3. Extinction-Date Controversy
The dodo has long been recognised as an icon of extinction [9
], but the date of that extinction remains in contention. The argument revolves around the interpretation of birds reported as dodaarsen
(“dodos”) in the 1680s—were they dodos, or had the name definitively transferred from the by-then extinct dodo to the other then still surviving flightless species, the red hen or red rail (Aphanapteryx bonasia
)? As assertions of the validity of the 1680s dodaarsen (“dodos”) continue to be published [11
] (p. 31), this paper sets out the available data in full to clarify where the weight of evidence actually lies.
Until one of us reassessed the evidence in the 1980s [12
], the last report of the dodo had been widely taken as Benjamin Harry’s report of “Dodos, whose flesh is very hard” in 1681 [13
]. However, as early as the 1860s, Alfred Newton [15
] had noted the name transfer that led Johann Hoffmann in the 1670s to use a dodo name for the red hen [16
] and, after finding a second example of the same phenomenon, ASC [12
] thought it likely that the 1681 account also probably referred to the red hen. This then left Arnhem
shipwreck survivor Volkert Evertsz’s dodo on an offshore islet in 1662 as the last record [18
]. This interpretation was generally accepted [20
] until the discovery in the 1990s, in Isaac Lamotius’ journals, of the mention of dodaarsen caught by hunters during 1685–1688, first reported by Moree [21
] and enumerated more fully (20 birds on seven occasions) by Hengst [22
] and Parish [6
]. Sleigh [23
], who worked in the Cape Archives, claimed over 50 such “dodos” were reported, but concentrating on other matters, he did not transcribe the dates and details (letter from Dan Sleigh to JCP 23.7.2009); Janoo’s claim [24
] that Moree [21
] “found written proof of dodos being alive west of Mahébourg in 1689” is not borne out by Moree’s text—the remark was in an online article that is no longer available (see Supplementary Materials S1: note 1
); “1689” may have been an error for 1688. However, the “late-date” controversy only really erupted after the publication of an additional late claim (from Hubert Hugo in 1673) by Hume et al. [25
The heart of the problem is that the dodaarsen
in the Lamotius journals reported in 1685–1688 and Hugo’s bird in 1673 are not described. The argument in favour of their being actual dodos is that these two, both opperhoofden
(commanders) of the small Dutch settlement in Mauritius, were educated men and would have known a dodo from a red hen, and that Lamotius in particular was a keen observer of nature [11
]. Lamotius was interested in medicinal plants, timber trees, and especially marine fish, carefully painting many varieties (published in [26
]), but there is no evidence in his dispatches that he was interested in terrestrial wildlife other than as food ([14
] and references therein [28
]) (see Supplementary Materials S1: note 2
). Hugo certainly knew about real dodos, as is clear from his interrogation of a recaptured slave on the run for 11–12 years [28
], but the evidence is that he realised his earlier reference to a dodaers
was an error (see below); the spellings “dodaers
” and “dodaars
” were used interchangeably by Dutch visitors and settlers. Hengst [22
] advanced a further argument for the late dodaarsen
being dodos: the hunters only mentioned large animals, and they would not have bothered with red hens, as they were too small. Against this purely speculative view, one might note that, as already pointed out [29
], hunters were using dogs that would catch flightless but not flighted birds, so might well catch the rails that would then get enumerated, even if they were of little more than snack value to the colonists.
