Geronticus eremita

Geographic Range

The northern bald ibis ( Geronticus eremita ) was historically located in the European Alps, Northern Africa, and the Middle East until the start of the 1900’s. As of 2004 there were only two remaining populations of the ibis in Morocco and Turkey. Ninety-nine percent of the wild population could be found in Morocco. Today the ibis has been reintroduced into places such as Syria.

This ibis migrates eastward from Morocco and Turkey through countries such as Jordan and Saudi Arabia. It breeds exclusively in a small area in Syria, near the city of Tiyas.

• Biogeographic Regions
• palearctic palearctic
  • native native
• ethiopian ethiopian
  • native native

Habitat

Northern bald ibises are found in semi-arid desert, steppe regions. They feed on rocky areas or cliffs that are located near a stream or river. The rocky areas or cliffs are generally around 1400 m in elevation

• Habitat Regions
• temperate temperate
• terrestrial terrestrial

• Terrestrial Biomes
• desert or dune desert or dune

Physical Description

The northern bald ibis has a black feathered body and a face without any feathers. The face and the beak of the ibis are dull red in color. The beak of the ibis usually ranges from 130 to 135 mm. The beak size varies between male and female ibis. The northern bald ibis also has a portion of feathering around the neck known as a wispy ruff which is just a clump of feathers that looked puffed up all the time. The glossy black feathers that cover the body of the ibis help mask them while they sleep at night so that predators will not get them. The wispy ruff on the back of the neck helps protect them from being seen by covering up the head while it sleeps due to the red coloring of their head. The bills of the ibis have a slight curvature in it and this is used as an advantage to find food such as insects in the ground or in trees. The male ibis which is 75-80 cm long is most often larger in size than the female which is 70-73cm. The egg once laid for the ibis is a pale blue color and gradually turns into a brown color. When born the northern bald ibis is covered in feathers but gradually loses them over time.

• Other Physical Features
• endothermic endothermic
• homoiothermic
• bilateral symmetry bilateral symmetry

• Sexual Dimorphism
• male larger

Reproduction

Northern bald ibises are monogamous birds that only have one mate during their lifetime. The ibis find their mate by using what is known as their croop call. The male builds the nest which is a determining factor in whether the female chooses the male. The ideal nest is made of dried leaves, twigs from surrounding trees, and sometimes the male will use mud as to hold the nest together. The female picks the nest which will best suit her for when she lays her eggs. The ibis defend their nests against any of the intruders that may try to attack the nest for the eggs which may also include other ibis. This due to the fighting around the nest may cause loss of eggs due to shaking of the nest or hitting it and the egg falling out. Older birds may find their mate in a younger ibis and may be able to produce eggs but the eggs may be infertile

• Mating System
• monogamous monogamous

The northern bald ibis breeding season begins sometime in February. After the breeding pairs are found the ibis then lay the eggs between March and April. The female may lay up to 4 eggs per clutch or as few as 2. After laying the eggs the incubation period is between 24 and 25 days. The fledging period begins after the chick has hatched. Fledging generally takes about 40 to 50 days to occur. The northern bald ibis has about 2 to 4 months before it comes truly independent. Both male and female ibises reach sexual maturity between 3 and 5 years.

• Key Reproductive Features
• iteroparous iteroparous
• seasonal breeding seasonal breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual sexual
• oviparous oviparous

After laying the eggs both mates care for the eggs during the incubation period and after hatching. The male and female continue to provide care for the chicks until they reach the age of maturation, which is between two and four years. While the female is caring for the chicks the male will fly out to scavenge for food to bring back for the chicks. After returning with food the male will then take over for protection while the female leaves to scavenge for food.

• Parental Investment
• male parental care male parental care
• female parental care female parental care
• pre-hatching/birth
  • provisioning
    • male
    • female
  • protecting
    • male
    • female
• pre-weaning/fledging
  • provisioning
    • male
    • female
  • protecting
    • male
    • female
• pre-independence

Lifespan/Longevity

The lifespan for the northern bald ibis is 10 to 15 years in the wild but when kept in captivity The ibis according to Brouwer et.al.(1994) can live up to 40 years old. The oldest recorded male however was 37 years old. The oldest recorded female lived to be 32 years of age. The average longevity for a captive male or female is 20 to 25 years

Behavior

The northern bald ibis is a colonial bird that migrates seasonally. They live in groups that also flock together to the migrating habitat. They are a colonial bird which means the ibis don’t just live in pairs but also live with other ibis. The area that they migrate to is a great distance away from the place the ibis live during the nonbreeding season. The ibis does not migrate due to weather they stay in the same place until the breeding season begins. The ibis communicates using different forms of the croop. The croop is a call used by the ibis that researchers have called because it sounds like a rough cough in the throat. The male and female court each other for life. Within the social aspect of the community the northern bald ibis use a generational hierarchy, which means that the older birds tend to lead the flock rather than the younger birds.

