Northern bald ibis

The ibises are gregarious, long-legged wading birds with long down-curved bills. Along with the spoonbills they form one subfamily within the family Threskiornithidae. The northern bald ibis was described and illustrated by Swiss naturalist Conrad Gessner in his Historiae animalium in 1555, and given the binomial name Upupa eremita by Carl Linnaeus in his 1758 Systema Naturae. The species probably split into two distinct populations at least 400 years ago and, since then, the two populations have been diverging morphologically, ecologically, and genetically; Fossils of the northern bald ibis have been found at a Holocene (c. 10,000 years ago) site in southern France, in middle Pleistocene (c. 900,000 years ago) strata in Sicily, and in Pliocene-Pleistocene boundary (c. 1.8 million years ago) deposits on the Mediterranean coast of Spain. What appears to be an ancestral form, Geronticus balcanicus, was found in the late Pliocene of Bulgaria, further illustrating the early widespread presence of this genus in Europe, and suggesting that Geronticus eremita may have originated in southeastern Europe or the Middle East. ==Etymology==

The genus name, Geronticus, is derived from the Ancient Greek : gérōn, meaning old man and refers to the bald head of the aged. The species name eremita is Late Latin for hermit, from the : erēmía, meaning desert, and refers to the arid habitats inhabited by this species. The alternative common name Waldrapp is German for forest raven, the equivalent of the Latin Corvo sylvatico of Gesner, == Description ==

The northern bald ibis is a large, glossy black bird, long with a wingspan and an average weight of . The downy chick has uniformly pale brown plumage, and the fledged juvenile resembles the adult except that it has a dark head, light grey legs, and a pale bill. The unfeathered areas of the young bird's head and neck gradually become red as it matures. If the eastern and western populations are considered to be separable subspecies, it is unclear which should be considered to be the nominate (first-named) form, since the first description of this species was based on a now-extinct population from Switzerland which is of unknown race. The northern bald ibis is readily distinguished from its close relative, the southern bald ibis of Southern Africa, by the southern species' whitish face. The northern bald can also be confused with the similarly dark-plumaged glossy ibis, which overlaps its range, but it is larger and stockier than that species. In flight, when the bill and face colouration may not be visible, the bald ibis' less rounded wings and shorter neck give it a different profile from glossy ibis, and its relatively short legs mean that its feet do not project beyond the tail, unlike those of the glossy ibis. == Habitat and range ==

Unlike many other ibises, which nest in trees and feed in wetlands, the northern bald ibis breeds on undisturbed cliff ledges, and forages for food in irregularly cultivated, grazed dry areas such as semi-arid steppes, and fallow fields. The close proximity of adequate steppe feeding areas to breeding cliffs is an important habitat requirement. The northern bald ibis was once widespread across the Middle East, northern Africa, and southern and central Europe; fossil bones have been found at Solothurn dated to the Mesolithic and Neolithic Periods. It bred along the Danube and Rhone Rivers, and in the mountains of Spain, Italy, Germany, Austria and Switzerland (Gessner's original description was of a Swiss bird), and most probably also in the Upper Adriatic region. Religious traditions helped this species to survive in one Turkish colony long after the species had disappeared from Europe, since it was believed that the ibis migrated each year to guide Hajj pilgrims to Mecca. The ibis was protected by its religious significance, and a festival was held annually to celebrate its return north. The Turkish ibis population was centred near the small town of Birecik in the southeast of the country, and during the first half of the 20th century, the Birecik colony maintained a relatively stable population of about 500 breeding pairs, reaching an estimated total population of about 3,000 around 1930. By the 1970s, numbers had drastically declined and a captive breeding program was initiated in 1977 with one adult pair and nine chicks taken from the wild. This program largely failed to revert the decline; there were 400 birds in 1982, five pairs in 1986, and seven pairs in 1987. Only three birds returned from their wintering grounds in 1989, and just one in 1990. The returning birds died before they could reproduce, thus rendering the species extinct in the wild in Turkey as of 1992. Once the wild Turkish population became non-viable, the colony was maintained as a flock which was free-flying for most of the year but caged in autumn to prevent migration.—Birds from Birecik visited the Syrian colony at Palmyra. After the demise of the migratory Turkish colony, the northern bald ibis was known to survive in the wild only at the Moroccan sites, although occasional sightings of birds in Yemen, Eritrea, Saudi Arabia, and Israel during the 1980s and 1990s suggested that there was still a colony somewhere in the Middle East. Intensive field surveys in spring 2002, based on the knowledge of Bedouin nomads and local hunters, revealed that the species had never become completely extinct on the Syrian desert steppes. Following systematic searches, 15 old nesting sites were found, one, near Palmyra, was still hosting an active breeding colony of seven individuals. Although the ibis had been declared extinct in Syria more than 70 years earlier, the bird appears to have been relatively common in the desert areas until 20 years ago, when a combination of overexploitation of its range lands and increasing hunting pressures initiated a dramatic decline. The Moroccan breeding birds are resident, dispersing along the coast after the nesting season. It has been suggested that coastal fog provides extra moisture for this population, and enables the ibises to remain year-round. == Behaviour ==