The post-1662 date has also been supported by using statistical methods that analyse observation sequences to predict likely extinction dates [30
]. Results are highly dependent on which dates are chosen for the calculation [6
] and whether the offshore islet birds in 1662 are treated as part of a mainland continuum [29
]. The methods are useful indicators when other indications are not available, but in the case of the dodo, statistical inferences are outweighed by other evidence [30
]. Finally, a poorly defined bird in a 17th century Dutch sketch attributed to Lamotius in 1677 was claimed by Grove [32
] to be that of a dodo, but on further study, the drawing proved to actually date from 1670 (pre-Lamotius), and the bird to almost certainly be endemic sheldgoose Alopochen mauritianus
The earlier extinction date is supported by reports by Dutch settlers that abundant feral pigs, originally introduced in 1606 [4
], sought out and ate tortoise and turtle eggs [28
] (see Supplementary Materials S1: note 3
); thus, it can be inferred that they would likewise eat ground-nesting-bird eggs [4
]. In the Galapagos, feral pigs are prime predators on giant-tortoise eggs and hatchlings [38
]. Dodo nests, as reported by Cauche [40
], and like those of the related Rodrigues Solitaire [41
], were not concealed, whereas those of the red hen, if like those of its Rodrigues sister species Erythromachus leguati
, would have been very hard to find. In two years on Rodrigues, 1691–1693, François Leguat [41
] and his companions never found a nest. Aphanapteryx
, like most rails [42
] (Appendix A
), probably had a larger clutch size than the dodo (one egg: [40
]); dodo eggs, being larger, would have taken longer to incubate and would have thus been vulnerable for a longer period than those of the smaller rails. Macfarland et al. [38
] noted that the long incubation period of tortoises increased their vulnerability to pigs. Hence, it is likely that dodos were decreasingly able to successfully once pigs had overrun the island in the 1620s [12
], whereas, still breeding well, the rails could even have benefitted in foraging from the pigs’ digging, scraping, and rooting, as does the New Zealand weka (Gallirallus australis
), a flightless rail of similar size to Aphanapteryx
4. Name Transfer
The key to the interpretation lies in the account of Johan Hoffmann and a more recently discovered earlier account by Johannes Pretorius [43
]. Both lived on the island for two to three years and left rather complete faunal lists. Pretorius (on the island 1666–1669) was effectively second-in-command (and considered for commander [43
]); almost a decade later, Hoffmann (1673–1675) was the community’s spiritual preacher or pastor on the island. Both were therefore fully embedded in the settlement’s activities, would have known all the inhabitants, and been familiar with hunting activities and what the local animals were called. Hoffmann [44
] published a book of his travels, but Pretorius’s manuscript memoir only recently surfaced. A further faunal account in 1666 by a contemporary of Pretorius, Jacob Granaet, mentions no flightless birds [14
Given their long involvement in the community, one must assume that Pretorius and Hoffmann’s faunal nomenclature matched what was in general use at the time, and indeed, for all but one species, their usage is unexceptional—pigeons, parrots, geese, ducks, bats, tortoises, and domestic livestock carried their usual names, as did the “Indian ravens”, the long-standing Dutch name for the large semiflightless parrots Lophopsittacus mauritianus
, long since extinct [4
]. The one exception is that both writers’ cases described as dodaers/toddärsche birds that are clearly, from their descriptions, the red hen:
The dodaers is a red bird, as big as a fowl, has short wings and cannot fly. It scratches in the earth with its sharp claws like a fowl to find food such as worms under the fallen leaves. This bird is unbelievably stupid. When one waves a stocking cap and makes a sharp sound with the mouth, it immediately heads towards that person, and if one carries a stick, all of them can be killed with it without any escaping. They are fatty and greasy to eat. They have a long, sharp beak which is slightly curved at the end.
[there is also] a particular sort of bird known as toddärschen, which is the size of an ordinary hen. [To catch them] you take a small stick in the right hand and wrap the left hand in a red rag, showing this to the birds, which are generally in big flocks; these stupid animals precipitate themselves almost without hesitation on the rag. I cannot truly say whether it is through hate or love of this colour. Once they are close enough, you can hit them with the stick, and then have only to pick them up. Once you have taken one and are holding it in your hand, all the others come running up as it to its aid and can be offered the same fate.
From this, it is abundantly clear that, during the second Dutch settlement from 1664, the red hen had inherited the dodo’s name, the inference being that the true dodo was by then extinct, and, expecting to find flightless birds called dodaers
, the settlers used that name for the only flightless bird they found. As Alfred Newton wrote 150 years ago:
… it would appear from this that in Hoffmann’s time in Mauritius one common name for the dodo had been transferred to another species of bird in accordance with that odd process of substitution which has obtained in so many countries, where the rightful owner expiring bequeaths (as it were) its titles to a survivor
John Marshall, an English visitor, travelling on the Unicorn, who landed in 1668 on the other side of the island and had no contact with the Dutch settlers [22
], also employed a name transfer, even using two names for the bird:
Here are also great plenty of dodos, or red hens, which are larger a little than our English henns, have long beakes and no, or very little, Tayles. Their fethers are like downe, and their wings so little that it is not able to support their bodies; but they have long leggs and will runn very fast, that a man shall not take them, they will turne so about the trees. They are good meate when roasted, tasting somthing like pig, and their skin like pig skin when roosted [sic], being hard.