• Key Behaviors
• flies
• diurnal diurnal
• motile motile
• migratory migratory
• colonial colonial

Home Range

The average home range for the northern bald ibis is 3.32 kilometers. The core area they will defend is 1.02 kilometers. The northern bald ibis stays close to the home range and does not usually venture out to far from it but will occasionally visit new places outside of the home. The ibis will almost always go back to the same feeding sight that is located relatively close to the home

Communication and Perception

The northern bald ibis has different call types for mating and warning. One of the calls used is referred to as the "croop." This call is used when greeting or attracting a mate. The adult and juvenile ibis have different communications due to the juvenile ibis not able to reach the frequency of the call that the adult uses. Also the communication can be distinguished between male and female due to the male have a deeper call than the female. When at the nest they use a visual perception to help identify a threat that may be coming after the eggs.

• Communication Channels
• acoustic acoustic

• Perception Channels
• visual visual
• tactile tactile
• acoustic acoustic
• chemical chemical

Food Habits

The northern bald ibis diet consists of insects, spiders, worms, small birds, fish, small mammals, and reptiles such as lizards and desert snakes. The northern bald ibis may also consume carrion.

• Primary Diet
• carnivore carnivore
  • eats terrestrial vertebrates
  • piscivore piscivore
  • insectivore insectivore
• herbivore herbivore
  • frugivore frugivore
• omnivore omnivore

• Animal Foods
• birds
• mammals
• amphibians
• reptiles
• fish
• insects
• terrestrial worms

• Plant Foods
• fruit

Predation

The population in Syria has been reduced due to the chick loss from the brown necked raven ( Corvus ruficollis ) and the Egyptian vulture ( Neophron percnopterus ). Breeding failure has been attributed to loss of eggs due to attacks from predators and also chick survival is attributed to starvation and predation.

Ecosystem Roles

The parasites that affect the northern bald ibis the most are forms of lice such as Ardeicola exilis and Colpocephalum eremitae . The northern bald ibis is a scavenger species and the list of animals it may feed on includes mice, snakes, and other birds. It mostly feeds on living insects which includes the most common food that they eat which is the darkling beetle Tribolium castaneum .

Economic Importance for Humans: Positive

The northern bald ibis is an endangered species which may lead people to want to see it if it ever were to become extinct. The birdwatching brings in tourists which causes an area to thrive

• Positive Impacts
• ecotourism ecotourism

Economic Importance for Humans: Negative

There are no known adverse effects of Geronticus eremita on humans

Conservation Status

Northern bald ibises have been a “Critically Endangered” species since 1990 according to the IUCN Red List and have continued to decline in the wild. According to CITES, the northern bald ibis is ion Appendix I which means that it is one of the most endangered species on the CITES list. Appendix I species are only to be transported in extremely rare cases. According to the U.S. federal list the northern bald ibis is an endangered species.

There have been several areas around the world that have been declared sanctuaries for this species. One of the available sanctuaries is located in Birecik, Turkey which is located near the Euphrates river so that they can be near some of the features of a wild ibis habitat. The ibis is being reintroduced into parts of their historic range (e.g.,Spain). The northern bald ibis has been a protected species since it was discovered due to it having religious traditions associated with it

Additional Links

Encyclopedia of Life

Contributors

Zachary Murphy (author), Radford University, Cari Mcgregor (editor), Radford University, Zeb Pike (editor), Radford University, Karen Powers (editor), Radford University, April Tingle (editor), Radford University, Jacob Vaught (editor), Radford University.

References

Bird Life International, 2015. "Geronticus Eremita" (On-line). http://dx.doi.org/10.2305/IUCN.UK.2015-4.RLTS.T22697488A67175023.en .. Accessed January 28, 2016 at http://www.iucnredlist.org/details/22697488/0 .

