The Extinct Wolves of the Falklands
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Falkland Islands Wolf
(Dusicyon australis)
The story of the wolves of the Falkland Islands is one of mystery, a mystery that perplexed not only Charles Darwin when he visited the islands in 1833 and again in 1834, but also generations of naturalists since. Confused by what process would allow the Falkland Island wolves to colonize these islands but not a single other terrestrial mammal. Just how did a mammal of this size, probably as large as 20 kg (44 lbs), make it to islands isolated some 480 km (300 miles) east of the mainland of Patagonia? Numerous theories were proposed over the years. Some believed that the wolf was once a domesticated animal brought to the islands by ancient humans. Others thought a group of these wolves were somehow transported by ice or logs that swept them to the islands. Certainly, finding a population of canines on an isolated, windswept archipelago hundreds of miles from the nearest continent was unique in history. Of course, large mammals rarely inhabit islands simply because they lack a good way to get there, but apparently no one told these wolves about that.
Genetic studies of the few specimens that remain in the world's natural history museums may have shed some light on the problem. The genetic relationship of the Falklands wolves to other canines was a mystery in itself, but one that had the possibility of providing information on the origins of these unique creatures. Earlier studies had shown that their closest living relative was the maned wolf (Chrysocyon brachyurus) of South America. However, the maned wolves and the wolves of the Falklands are separated by nearly 7 million years of evolution, leaving the specific origins of D. australis elusive. In 2013, researchers were able to determine the wolves’ closest relative was an extinct canine from the mainland called Dusicyon avus. More importantly for the Falkland wolves’ origin story, they were able to determine that the Falkland wolves split off from Dusicyon avus sometime around 16,000 years ago. This date is important for two reasons. One, it likely eliminates the possibility that humans introduced the Falklands wolves, and two, it may explain how they came to reside there. The date closely aligns with a glacial peak that dramatically lowered sea levels compared to today. This left a narrow and shallow 20-km-wide straight between the island and the mainland. Freezing of the shallow strait in the winter likely allowed the Falkland wolves’ ancestors to reach the islands. When temperatures and sea levels rose, it trapped the wolves' ancestors on the islands and eventually gave rise to the wolves that Darwin observed in 1833. Why no other mammal made it this way is unknown, but there was probably little incentive for them to follow the ice bridge to the islands, whereas the plucky predators came as a result of a food search, where they discovered an abundance of seabirds and marine mammals.
The Falkland Island wolf is not only known for its surprising existence, but unfortunately, it is now known for being the only canine known to suffer an extinction in modern times. Commonly called wolves, they were more like foxes in appearance and behavior. Darwin commonly referred to them as foxes and described them as possessing a wolf-like head but otherwise appearing like a tall, stout fox. They were about the size of a North American coyote, but with shorter legs and a more substantial build. These solitary hunters were found throughout the islands and primarily fed on penguins and other birds, as well as visiting pinnipeds. It seems they would eat nearly anything, including fish, crabs, and even insects. Unfortunately, a detailed study of the wolves never occurred. Nothing is known of their reproductive habits or offspring. It does appear as though they used burrows commandeered from penguins nesting on the islands.
Their original population is also unknown. Europeans first saw them as early as 1690, but the island continued to be uninhabited until 1765. The species was not formally described until 1792, but by this time it was already suffering from the pressure of humans. As early as the first expedition to claim the Falklands in 1765, the wolves were being killed, and five were shot almost immediately after the expedition made landfall. According to Darwin, by the time he visited in the 1830s, the wolf population had already been significantly reduced. Unfortunately, the Falklands wolves had little fear of humans, making them easy to approach and kill. Many were taken for the fur trade, and the killing of the wolves only increased as the islands became ever more populated with sheep. By the 1860s, large commercial operations raising sheep were established on the islands and quickly became the leading industry, and, threat or not, the wolves were eliminated to protect the sheep. The last Falkland Islands wolf was killed in 1876.
The demise of the wolves of the Falkland Islands, disappointing as it may be, is not surprising. Humans have a longstanding tradition of eliminating predators wherever they go. While animals like the gray wolf (Canis lupus) were widespread enough to avoid complete extinction, even under heavy persecution, the wolves of the Falklands could not avoid the takeover of their islands by humans. Seen as a threat to man and his assets, with the added bonus of having a useful fur coat, the human inhabitants of the Falklands had no qualms about killing these animals, and they did just that until they were no more. Just as unfortunate as the historical persecution of wolves and other predators is that the common attitude toward them has changed little since these wolves' extermination.
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