British mariners presumably also expected flightless “dodos” from past visits and thus likewise applied the name to the only flightless bird they saw. The ship’s log [45
] mentions goats, hogs ducks, and geese, but not “dodos”.
There is further evidence of the dodo’s absence in remarks made by Hubert Hugo in 1674. Having claimed that a dodaers had been caught in August 1673 [11
], Hugo sent a team of men in January of the following year to search the interior for a fortnight in search for escaped African slaves reported to be hiding out somewhere. They discovered and detained an ex-slave named Simon, found in an encampment some 7–8 leagues into the interior, whom Hugo questioned about his life during the 11–12 years on the run [28
] (items 650–667). In his report, Hugo wrote, inter alia, that:
He [Simon] also told us that even though he had been so long in the country, he had only twice seen a dodo, the size of a cassowary. These are apparently the dodos ‘walgvogels’ that are mentioned from the first discovery of the island. Nevertheless, it is the case that no Netherlander, however long his stay here, can truly say that he has seen one of these birds (Hugo in [28
] (item 6660, [30
]; ASC’s translation of Leon Doyen’s French translation of Hugo’s Dutch). (see Supplementary Materials S1: note 4
It is unclear whether Hugo specifically asked about dodos, or if Simon volunteered seeing larger birds that Hugo and the colonists had seen. The reference to walgvogels,
the name used by the first Dutch visitors in 1598, makes clear that, by then, Hugo had become aware of and interested in true dodos, and that none of the settlers had ever seen one! Clearly, he must by then have realised, perhaps through belated reading, that what they (the settlers) had caught and were calling dodaersen were not actually dodos. This throws into sharp doubt the interpretation [11
] that his 1673 claim referred to dodos rather than red hens. It is harder to interpret Simon’s account as a reference to a cassowary, an Australasian bird known in Holland but unlikely to be familiar to an African slave, suggesting that Hugo may have asked leading questions. In any case, Simon would have wanted to stay on the right side of his captor, although it doesn’t appear that Hugo recognised him; he had originally escaped from Hugo’s own ship in 1662 [29
]. It is clear from the tone of the discussion with Hugo [28
] (items 650–667) that he was in fear of his life, so he may have offered answers he thought Hugo would like to hear. Hugo, on his earlier visit as a privateer, rescued a number of survivors (including Andries Stokram) of the shipwrecked Arnhem in November 1662 [21
], but not the group that had found the dodos on Ile d’Ambre off the east coast; Stokram [46
] later published an account, see below. The survivors Hugo rescued had not seen dodos. Those that had (including Evertsz), had already left in May on an English ship [21
]. Hence, Hugo may not have been particularly aware of the dodo situation when he returned as opperhoofd in 1673. In late 1673, he wrote a long report, including wildlife information, that mentioned neither dodos nor red hens [47
], and in his January 1674 diary, he mentioned species hunted by his teams—all large mammals, tortoises/turtles, and fish [28
]. While Simon may well have encountered scattered elderly dodos in the forest, or had seen them on Ile d’Ambre (if Evertsz left any survivors; see below), for the reasons given his account must be treated with caution, and there is no indication of when during 1662–1674 he had the claimed sightings.
In the context of these accounts, it is difficult to see how post-1674 references to undescribed dodaersen/dodaarsen can be construed as dodos; relying on Lamotius’ supposed and totally unproven knowledge of real dodos should not overrule the strong indications to the contrary. Given that the settlers had used dodaers/dodaars
for red hens since the mid-1660s, and that no-one had reported two sorts of flightless bird for over twenty years, the obvious inference is that Lamotius was simply using local usage and reporting the capture of red hens by his hunting parties. Moreover, the large number [23
] suggests that Lamotius’ birds were more common than those reported by Simon—in keeping with a red-hen identification, but evidently not with a dodo one. Likewise, Benjamin Harry, the crew whose ship Berkley Castle interacted with the Dutch for meat supplies [14
], would have got the dodo name from the locals:
Now having a little respitt I will make a little descripti: of ye Island first of its Producks and yn of itts parts—ffirst of winged and feathered ffowle ye less passant. are Dodos whose fflesh is very hard.