Bowden, C., A. Aghnaj, K. Smith, M. Ribi. 2013. The status and recent breeding performance of the critically endangered Northern Bald Ibis Geronticus eremita population on the Atlantic coast of Morocco. Ibis , 145/03: 419-431.

Bowden, C., K. Smith, M. Bekkay, W. Oubrou, A. Aghnaj, M. Jimenez-Arnesto. 2008. Contribution of research to conservation action for the northern bald ibis Geronticus eremita in Morocco. Bird Conservation International , 18: S74-S90.

Brouwer, K., H. Schifter, M. Jones. 1994. Longevity and breeding records of ibises and spoonbills in captivity. Interrnational zoo yearbook , 33: 94-102.

Clark, J., A. Haseley, G. Van Genderen, M. Hofling, N. Clum. 2012. Increasing breeding behaviors in a captive colony of northern bald ibis through conspecific acoustic enrichment. Zoo Biology , 31/1: 71-81.

Dorn, S., C. Wascher, E. Mostl, K. Kotrschal. 2014. Ambient temperature and air pressure modulate hormones and behaviour in Greylag geese (Anser anser) and Northern bald ibis (Geronticus eremita). Behaviorial Processes , 108: 27-35.

Krejci, J. 2015. "Monitoring of a free-flying colony of Northern Bald Ibis (Geronticus eremita)" (On-line pdf). Accessed April 11, 2016 at https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&ved=0ahUKEwiJtP7ehavLAhVFKh4KHXdIBSIQFgghMAA&url=https%3A%2F%2Fzidapps.boku.ac.at%2Fabstracts%2Fdownload.php%3Fdataset_id%3D11867%26property_id%3D107&usg=AFQjCNGGHmlLbegE85NlegIZYRA8Lc2-eA&bvm=bv.116274245,d.dmo .

Lindsell, J., G. Serra, L. Peske, M. Abdullah, G. al Qaim, A. Kanani, M. Wondafrash. 2009. Satellite tracking reveals the migration route and wintering area of the middle east population of critically endangered northern bald ibis Geronticus eremita. Oryx , 43.3: 329-335.

Lindsell, J., A. Shebab, G. Anderson. 2011. Patchiness in prey levels increases vulnerability of critically endangered northern bald ibises Geronticus eremita on their Syrian breeding grounds. Bird Conservation International , 21: 274-283.

Mallet, M. 2007. Breeding the Waldrapp ibis Geronticus eremita. International Zoo Yearbook , 17/01: 143-145.

Martin, G., S. Portugal. 2011. Differences in foraging ecology determine variation in visual fields in ibises and spoonbills (Threskiornithidae). The International Journal of Avian Science , 153: 662-671.

Serra, G., C. Bruschini, L. Peske, A. Kubsa, M. Wondafrash. 2013. An assessment of ecological conditions and threats at the Ethiopian wintering site of the last known eastern colony of critically endangered northern bald ibis Geronticus eremita. Bird Conservation International , 23/4: 399-413.

Serra, G., J. Lindsell, L. Peske, J. Fritz, C. Bowden, C. Bruschini, G. Welch, J. Tavares, M. Wondafrash. 2015. Accounting for the low survival of the critically endangered northern bald ibis Geronticus eremita on a major migratory flyway. Oryx , 49/2: 312-320.

Serra, G., A. Mahmud, A. Assaed, G. Al Qaim, T. Fayad, D. Williamson. 2004. Discovery of a relict breeding colony of northern bald ibis Geronticus eremita in Syria. Oryx , 38/01: 106-108.

Serra, G., L. Peske, M. Abdallah, A. Kanani. 2009. Breeding ecology and behaviour of the last wild oriental northern bald ibises (Geronticus eremita) in Syria. Journal of Ornithology , 150: 769-782.

Szipl, G., M. Boeckl, S. Werner, K. Kotrschal. 2014. Mate recognition and expression of affective state in croop calls of northern bald ibis (Geronticus eremita). PLos One , 9/02: 1-9.

Tintner, A., K. Kortrschal. 2002. Early social influence on nestling development in Waldrapp ibis (Geronticus eremita). Zoo Biology , 21: 467-480.

Touti, J., F. Oumellouk, C. Bowden, J. Kirkwood, K. Smith. 1999. Mortality incident in northern bald ibis Geronticus eremita in Morocco in May 1996. Oryx , 33/02: 160-167.