The History of the Decline and Fall of the Great Auk
Introduction
The extinction of species has long captivated the curiosity of scientists and nature enthusiasts alike. Within the realm of vanished creatures, the great auk stands as a prominent figure. As the only flightless bird in the North Atlantic, the great auk (Pinguinus impennis) held a unique position as the largest member of the Alcidae family, commonly known as auks. Towering at an estimated height of 75-90cm and weighing around 5kg, this goose-sized seabird has left an indelible mark on our natural history (9, 14, 25).
Distinguished by various names such as 'The Great Auk,' 'Garefowl,' and 'Penguin,' the great auk's association with the latter term highlights an intriguing conflation. While flightless birds of the Southern Hemisphere now bear the name 'penguins,' it was originally applied to the auks. The wing musculature and skeletal structure of the great auk reveal its convergent evolution with the Spheniscidae penguins, emphasizing its role as a pursuit-diving bird adapted for a flightless existence (14, 33). As a unique species in the Northern Hemisphere, the great auk's extinction stands as one of the significant losses of the modern era.
However, is it accurate to label the great auk's demise as a strictly modern loss? While it is unquestionable that the species survived into the 19th century, its decline stretches back far beyond that timeframe. This essay aims to unravel the pattern of the great auk's decline throughout the Holocene, leading up to its final credible reports, and explore the probable cause of its extinction. As we delve into the historical accounts and scientific evidence, it becomes apparent that the great auk's extinction in the 1840s or 1850s was merely the culmination of a long decline.
Figure 1. Illustration of two great auks by famous artist John James Audubon from his book The Birds of America
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The Slow Decline of the Holocene
The great auk once enjoyed a vast geographic range, which is often underestimated when considering the species in the context of the modern period, the period from which our historical accounts derive. Nonetheless, from fossil and archaeological evidence, we can infer that the species extended almost as far south as the Tropic of Cancer in both the East and West Atlantic. In this section, we will delve into the distribution of the great auk, its recorded disappearance, and discover that while we typically perceive the eradication of the species as a modern phenomenon, the auks of the 18th and 19th centuries were merely a small relic of their original population.
Let's begin in the West Atlantic. There is ample evidence to suggest that the great auk once inhabited the entire Eastern seaboard of the United States and Canada, and this distribution seems to have been maintained until relatively recently. Pleistocene remains confirm the presence of the great auk in Massachusetts (8), Virginia (28), and likely many other locations. The southernmost recorded occurrence of a great auk in the western hemisphere is from Florida, where great auks have been found in several middens (layers of food scrap generated by humans). The age of these remains varies, but the most recent discovery was found within a stratum dating back to 1307 AD (2), while other remains have been dated to approximately 1000 BC (2). Despite the evident extensive range the great auk once inhabited in North America, there are no known records of the species being encountered in the southern part of the continent by the time Europeans arrived (6). The southernmost account during historic times is a tenuous sighting off the coast of North Carolina in 1762 (21), and otherwise, historical records of the bird in North America are limited to the Northeast.
A single pre-maxilla from the Middle Pleistocene of Bermuda establishes the species' presence there, although this fossil is the only one ever discovered on the island (20). Likewise, a single specimen from the Late Pleistocene is known from Madeira (20). However, it is possible that these may simply be the remains of stray birds or carcasses washed ashore (20), as no historical accounts of great auks are known from the discovery of these islands.
Across the Atlantic, there is a much better-documented record of the great auk and its historical decline prior to the modern era. A single recorded occurrence here in Africa is from Morocco at El Harhoura 2 Cave, where only a single individual is known from a single site on the Atlantic coast (3). More great auk remains have been found in nearby Southwest Europe, where both Pleistocene and Holocene bones have been retrieved along the Iberian coast, extending into the Mediterranean with remains from Southern France and even the coast of Italy (3). Nevertheless, great auks are relatively rare in this region, suggesting that it probably constituted sub-optimal habitat or lay far from any breeding colonies.
The absence of other remains makes it impossible to determine the exact time of extinction in Morocco, but the dating of the midden suggests the species survived in North Africa until at least 7000 years ago (3). Similarly, the great auk disappeared from the Mediterranean around the same time. Only along the Iberian coast do the remains seem to persist until about 4,000 years ago. A single site near Gijón on the North Spanish coast dates back to the Roman era, around the 4th century AD (3, 22).
