This section on the Eurasian Black Vulture (EBV) and its captive breeding program (EEP) was prepared in April 2014 by Marleen Huyghe, bird curator Plackendael Animal Park and Antwerp Zoo (EEP studbook keeper and coordinator, Marleen.Huyghe(at)kmda.org) and Dipl. Biol. (PhD cand.) Katja Wolfram (EEP scientific advisor, K.Wolfram(at)4vultures.org).
Contact us if you have questions about the species and its husbandry.
The EEP for the Eurasian Black Vulture is coordinated by the studbook keeper and coordinator Marleen Huyghe at Planckendael Animal Park, Mechelen/Belgium, a division of the Royal Zoological Society of Antwerp. Besides holding and updating the actual register as a studbook keeper, as a coordinator she acts as a matchmaker and makes recommendations for new pairs, transfer of individuals between zoos, husbandry, captive breeding and reintroduction candidates. To make matchmaking decisions easier, the love life and genetics of the EBV as well as the captive population’s structure have been a focus of scientific research by Katja Wolfram since 2009 at the Centre for Research and Conservation, Antwerp Zoo’s scientific department.
In recent years much work has been done to tackle the breeding difficulties in the EEP. Analyses of data from more than 500 eggs laid in more than 30 years of captive breeding have led to new standards for pair formation and prompted re-pairing of a row of long-term unsuccessful breeding pairs since 2011. Especially pairs with too much age difference between partners and pairs in which one partner had reached post-reproductive age were split. Factors such as physical and behavioural abnormalities (aggressive/imprinted birds may have difficulties with pair bond, injured feet or wings may conflict with copulation and sperm transfer), kinship (inbreeding and outbreeding should be avoided) and current location (long transports are stressful for this nervous species) of individuals were considered besides ages. At present the breeding success is still low in the EEP, but there is a positive trend. With the suspension of regular reintroduction of captive-born young after 2011 and application of new reintroduction standards, there also is less pressure on the population structure in the EEP. The following figures summarize challenges in captive breeding, the EEP response and breeding success in the Eurasian Black Vulture EEP over recent years.
A prime example for successful captive breeding in a pair that was newly composed from two unsuccessful pairs is Antwerp Zoo’s current breeding pair. The pair was formed in late 2011, had a turbulent first breeding attempt in 2012 and a great first breeding success in 2013 with their first young Orion.
Development of the pair bond, Orion’s growth as well as parent-young interactions were closely followed from hatch throughout fledge and provided insight valuable for captive breeding as well as field conservation.
A video showing scenes from the initial and advanced parental pair bond, as well as parent-young-interactions can be found here>>
Within the EEP parents may sometimes need assistance with incubating or rearing. If a pair cannot rear its young, foster-rearing is the preferred alternative. Hand-rearing, in contrast, is not recommended as it often leads to imprinting and related problems. Adoptions have been done successfully many times in the past, allowing experienced parents in breeding mood to foster chicks that cannot be reared by their biological parents for one reason or another. Up till now, 13 adoptions have been arranged among EEP institutions with three failing due to nestling loss in the initial weeks, three contributing to the captive population and six greatly succeeding and leading to reintroduction of young to the wild. One such adopted and later released captive-born young was Romane.
Adoptions by EEP-parents have also been carried out for the benefit of wild-born young, illustrating how the captive
breeding program can directly help with conservation efforts in the field and save the life of a wild Eurasian Black Vulture in need.
Romane was the fourth of six fostered EEP-chicks being eventually reintroduced at a French release site over the years. A video from Antwerp Zoo of the adoption can be found here>>
Dating aviaries can help finding that special someone for unpaired captive vultures and assist captive population management in making mate choices - an especially challenging task for the supposedly monogamous, longliving and slowly reproducing species. In Planckendael Animal Park the first dating aviary was introduced over 10 years ago. In spring 2012, the original enclosure of 300 m2 was replaced by a large new dating aviary of 870 m2. The idea behind this type of husbandry is to house several young unattached vultures of both sexes together and leave their mate choices to occur spontaneously and naturally. Instead of a human matchmaker deciding for them then, literally chemistry between two individuals determines whether they form a pair.
To understand quality and development of pair bond, a set of relevant behaviours should be recorded during breeding season per standardized observation protocols. Main focus of observations is set on greeting and mutual preening behaviours, on aggression, nest building, copulation and incubation activities (bottom pictures in above figure from left to right). Contact us for protocols and information on behavioural observations.