Breeding The northern bald ibis breeds in loosely spaced colonies, nesting on cliff ledges or amongst boulders on steep slopes. Volunteer climbers have created extra ledge spaces in the Souss-Massa colonies to ensure that breeding population is not limited by the availability of nest ledges, In the past, the birds also nested in buildings. and are initially blue-white with brown spots, becoming brown during incubation. Both parents incubate and feed the chicks. The flocks may contain up to 100 birds in winter. As the flock moves across the ground, the ibis uses its long bill to feel for food items in the loose, sandy soil. Since this bird hunts mainly by probing, a soft surface seems to be vital, and it is important that any vegetation is sparse, and not more than high. == Conservation status ==

colony Although the northern bald ibis was long extinct in Europe, many colonies in Morocco and Algeria survived until the early 20th century, when they began to decline more rapidly, the last colony in Algeria disappearing in the late 1980s. In Morocco there were about 38 colonies in 1940 and 15 in 1975, but the last migratory populations in the Atlas Mountains had vanished by 1989. The down-listing of conservation status for the species was a controversial decision that did not take fully into account the recent extinction in the wild of the genetically unique and only long-range migratory population that used to breed in the Middle East and wintering in Eastern Africa. The northern bald ibis has declined for several centuries, at least partly as a consequence of unidentified natural causes. The discovery in Jordan of three dead adults from the Turkish colony seemed to confirm that the overuse of pesticides is still a cause of death on migration. These birds were tracked by satellite after leaving Birecik; they stopped off briefly at the Syrian colony, and were later found dead in the Jordanian desert. Although the cause of death was initially thought to have been from poison, probably laid by chicken farmers to kill rodents, the autopsy revealed that they had actually been electrocuted whilst standing on electricity pylons. Wild populations Morocco Monitoring of Moroccan wild population is guaranteed by BirdLife International partners, especially by RSPB, SEO/BirdLife and, recently GREPOM in cooperation with Souss-Massa National Park administration and the support of institutions like Prince Albert II of Monaco Foundation which is the Species Champion for Northern Bald Ibis. For the first time in the species' recorded history, there is now evidence of population growth in the wild, and the population in Morocco increased to 100 breeding pairs in the decade prior to 2008 Simple site and species protection has facilitated this growth. Quantitative assessments of the importance of sites for breeding, roosting, and foraging have guided actions to prevent disturbance and the loss of key areas to mass tourism development. Wardening by members of the local community has reduced human intrusion and increased the perceived value of the birds. The provision of drinking water and the removal and deterrence of predators and competitors enhances breeding prospects, and monitoring has confirmed that steppe and two-year fallows are key feeding habitats. In early 2019 the total population in the two colonies of Souss-Massa National Park and Tamri reached 708 birds after 147 breeding pairs that laid eggs have produced 170 chicks in the last breeding season. Maintaining such non-intensive land uses in the future may present major management challenges, and the recovery in the Souss-Massa region remains precarious because the population is concentrated in just a few places. However, it could provide opportunities for natural extension of the range to formerly occupied sites further north in Morocco. Two breeding failures were recorded in 2005 and 2008 following a change of project management and of ibis protection strategy, that occurred between 2004 and 2005 (from UN-FAO to Birdlife/RSPB management). The intent is to allow the birds to migrate once the population reaches a stable 100 pairs, excluding