Moving north along the European coast, France has relatively scarce records of great auks, though Holocene remains are attested along both the west and north coasts (3). Further north, we reach the Netherlands, where a few great auks have been found throughout the Holocene and Pleistocene (12), with the latest dating back to the Roman era, around the 2nd or 3rd century AD (7). In Southern England, great auk remains have also been associated with Roman-era settlements (15), and as we head northwards to Scotland, remains from the North of the mainland extend into the Iron Age (1). We will revisit the British Isles later as several small islands served as final holdouts for the great auk.
In Norway, there is a well-established record of great auk occurrences along the entire coast. A 2022 study by Hufthammer & Hufthammer investigated the age of almost 500 great auk bones retrieved in the country to establish a timeline of extinction. It was found that great auk occurrences in Southern Norway all date back to before 4000 years ago, after which they are assumed to have gone extinct. In Sweden, remains are primarily found along the west coast of the country, indicating that great auks were relatively rare in the Baltic and primarily ranged into Kattegat. This is further supported by an abundance of great auk material found in middens in Eastern Denmark (6). Like in Southern Norway, the Swedish and Danish remains of the great auk disappear around 4000 years ago (9). However, there is evidence to suggest that, although rare, great auks were found even in the Baltic Sea, with bones being discovered as far in as Gotland during the Stone Age (16). The most recent remains in Norway are dated to the 16th century AD, though calibration may change this estimate to the 11th century AD. Interestingly, great auk remains have been found as far northeast as Finnmark, marking their easternmost fossil occurrence (9). Furthermore, these remains from Finnmark represent smaller individuals compared to those found elsewhere in Norway, implying a separate population. Additionally, there are records of immature individuals, suggesting proximity to a breeding colony, although no such colony is known to have been present in the region.
The presence of great auks east of Finnmark, that is on the Russian north coast, is a subject of debate. While no reliable accounts are known from this region, a few pieces of evidence suggest their potential occurrence here in recent times. Firstly, an 1848 sighting in Kirkenes (which we will revisit later) took place only a few kilometers from the Russian border, suggesting a distribution likely ranging into the Kola Peninsula (30). A second piece of evidence for a Russian distribution comes from a great auk egg in a museum in Pavia, apparently sold to the museum by a Russian aristocrat whose name has been lost (27, 30). However, the origin of the egg from Russia cannot be guaranteed. A final possible piece of evidence is an account by the French explorer Pierre-Martin de La Martinière of an expedition aboard a Danish ship exploring the far north in 1653. Upon reaching Novaya Zemlya, La Martinière described an encounter with four natives, two of whom were wearing clothing fashioned from the skins of "penguins," a term often used for the great auk in French (30). However, this term was also used for other species of auks, and an illustration of the "penguin suits" by La Martinière shows relatively small skins (see Figure 2). The account may, therefore, refer to the Atlantic Puffin (Fratercula arctica), which is well-documented on the archipelago (30). The presence of the great auk along the Russian coast thus remains an open question, and although occurrences in the Kola Peninsula are likely, they remain unproven.
Figure 2. Illustration of two natives of Novaya Zemlya wearing ‘penguin suits’ by Pierre-Martin de La Martinière, published in 1671.
