How human intervention and climate change shaped the fate of the Northern Bald Ibis from ancient Egypt to the presence: an interdisciplinary approach to extinction and recovery of an iconic bird species

Once widespread around the Mediterranean, the Northern Bald Ibis (Geronticus eremita) became one of the rarest birds in the world. We trace the history of this species through different epochs to the present. A particular focus is on its life and disappearance in ancient Egypt, where it attained the greatest mythological significance as a hieroglyphic sign for ‘blessed ancestor spirits’, and on modern endeavours to rewild and restore the species. The close association of the Northern Bald Ibis with human culture in ancient Egypt, as in other regions, is caused by primarily two reasons, the characteristic appearance and behaviour, as well as the need for open foraging areas. In consequence, a mutualistic relationship between humans and birds was formed in some cultures. The benefit for the Northern Bald Ibis was mainly the availability of feeding habitats, which were cleared by humans for farming or grazing and might have contributed to the spread of the species. The benefit to people was primarily cultural and mythological, whereby the bird was worshiped in ancient Egypt and in Muslim cultures, while Christian cultures in Europe rather regarded it as bad omen or nuisance, like any black bird species. Another benefit was profane in nature, the species was also hunted for food, mainly in Europe. But alike many other species, proximity to humans also carried a high risk for the Northern Bald Ibis. We discuss various kinds of human impacts that were driving causes for the extinction of the species in almost all regions. However, the historical disappearance of populations also correlates markedly with changes in climate, especially in ancient Egypt and the Middle Ages. This fact has important implications for current conservation efforts, especially since international action plans for the Northern Bald Ibis have taken little account of climate change effects so far. The Northern Bald Ibis is an outstanding example of how an interdisciplinary cultural-historical and natural-scientific approach significantly promotes the interpretation of historical evidence as well as the implementation of current rewilding and restoration efforts.


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There is a growing consensus that the rapidly increasing challenges of biodiversity conservation and 44 restoration cannot be overcome without a thorough knowledge of human society and its history (1). In 45 an interdisciplinary approach social science can promote the sustainability and effectiveness of 46 conservation measures, if certain obstacles can be overcome, like suitable platforms for interdisciplinary publications or misunderstandings due to different perspectives or definitions (2). On

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The Northern Bald Ibis Bald Ibises should not be shot, but rather cherished, controlled and guarded (24,47). Even these 203 measures could not prevent extinction, but at least the last evidence for Bald Ibis occurrence in 204 Europe comes from Graz in 1621 (21).

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In the Muslim world the Bald Ibis had a better and more significant mythological image than in the 206 Christian world and they were less pursued as edible birds. In Muslim tradition, the birds were 207 worshiped because it was a Bald Ibis who led Noah and his family to the fertile lowlands on the 208 Euphrates after landing on Mount Ararat (7). In Bireçik they also honoured these birds as leaders of 209 the hajj, because they flew southward in fall in large numbers, just like pilgrims to Mecca, and they 210 returned in spring after a period common for pilgrims (4,24). For that reason, the people of Bireçik 211 used to celebrate the return of the birds in February with a traditional Kelaynak festival (kelaynak is 212 the Turkish name for the species).

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Akh in material, textual and pictorial evidence 214 Ancient Egyptians used a pictorial representation of the Northern Bald Ibis for the hieroglyphic sign 215 'akh' (Fig 2). The sign, like its living model, is easily recognizable by the shape of its body, posture, 216 shorter legs, long curved bill and a typical crest covering the back of the head. Although there are 217 many aspects of this bird's nature that must have had impact on the mind of the Egyptians, the main 218 factor in holding the bird in particular esteem and relating it to concept of the akh was probably the 219 bird's habitat (see below).   Fig 6) or former European colony sites like Salzburg on the river Salzach ( Fig   296  7), Passau on the river Danube or Uerberlingen at Lake Constance (12). This coincidence also 297 contributed to the extinction, indirectly through disturbance and destruction of the breeding sites, but 298 also through hunting and collection of nestlings out of the nests.     planes from the breeding sites to the wintering area, where they will then be released (Fig 9) is at the very beginning, we can say that the most important factor most probably was human activity 506 in and around the bird's feeding and breeding areas.

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The time of the disappearance of the Northern Bald Ibis from Egypt was the period of (I) higher human 508 activities in the fields following the need for new irrigation projects after a climate change, (II) higher 509 building activity (the species disappeared during the so-called age of the pyramid builders), which lead 510 to a higher human activity in the bird's breeding region at the limestone cliffs that were used as 511 quarries) and (III) turbulent human activities linked to social disorder that occurred after the collapse 512 of the Egyptian state at the end of the Old Kingdom, probably originally also linked with earlier climate 513 change.

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Both in Egyptology and in Ornithology, the Northern Bald Ibis represents an iconic bird species.

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Coincidently, it is connected with the notion of death and disappearance in both scientific fields. In 517 ancient Egypt, the Northern Bald Ibis was linked with the concept of the blessed dead (mighty spirits 518 called the akhu) who once disappeared from the land of the living but only to return there after a 519 successful journey through the underworld (39). In ornithological and conservation science, the bird is 520 best known for its endangerment, which almost lead to its total extinction, and for the present-day 521 attempts to save the species and to reintroduce it back to nature (71).

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This study is an outcome of a cross-disciplinary cooperation of the two authors and their respective 523 scholarly fields. The research was undertaken simultaneously in the two scientific fields, each using