young. The birds are released in late January or early February to breed outside the cages on ledges and, mainly, in the nest boxes in the breeding station compound. The ibises are free flying and forage around the Birecik area in forest nurseries, agricultural fields, and along the Euphrates, but supplementary food is also provided. Decisions taken at the meeting included: In future captive breeding and releasing programmes, only birds of known origin should be used. All northern bald ibises in zoos, other than those in Turkey, are of the western population, and were imported from Morocco. Three bloodlines exist; the earliest relates to importations to Zoo Basel, Switzerland in the 1950s and 1960s, the next is the descendants of birds taken in the 1970s to stock Rabat Zoo, and the last captured wild birds were those taken to the Naturzoo, Rheine, in 1976 and 1978. Other major disease problems reported in zoo collections have been avian tuberculosis, gastric foreign bodies, bone disease, and heart problems. An outbreak of West Nile virus in Bronx Park, New York, involved northern bald ibises amongst many other species of birds and mammals. Europe In 1504, a decree by Archbishop Leonhard of Salzburg made the northern bald ibis one of the world's earliest officially protected species. They nested in the cliffs and on castles and ruins in the Graz/Steiermark and Salzburg regions of Austria and vanished around 1630–1645. A research station at Grünau has a breeding colony managed, like the Turkish population, as a free-flying flock which is caged at migration time. The aim here is to investigate flock interactions and hormonal status, behavioural and ecological aspects of natural foraging, and the establishment of traditions via social learning. The Scharnstein Project is an attempt to establish a migratory waldrapp colony by using ultralight planes to teach a migration route. The scheme builds on the Grünau research by developing a method to control and guide the autumn migration of a founder population, which then can pass this migration tradition to subsequent generations. In May 2002, 11 birds from the Vienna Zoo and the Grünau colony were trained to follow two microlight planes, and in 2003, a first attempt was made to lead a group of birds from Scharnstein to southern Tuscany. Due to adverse weather and technical problems, the birds had to be transported by road over a considerable part of the distance. On 13 January 2019 a bird released from the captive population in Rosegg Tierpark, Austria was caught alive in the town of Karlovo (CS Bulgaria). Regardless of the attempts to be rescued a few days later, it died. This is the first record of Geronticus eremita in Bulgaria In August 2013 the European Union agreed to provide support to reintroduction projects until 2019 under its LIFE+ Biodiversity programme. The Reason for Hope project under the leadership of the biologist Dr. Johannes Fritz has operated one breeding and observation site in Austria, in Kuchl, near Salzburg, and two similar sites in Burghausen, Bavaria, and in Überlingen on Lake Constance in Baden-Württemberg. The positions and flight patterns of migratory birds are monitored with light-weight solar transmitters. After learning to follow their human foster-mothers seated in ultralight aircraft, around 30 young birds are led over the Alps to spend the winter months in Tuscany. Numerous studies on migratory bird behaviour have been published and presentations given at symposiums. In November 2019 it was announced that the project team succeeded in uniting juvenile birds with experienced adult birds so that they could fly to their wintering site together. Proyecto Eremita is a Spanish reintroduction involving the release of nearly 30 birds in the Ministry of Defence training ground in La Janda district, Barbate, Cádiz Province. It had its first success in 2008, when a pair laid two eggs. This is probably the first attempt to breed in the wild in Spain for 500 years as the last definite reference to the northern bald ibis breeding in Spain is from a 15th-century falconry book. This effort has been undertaken by the Andalusian