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What can we make of this gradual retraction of the range of the great auk? First and foremost, the evidence suggests a human cause for the decline. Regardless of location, great auk remains are primarily found within middens, indicating that they were a part of the diet of the peoples of Europe and America. At the edges of the great auk's range, these middens contain very few remains, as seen in Gotland and Morocco (3, 16), and probably represent individuals far from the breeding sites of the great auks. Unfortunately, we are unaware of the locations of pre-historic breeding sites, making it difficult to determine whether the retraction of the great auk's range signifies the abandonment of southerly breeding sites or simply natural selection against individuals straying far. Many great auk bones found in middens also bear cut and burn marks, providing strong evidence of human hunting (1, 2, 5, 6, 9). In Scotland, an analysis also clearly demonstrates a decline in great auk bones found in select middens over time. During the Mesolithic period, the birds make up a staggering 6% of all specimens, which remains somewhat stable until the Iron Age, where there is a rapid downturn. By the Viking Age, great auks only make up 0.07% of the specimens (1). Interestingly, the decrease in great auk remains coincides with an increase in gannet (Morus bassanus) remains. This suggests a scarcity driven by human exploitation, which was later replaced by a less choice species. A similar pattern is observed by Hufthammer & Hufthammer 2022 in Norway, where in the west and north of the country, populations seem to have remained relatively abundant until about 2000 years ago, where a marked decline in their relative abundance is observed in the archaeological record (9). A likely explanation for these trends is that great auks could tolerate low levels of hunting but failed to adapt to growing exploitation following population growth. This partly explains why the collapse of the species broadly occurred from south to north, with the sparsely populated areas of Scotland and Northern Norway seemingly supporting great auks until much later, and the remote islands of the North Atlantic serving as the final refuges. No other alternative to human exploitation provides a satisfying explanation, for example the climate in Europe during the middle and late Holocene only sees a gradual cooling which is relatively minor (31) and counter-intuitive to a South to North extinction pattern. But if there is doubt as to whether human exploitation is capable of eradicating great auk populations, the historical accounts from the modern period put them firmly to rest.
Figure 3. Map of the former range of the Great Auk, with geographic locations mentioned in text. Question marks denote areas where it is unclear if Great Auk once inhabited.
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The Final Push
By the dawn of the 19th century, the great auk had been reduced to just a few holdouts in the North Atlantic, where they could remain largely isolated. It is from these final remnants that we derive the bulk of our scientific accounts of the great auk and can gain the best understanding of their demise. So, where exactly did the last survivors manage to hold on?
Let's start in the West Atlantic. Reports suggest sightings in Labrador in the 17th century (5) and potentially off North Carolina in the 18th century, with suggested breeding colonies off Cape Cod and Cape Breton (6). However, the most prominent area for great auks was Newfoundland and its small offshore islands. Exploitation by European sailors is well-attested in this area, and multiple colonies are thought to have occurred on small islands, including one dubbed 'Penguin Island' due to the abundance of great auks. Initially, the limited number of sailors arriving at the close of the 15th century hunted what may have been sustainable numbers of the huge population present in the area. However, population growth, local food scarcity, and a growing market for great auk eggs and feathers in Boston and New York drove exploitation to catastrophic levels. By the 17th century, all but a single colony in North America had been wiped out. Funk Island, owing to its remoteness, held on. Nevertheless, even Funk Island was facing great auk population declines. Despite a ban on hunting in the 1780s by the governor of Newfoundland, exploitation persisted, and the last great auk individuals on Funk Island vanished in the early 19th century (5). There were several sightings in North America in the 1840s and 1850s. In 1852, there was a report of a single great auk from the banks of Newfoundland, witnessed by a Colonel who was well-versed in ornithology (5). Another dead bird was reported the following year in Trinity Bay, Newfoundland, and supposedly, a great auk was caught by a captain near Newfoundland in 1856. However, this last account is especially questionable since the ship sank soon thereafter with all hands lost and no corroboration was ever made (5). Regardless of the truth of these claims, the collapse of the Funk Island colony practically marked the end of the great auk in North America.
Moving across the Atlantic to the British Isles, there is evidence of the continued survival of the great auk into the 18th and 19th centuries at numerous locations. In the Hebrides archipelago, there is an account of the capture and killing of a great auk on the remote island of St. Kilda in 1840. Supposedly, once captured, the bird cried out, and this coincided with the arrival of a thunderstorm that trapped the captors at sea for days. Eventually, they concluded that the auk was, in fact, a witch and killed it (5, 6), according to the story (see figure 4). Regardless, great auks were reported on St. Kilda prior to this account, and despite the far-fetched nature of the story, a capture is certainly possible. In the Orkney archipelago in the East, the last known report of a pair of great auks is from 1812 when one specimen was captured on the Island of Papa Westray and sent to the London Natural History Museum (5). There is also evidence to suggest a late survival on the Isle of Man, with a bone discovered dating back to the 17th century (23), and eyewitness reports extend into the early 18th century (1). Southwards, off the coast of England, there are accounts of great auks on the Farne Islands in Northumberland until the 18th century. A few sightings in the 19th century describe great auks in the English Channel, but they are generally questioned by experts. Lending some credibility to these sightings is the account of a dead great auk found near Lundy in 1829 and an abnormally large egg found on the coast of Lundy Island in the 1830s (5, 13), which could suggest a small breeding population in the South of England. Great auks likely also bred on the islands of Scilly, though there is no evidence suggesting their late survival there (23). In Ireland, two specimens were recorded near Waterford harbour in 1834. Another specimen apparently washed ashore near the southern tip of the island in the early 1840s. Two great auks were possibly spotted in Belfast Bay in 1845, but the designation is uncertain (5). Given these accounts, a tentative extinction date in the British Isles can be set in the 1830s or 1840s, depending on the validity of the various reports put forward.