Individuals in the dating aviary are monitored and prospective pairs are moved to a private breeding enclosure upon indication of a new pair bond. This concept has proven successful repeatedly, for example, with young male Franc whose parents found each other there in 2006 and soon moved to Czech Ostrava Zoo as a pair. Franc hatched in 2009 in Ostrava and was released to the wild in the French Verdon Gorge the same year.
Monitoring of pair bonding behaviours should be continued in newly formed pairs during breeding seasons (February to May) using standardized protocols. Protocols and an ethogram identifying relevant behaviours have been developed from first systematic observations of successful pairs in different zoos in 2008. Since then, protocols have been modified and extended, observations have been carried out in various EEP zoos by scientific staff, keepers and students and helped to understand quality and development of pair bond in the
Eurasian Black Vulture. Please contact the EEP if you are interested in ethograms and protocols.
Obscured by inaccurate studbook data for sex and origin of some individuals, the EEP is facing a problem of unexpected extend. After all, to be a good matchmaker and form successful breeding pairs, one needs to know each bird’s gender without any doubt. Nonetheless, this is not always the case and in the past five years several long-term “pairs” in the breeding network have turned out to be in fact unrecognized same-sex pairings, in most cases two females. Without any male contribution, however, eggs from those females are bound to remain unfertilized. For the EEP breeding program incorrect data on sex are devastating as they mean much potential is lost.
False or lacking information on sex is mainly a consequence of the nearly indistinguishable morphology of male and marginally larger
female Eurasian Black Vulture and the extreme
nervousness of the species. On the one hand, their physical appearance does not allow reliable sexing, on the other hand, their extreme sensitivity
to disturbance conflicts with invasive sexing methods. False data are also due to the Eurasian Black Vulture's immense life span in captivity (~40 years),
and the comparatively recent availability of DNA based sexing. Biographic data are sometimes as old as the individuals themselves and date back to when genetic analysis was not readily
available yet. Fortunately, DNA based sexing nowadays allows reliable sex determination, can be done without much
effort from shed feathers, and is an ideal non-invasive method for a highly nervous species. At Antwerp Zoo, genetic sexing is done for Eurasian Black Vultures on a routine basis using feathers and blood. During the past five years all EEP participants
were asked to submit samples of their Eurasian Black Vultures for sexing (and further scientific research). The request included detailed illustrated sampling instructions and was free of charge.
Furthermore, current studies suggest that studbook information on the origin of EEP individuals and their ancestors sometimes are also questionable and some may not have European roots as recorded but rather an Asian background. Analyzing wild Eurasian Black Vultures from across their distribution range with molecular markers reveals a geographic pattern that allows to tell individuals from different regions. Their patterns can serve as reference to verify old studbook data on the origin of captive Eurasian Black Vultures.Reliable knowledge of origin is not only crucial for captive population management, but could be also relevant for European reintroduction campaigns. After all, one would like to know who is released from captivity back into nature for the sake of the reintroduced bird and local populations.
Besides genetically confirming EEP studbook data on sex and origin, the key focus of scientific research on the EBV at present is on genetics underlying mate choice. If the genetic makeup of good and bad EBV breeding pairs can be better understood, a tool to predict which two captive vultures likely make a promising new pair could be established. A popular gene family, the so-called major histocompatibility complex (MHC), is known to play a role in mate choice in a diverse range of species, including rodents, primates and birds: Females in some species may prefer partners with a MHC very different from their own, as some studies have shown, while females in other species may prefer males with a MHC not too different. Which pattern holds true for the EBV is unknown, but studies will provide first insight soon. Along with behavioural observations and parameters of physical condition, the concentrated scientific efforts may shed light on what shapes pair bonding and hopefully provide guidance forcaptive matchmakingin the EBV.
Reintroductions to former natural habitats of the species have been successfully carried out on a continuous basis in cooperation with the EEP on Mallorca since 1988, France since 1992 and mainland Spain since 2007. In total, 47 captive-born individuals have been released until now. They are an important contribution to repopulation efforts in formerly lost habitats. Unlike the older birds that are transferred from Iberian populations every year and those that are naturally attracted to the release sites, only captive-born young can be reintroduced by hacking. This preferred method releases individuals at a very young age when they are just fully feathered and able to autonomously regulate their body temperature and eat, but not able to fly yet. While older and fully mobile birds tend to disperse, even leave their release area permanently, captive-born reintroduced young are confined to the release site throughout a sensitive age until their fledge, which is facilitating their bond to the region.