The obsolete term ‘passant’ has had several somewhat contradictory meanings, but here appears to mean ‘excellent’ (the earliest recorded meaning according to the Oxford English Dictionary); Jackson’s argument (48) that Harry would not mistake red hens for dodos is based on misunderstandings [29
Harry also mentioned “reasonably good teal, curlews, flamingoes, turtle-doves, large bats, many small birds which are good [to eat]” [14
]. The ship’s log of the President that was there at the same time [29
] reported ducks and geese, but no mention of dodos (or red hens). Published logs of English ships that called during 1688–1690 for wildlife list only turtles and ungulates caught by dogs [14
]. Faunal remains of animals eaten by members of the second Dutch settlement excavated at the site of Fort Frederick Hendrik at Grand Port do not include dodos, red hens, or indeed tortoises [49
], suggesting the surviving deposits date from late in the period of occupation when all these were very rare or extinct.
Given that there had probably been no breeding on the mainland since the late 1630s, any surviving dodos in the 1680s would have been 45–50 years old, plausible for some seabirds and parrots, but way beyond anything known in pigeons [50
] - the oldest known pigeon, a captive domestic Columba livia
, lived 35 years, the oldest wild pigeon only 22; however, there are only data for a small proportion of pigeon species. However, the dodo was much larger than ordinary pigeons, and using the mass estimates of Heteren et al. [51
] of 8–18 kg and Lindstedt and Calder’s [52
] wild nonpasseriform model yields potential lifespans of 24–28 years for the dodo. Being a flightless insular bird, the dodo may have had a comparatively longer lifespan than volant columbids [42
However, if a tiny number had somehow survived, bred in the interior, and had escaped all observation from 1664 to 1681 (or 1685), then these birds reported in the 1680s might have been dodos—but without any description to flesh out these dodaersen, and the clear evidence that the name had been used locally for red hens since the mid-1660s, it is reasonable to infer that these birds were in fact red hens.
5. Last Definite Dodos
It remains to sum up the details of the confirmed last dodo dates. As can be seen from Table A1
, dodos were reported regularly on the Mauritian mainland up to and including 1638, but, apart from the bird exported in 1647, not thereafter. After that, we have only the Evertsz report in 1662 on the pigfree offshore islet.
On the mainland, the last in situ sightings are those of François Cauche’s associates in 1638, who reported details of their appearance and nest for him to imply he had seen them himself [4
]. In that same year, Peter Mundy, admittedly on a very short visit, pointedly commented on not seeing any, while noting he had previously seen a couple in captivity in Surat, India (sometime during 1628–1634 [6
In Prince Maurice’s Island I have seen Birds bigger than Swans, without any Feathers on their Bodies, which are cover’d with a black Down, their Breech quite round, the Rump adorn’d with curl’d Feathers, as many in Number as the Bird is Years old. Instead of Wings they have Feathers like those last mention’d, black and bowing. They have no Tongues, the Beak thick, bowing a little downwards, long scaly Legs, with only three Claws on each Foot. They make a Noise like a Goose, and are not so well relish’d as the Fouches
above mentioned (see Supplementary Materials S1: note 5
). They lay but one Egg, as big as a Penny Loaf, by which they place a white Stone, as big as a Hens Egg, and that on Grass they bring together for the Purpose, and build their Nests in the Woods. If the young One be kill’d, there is a grey Stone found in its Guizard. We call them Birds of Nazareth, perhaps for having been found in the Island of Nazareth, which is above that of Prince Maurice, in 17 Degrees of South Latuitude. The Grease of these Birds is of excellent Use to supple the Nerves and Muscles.
(Cauche, from the English translation of [40
], in 1710, pp. 54–55)
The Dodo. Allthough wee now Mett with None, yett Divers tymes they are Found here, having seene 2 att Suratt broughtt From hence, and as I remember they are as bigge bodied as great Turkeyes, covered with Downe, having little hanguing wings like shortt sleeves, altogether unuseffull to Fly withall, or any way with them to helpe themselves. Neither Can they swymme butt as other land Fowle Doe [when] on Necessity Forced into the water, beeing Cloven Footed as they are.