Figure 4. The killing of the last confirmed Great Auk on the island of St. Kilda in 1840. After the auk was captured by three sailors who intended to sell the bird, it supposedly conjured up a storm forcing the men to take refuge on the island for three days. Concluding that the bird was a witch the sailors clubbed it to death, marking the ignoble end of the species in Britian.
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A few accounts from the European mainland are also known from the 18th and 19th centuries, mostly from Scandinavia. One specimen was shot in Kiel Harbor, Germany, in 1790 (6). An old Swedish fisherman is reported to have allegedly spotted a great auk near Bohuslån in the early 19th century, and a dead great auk was reported to have washed up near Fredrikstad in Norway also sometime in the beginning of the 19th century (6). However, both these reports are typically viewed with doubt. One report from Norway appears much more credible. In 1848, four great auks were spotted near Kirkenes in Finnmark, Norway. The eyewitness could reportedly identify a great auk when shown a series of images of birds occurring in the region, and he was an experienced hunter familiar with species that could be confused with the great auk, such as the common loon (Gavia immer). Another point lending credibility to this report is that the birds apparently attempted to flee by swimming rather than flying, which would fit with great auk behaviour but not loons (5, 30). If true, this would mark one of the last and perhaps the eastern-most sighting of a great auk. These last sightings in Europe (if at all credible) are most likely vagrants, and for all intents and purposes, the great auk was extinct in mainland Europe by the dawn of the 19th century. A possible exception could be argued for Finnmark, as archaeological evidence suggests a breeding site in the region, but this has never been located (9).
It is worth asking why there were no efforts to protect the great auk in Europe and the British Isles, as there had been in Newfoundland. The scientific community at the time seemed to be under a misapprehension, suffering from shifting baseline syndrome. The consensus was that the great auk was a bird native to the far north of the Atlantic, and that occurrences in Britain and Europe represented the southern-most part of its range, but that populations still existed in the Arctic. Unfortunately, this was not the case, and the misapprehension was only clarified in the final years of the great auk when ornithologists went north in search of great auks and found only a few tiny populations remaining (5).
Although the great auks seemed to have lived in northerly latitudes, it appears to have been suboptimal habitat for them. Evidence presented by Hufthammer & Hufthammer 2022 demonstrates an archaeological record in Finnmark, and it is perhaps telling that the final credible eyewitness account is from there. However, human exploitation reached even these remote corners of the world. In Svalbard, only a single sighting is reported, and its validity is dubious (Grieve 1885; Gaskell 2000). In southern Greenland, there is ample evidence of great auks, and even a reported breeding site near Sisimut used in the 18th century, although this population was relatively small. Supposedly, exploitation of great auks in Greenland goes back thousands of years, but increased harvesting by European settlers seems to have surpassed sustainable levels, and in 1815, the last known individual from Greenland was killed (5, 17). There was purportedly a sighting from Greenland either in 1859 or 1867, depending on sources, as a native shot a bird unfamiliar to him, which fit the description of a great auk. However, this source is highly contentious, but if true, it would probably mark the last ever sighting of a great auk (5).
It is unclear when the great auk disappeared from the Faroe Islands, but several naturalists visiting in the mid-1800s noted that older locals mentioned observing the birds and, in one case, killing one, tentatively placing the last sightings around 1800. One man reportedly caught one in 1808 (5). The Shetland Islands altogether lack accounts of great auks in modern times (5, 6).
