of these birds in the nineteenth century. Although some stragglers may have survived until recently, we can be certain that no elephant birds exist today.
• Madagascar was once a part of Africa, but the tectonic forces of continental drift rafted it away from the African mainland and into the Indian Ocean over millions of years. The island's animal inhabitants evolved in isolation, producing animal and plant species that were very different from those found elsewhere. Although the elephant birds are all extinct, Madagascar still has many other unique animals, the most notable of which are lemurs.
• The elephant bird has long been shrouded in legend and myth. The great explorer Marco Polo recounted tales of a huge bird of prey that could carry an elephant in its huge talons in the thirteenth century. The stories of this bird, known as the roc or rukh, convinced sailors who visited Madagascar and saw elephant bird eggs that the island was home to this massive raptor. This is possibly where the name "elephant bird" originated, and it appears to have stuck, even after Europeans discovered that the elephant bird was actually a giant ostrich.
• The elephant bird has long been remembered in the stories and histories of some of Madagascar's indigenous people (Malagasy). Elephant birds are described as gentle giants in these stories. Although these accounts are prone to exaggeration, they provide some insight into what the living elephant bird might have been like.
STELLER’S SEA COW
When was it declared extinct?
It became extinct in 1768, though it is possible that the species survived for a few more years.
Where did it spend its time?
Some of the last populations of Steller's sea cow were known. islands in the Bering Sea, just off the coast of Kamchatka.
(Steller's Sea Cow—At least 8 m long, Steller's sea cow was the largest marine animal other than whales, and it is the largest animal to have gone extinct in recent history.)
The St. Peter, captained by Vitus Bering, set sail from Kamchatka in 1741. The mission was to discover an eastern route to North America. On board was Georg Wilhelm Steller, a 32-year-old German who worked as the ship's official mineralogist. Steller was also a physician and a skilled naturalist. His voyage through the Bering Sea on the ship would be remarkable, and he would make numerous zoological discoveries. Steller meticulously documented everything he saw, and the majority of what we know about Steller's sea cow comes from the journal entries he and a crewmate, Sven Waxell, kept.
The sea cows were spotted near Bering and Copper Islands, where they could be seen swimming among and feeding on the vast kelp forests that grew in the shallows around these islands. Steller's observations provide information about how this animal lived and what it looked like. Steller's sea cow was a massive creature and one of the largest to go extinct in recent history. It was related to dugongs and manatees, two unusual marine animals found in tropical rivers, estuaries, and shallow marine habitats all over the world, but it was much larger. Adults could grow to be around 8 m tall, with a weight of more than 4,000 kg—possibly more than 8,000 kg. They were gentle creatures that appeared to spend their time grazing on kelp and snoozing, leaving large mounds of the seaweed washed up on the shore. They had a bony ridge in their upper and lower jaws to grind the fibrous algae, and their forelimbs were stout flippers that they could use to provide purchase on the rocky seabed when feeding in the very shallow coastal water. The skin of the animals was rugged, thick, and black, and Steller compared it to the bark of an old tree. The flesh of Steller's sea cow was a valuable commodity to the crew of the St. Peter, who had been shipwrecked on Bering Island. Not only were these massive sea creatures slow and gentle, but they also lived in family groups and appeared to be very curious. Steller noticed them looking into the small boats of men carrying guns and spears to shoot and stab them. The injured animals were allowed to swim away in the hope that the surf and tide would bring them ashore, which was a very wasteful strategy. This was not always the case, and the dormant animal would simply die and washbasin. The animals that were landed were butchered, and while the flesh had to be boiled for a long time, it tasted very similar to beef. When the survivors of the St. Peter were rescued, along with barrels of Steller's sea cow meat, it wasn't long before whalers, fishermen, and hunters, drawn to the area for the abundance of wildlife, turned their attention to these gentle animals to feed them on their journeys. They coveted not only the meat and fat of this animal, but also the oil extracted from its blubber, which produced little smoke and odour when burned. The skin was used to make a variety of leather goods.
It has been suggested that even when Steller first observed the sea cow in 1741, it was already rare, with human hunting having reduced populations to a fraction of their former size over thousands of years. Indeed, bones and fossils show that this species lived along a large portion of the North Pacific coast, from Baja to northern Japan. Steller discovered the last populations of this magnificent animal, which had survived in a remote, inhospitable location. Because it was such a large animal, Steller's sea cow was almost certainly a slow breeder, making it even more vulnerable to the effects of overhunting. Whatever the population of this animal was like when it was discovered, we know it was extinct by 1768, 27 years after Steller described it. It is possible that a few people Individuals survived in the shallow waters of other Bering Sea islands, but a late-eighteenth-century expedition found no sea cows. Even today, some people hold out hope that Steller's sea cow has survived into the modern era, citing sightings around the Bering Sea islands. Unfortunately, such a large animal, which spent so much of its time on the surface, is unlikely to have escaped detection in an increasingly crowded world. Twenty-seventy years is an incredibly short time for an animal to be wiped out, demonstrating how ruthless humans can be in their extermination of other creatures.
• Except for the last species, all can still be seen today, but their populations all suffered greatly at the hands of hunters who flooded into the area after Bering's disastrous voyage. The spectacled cormorant, a large marine bird with a distinct aversion to flight, was last seen around 1850.
• In addition to the species that bear his name, Steller recorded other animals that have never been confirmed. One of these was the "sea ape," a marine animal with an unusual set of characteristics. It is impossible to know whether the sea ape and others are modern animals, but Steller's documented observational abilities leave us with the tantalizing possibility of other, as-yet unknown animals swimming in the cold but productive waters of the Bering Sea.
• In December 1741, the St. Peter was forced to seek refuge from the Bering Sea's atrocities on what became known as Bering Island. Vitus Bering and 28 of his crew died of scurvy on this island. The survivors, including Steller, made it through the winter, building a new vessel from the wreckage of the St. Peter and returning to Kamchatka. Back on land, Steller spent the next two years documenting the vast peninsula of Kamchatka's animals, plants, and geology. He was eventually asked to return to St. Petersburg, but died on the way due to an unknown fever.
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