government's Environmental Ministry, the Spanish Ministry of Defence, and the Zoobotánico de Jeréz (Jerez Zoo and Botanical Gardens), with the assistance of the Estación Biológica de Doñana (Doñana Biological Station), CSIC and volunteers from the Cádiz Natural History Society. Previously, two birds left the area in 2005 and 14 in 2006, but nothing is known of their whereabouts other than that a ringed bird from Spain was seen in the Middle Atlas, Morocco in 2005. Internet pictures of this species taken near Armação de Pêra, Algarve, Portugal in 2009 and later, may be related to those releases in Spain. In 2014 the total population of this colony was 78 wild birds split into two colonies, originally along the cliffs of the Atlantic coast and in 2012 with a second colony of 5–6 breeding pairs that started at the cliffs 10 km inland next to a country road at La Barca de Vejer (Vejer de la Frontera). In 2022 the wild population of northern bald ibis living near Cádiz has increased to about 180 birds that roam an area of about 50 km. In June 2023, a pair was reported nesting on a commercial building in Rümlang, near Zurich Airport in Switzerland, with two young, the first recorded breeding pair in Switzerland in over 400 years. The adults were reported to have been tracked from the reintroduction project at Überlingen in Germany. Northern Morocco There is a planned reintroduction of the ibis at Ain Tijja-Mezguitem in the north-east of Morocco. Since the wild populations further south remain vulnerable, and the porous sandstone of their breeding ledges is exposed to erosion, the intention is to establish a non-migratory population (stocked from German, Swiss, and Austrian zoos) in an area where this species was known to have bred up to about 1980. The station in the Rif mountains was built in 2000, and stocked with the first group of zoo-bred birds. A second importation of zoo-bred birds and the construction of an information centre took place in 2004. Six pairs bred in 2006 subsequent to a change in the birds' diet, and six offspring from five nests were successfully reared. In 2007 there were 19 birds (13 adults and six juveniles) in the aviary. The rock walls of the mountains have many potential breeding ledges, and an artificial lake provides water to the birds and to the local human population. Steppe pasture which is not exposed to herbicides or pesticides gives good foraging. Once the population reaches around 40 birds, a release will be initiated, subject to international agreement. The reintroduction site is from Agadir on the other side of the Atlas Mountains, so accidental contamination of the wild colonies is unlikely. == In culture ==

. fights the Stymphalian birds According to local legend in the Birecik area, the northern bald ibis was one of the first birds that Noah released from the Ark as a symbol of fertility, It has also been used to signify the soul or spirit, one of five elements constituting personality. Herodotus wrote of the man-eating Stymphalian birds, which had wings of brass and sharp metallic feathers they could fire at their victims. Ridding Lake Stymphalia in Arcadia of these creatures was one of the twelve labours of Heracles. These mythical birds are sometimes considered to be based on the northern bald ibis, Some depictions, such as the 6th-century BC Athenian black-figure amphora in the British Museum, clearly show the black head and white body of the sacred ibis. After the bald ibis became extinct in Central Europe, some later writers thought that Gesner's description was one of several in his book depicting mythical creatures. A small illustration of the northern bald ibis is found in the illuminated St Galler Handschrift of 1562, a drawing by Joris Hoefnagel in Missale Romanum (1582-1590) and in paintings in the collection of Rudolf II at Vienna. The portal of Lukovec Castle in Lukovica pri Brezovici (central Slovenia) also features this species. In Birecik, Turkey an ancient celebration 'Kelaynak yortusu' held in mid-February to mark the return of the birds from Africa was revived in the 1950s. which has a small captive population. == References ==