] (vol. 3 part 2, p. 352)
After this, the only definite record likely to be from the mainland is the well-attested account of one shipped as a rarity (together with a white deer) from Batavia (now Jakarta; the Dutch eastern capital) to the Dutch trading post at Deshima in Japan in 1647 [55
]. In caves at Baie du Cap and Treize Cantons thought to have been temporarily occupied by maroons (escaped slaves), the presence of dodo bones with cut marks [57
] indicates that the species was still present on the mainland post-1642, when slaves were first imported and escaped [21
], although earlier occupation of the caves by shipwrecked mariners or visitors exploring cannot be ruled out (Amitava Chowdhury, pers. comm.). The presence of a didosaurus Leiolopisma mauritiana
frontal bone in the Baie du Cap assemblage [57
] (Chapter 7 plate 28; identification by Julian Hume, pers. comm.) means the bones were of mixed age, as this giant skink was extinct before the first Dutch arrived in 1598 [4
]. There has been no published taphonomic analysis and no carbon dating (Chowdhury, pers. comm.) of the excavated sites, and no culturally identifiable artefacts found [58
]; thus, more precise dates have so far not been determined. Chowdhury [57
] illustrated faint apparent cut marks on a dodo’s toe bone (), and mentioned cut marks on a vertebra and rib. However Julian Hume (pers. comm.) thinks these marks are not cut marks, but caused by some kind of post-deposition event; one might also ask why anyone would cut a toe bone, though extracting potentially useful tendons might be a possibility. Janoo’s [24
] (Figure 2) photograph of bones from the Baie du Cap site shows a tarsometatarsus with damage consistent with a blow from a blade, but that could be a natural cross-fracture on a deteriorated bone.
Apart from Cauche, Mundy, and the Japanese delivery, faunal accounts and indeed recorded visits during the first Dutch settlement (1638–1658) are lacking. The English ship Dolphin in 1644 reported only hogs and goats [14
], and the limited Dutch accounts only refer to introduced ungulates [8
]. Hence, there is currently a lacuna here in the dodo’s history, though unpublished documents may yet be found to fill it.
Finally, there is Volkert Evertsz’s account, following the shipwreck of the Aernhem, of wading out an offshore island where, inter alia, he and his companions found (and ate) dodos [6
]. It is clear from his account and those of two other survivors ([46
], Kerkhoven in [6
]) that none was seen on the mainland. Although accessible on foot at low tide, Evertsz’s faunal list indicates that while, there were goats on the islet, identified as Ile d’Ambre [19
], there were no pigs or monkeys—in the absence of these predators, dodos could still successfully nest, until probably wiped out by the shipwrecked Dutchmen. The goats had clipped ears, indicating that they had been placed there by the Dutch of the first settlement [18
]. By 1673, Hugo et al. [47
] reported that goatherds were once again on the islet, blamed for wasteful slaughter of tortoises and goats—no mention of dodos.
Amongst these birds were those which in India they call Dod-aersen (being a kind of very big goose); these birds are unable to fly, and instead of wings, they merely have a few small pins, yet they can run very swiftly. We drove them together into one place in such a manner that we could catch them with our hands, and when we held one of them by its leg, and that upon this it made a great noise, the others all on a sudden came running as fast as they could to its assistance, and by which they were caught and made prisoners also. Here we also got some Mountain Partridges [berghoenders, i.e., Red Hens]; and as to wild Goats, these we could get as many as we pleased. We needed only to drive them together into a corner, running from the land towards the sea-side and making a kind of projecting island, when afterwards we ran with our five men amongst them, catching in this manner as many of them as we pleased. Some of the old goats had cuts in their ears, which made us suppose that they had been left there by the Netherlanders at the time they dwelled here on this island.
The published records of dodos and red hens are in Table A1
, and the pattern of sightings is summarized in Table A2
. Unfortunately, the involved numbers are too low to allow for any statistical test.
Red hens, clearly still common in the 1670s and apparently (Lamotius’s dodaarsen) the 1680s, probably succumbed to feral cats introduced around 1680 [4
]; they were last mentioned, as having become rare, by Leguat [41
] (gelinotte) in 1693–1696.