This brings us to what is conventionally considered the last refuge of the great auk, or at least its final breeding grounds—Iceland. Due to its remoteness and low population density, the hunting pressure on Iceland was probably less severe than in most other places within the great auk's range, allowing it to retain breeding colonies into the 19th century. However, by the 18th century, great fowling expeditions were being carried out, heavily depleting the populations of great auks in the area. It is reported that the Icelandic population was particularly fond of great auk eggs (5). In 1813, during the Napoleonic Wars, a Danish ship raided a great auk colony off the coast of the Reykjanes Peninsula in Iceland to feed the inhabitants of the Faroe Islands, who were starving under a British blockade (5). Seven great auks were reportedly killed in 1814 at Látrabjarg on the northwest coast of Iceland. Additional reports of great auks from the 1800s and 1810s are found in various places along the Icelandic coast (5). One report from 1821 in North Iceland and another from 1828 in the south are the last known sightings on the Icelandic mainland. Several islands off the Icelandic coast bear the name 'Geirfugleasker' (meaning "Great Auk Skerry") and serve as a testament to the abundance of great auks that once inhabited the area (5). Other islands off the coast of Iceland also reportedly had great auks until the 18th and 19th centuries, including the island of Papey and the island of Grimsey (5). Most famously, the last great auks survived on the island of Geirfugleasker until it was destroyed in a volcanic eruption in 1830, after which the breeding population moved to Eldey, a sub-optimal volcanic stack where they would hold out for another 14 years (5) (See figure 5). While typical factors such as hunting and egg collection certainly played a role in the decline of the great auk in Iceland, an additional pressure pushed them beyond the brink of extinction. By the 1830s, many ornithologists had realized that the extinction of the great auk was imminent and set off in search of specimens. In 1830, Eldey became the sole known breeding site in the world, and it is reported that during this period, over 60 great auks were killed for museums and personal collections, along with an unknown number of eggs (5). This does not account for individuals gathered by locals and sold to tourists visiting the island. In 1844, the final two breeding great auks were captured, marking the last confirmed account of a great auk anywhere in the world (5). Unconfirmed reports trickle in after this date, including an alleged sale of two specimens to a reverend who refused on account of the steep price (5). The reverend doubtless did not realize what he was turning down.
The cause of the great auk's extinction seems quite clear-cut: human exploitation. Historical accounts from the 18th and 19th centuries reveal that driven by the demand for meat, feathers, eggs, and museum specimens, hunting reached even the final refuges of the great auk. While an exact date of extinction is impossible to pin down, the bird survived until at least 1844 on the island of Eldey, and probably persisted into the 1850s.
Figure 5. Eldey Island. Owing to its remoteness and inaccessibility, it was the final breeding ground of the Great Auk. Even so, many naturalists made the journey to collect specimens.
Terms of use: This image is licensed under an Attribution 2.0 Generic. It is attributed to Dagur Brynjólfsson. The image is unedited and can be found here.
Conclusion
Through our exploration of the great auk's geographic and temporal decline, it becomes evident that its extinction was not a sudden event spanning mere decades or centuries, but rather a prolonged process spanning millennia. The great auk's vulnerability to hunting pressure, coupled with its limited ability to adapt to human presence, led to its gradual retreat to the most remote corners of the world. However, even these isolated refuges proved insufficient in shielding the species from relentless human exploitation. Somewhere in the North Atlantic, in the 1840s, 1850s, or even the 1860s, the last great auk succumbed, marking the end of a truly remarkable animal.
The ecological characteristics of the great auk made it particularly susceptible to extinction at the hands of humans. As a flightless bird, it lacked the means to escape or evade hunting activities. With a docile nature and a preference for breeding on low-lying islands easily accessible to people, the great auk's vulnerability was further exacerbated. Furthermore, its reported low reproductive rate of laying just a single egg per year heightened the species' susceptibility to population decline (5, 6).
Tragically, the extinction of the great auk was still likely avoidable. Legislation aimed at protecting seabirds in Britain and Canada was enacted shortly after the last capture of a great auk on Eldey. One cannot help but wonder if a better understanding of the species' decline might have prompted a timelier response. In Newfoundland, a law was indeed implemented in the late 1700s to protect great auks. Had this law been consistently enforced, we might now be discussing one of the first success stories in conservation. Alas, the opportunity was missed, and the great auk's fate was sealed. We shall never see its like again.
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