Release of young Eurasian Black Vultures Jean and Julia in the French Verdon Gorge by the hacking method in 2008. Transfer of young at age 80 to 85 days when they are unable to fly yet (A and C). Microchipping (B) at home, bleaching of flight feathers according to a unique pattern (E and I) and tagging with coded project rings and official rings (F) at the release site. Placing Jean and Julia on a natural rock platform (D and G), both tightly monitored and catered until becoming airborne. First flight attempt of Jean and departure from platform at age 112 days (H) followed by Julia at age 117 days. Photos A-H: Planckendael Animal Park; Photo I: LPO PACA.
Jean was released in the Verdon Gorge in Southern France in autumn 2008 alongside a female young of the same age, from the same location by the name of Julia. Like many reintroduced captive-born Eurasian Black Vultures, Jean and Julia descend from one family (she is his paternal half-aunt) - a result of the low and skewed captive breeding success. Being released at very early age by the hacking method, hopes were high both Eurasian Black Vulture young would get attached to their release sites and encouraged to future returns, if not even a permanent presence in the well monitored regions. Ideally, they would attract further wild vultures into the region and accelerate its repopulation - a plan that until now worked out perfectly only for Jean. Both young have fledged from their release platform at the age of 112 and 117 days in autumn 2008 and spent their first summer in the wild travelling across Southern France, with observations from the Baronnies in the West, Verdon in the middle and the Mercantour mountains in the East. Jean was frequently observed in the Verdon canyon in 2010, sometimes busy with nesting material. Julia, in contrast, was only seen in summer, went under the monitoring radar for the rest of the year and was not recognized anywhere since. EBVs in Asia are known to engage in extensive migrations between breeding and overwintering grounds. Unusual strong migratory behaviour has been reported for several reintroduced EBVs before and also Julia could have inherited an increased tendency for migration from her maternal Asian ancestors. Since spring 2011 Jean has been enjoying the company of an unknown wild exogenous female with a plumage oddity, with whom he eventually bred successfully in 2013. The pair marked the first successful wild breeding of the species in the region in over 150 years. Jean’s development in the wild is a great success and example of how the Eurasian Black Vulture EEP and its captive-born young can directly contribute to repopulating lost habitats of the species in the wild.
Young EEP-born Eurasian Black Vultures Jean and Julia in the years since their release in French Verdon Gorge. Both were still distinguishable by their unique feather bleach pattern initially. (A) Julia 2009, photo: G. Berger; (B) Jean 2011, photo: M. Pastouret. (Bottom row from left) Jean and his wild partner with Eurasian Griffon Vultures (Gyps fulvus), photos: A. Lacoste, and Jean’s first young in 2013 on the nest, photo: S. Henriquet.
EEP reintroduction standards have been revised in recent years. A profound analysis of the EEP population led to the temporary suspension of EEP reintroductions after 2011. Continuous reintroduction of EEP-young over the past decades irrespective of the low captive breeding success resulted in an unhealthy skewness in age and sexes and signatures of a reversed demography in the EEP population. On the other hand, monitoring is successful on the long-term only for less than 20% of young released from the EEP, a consequence of the loss of plumage and ring marks as well as migratory behaviour. As in the past, the EEP still aims to support reintroduction campaigns, but first and foremost has to ensure a healthy demography of its captive population. As a general rule, the first three offspring of any captive breeding pair in the EEP population will now be retained and only fourth or later young provided for release. Release candidates furthermore will be selected in a case-wise manner.
For mutual benefit and for the benefit of vulture conservation in the wild, the EEP has a very strong interest to work more closely with partners involved in reintroduction and monitoring in the field. The EEP itself can serve as a unique source of pre-fledged young Eurasian Black Vultures for release by hacking, which is important to establish a local population at any release site. It can also provide multiple decades of experience in Eurasian Black Vulture husbandry and captive breeding and in its participating zoos and parks has great potential to raise public awareness for vulture projects in the field. In individual cases, such as the young Laurita, it can also provide foster homes to wild-born chicks. Partners in the field, such as revalidation centres and monitoring organizations, on the other hand, can provide valuable insight in natural breeding of the species. They moreover can support the EEP by providing closer follow-ups of reintroduced EEP young and making non-releasable birds of matching age and sex from revalidation centres available as partners for unpaired EEP individuals.
Most information, text and figures in this section are modified from:
and references cited therein. A set of documents (protocols, guidelines) related to the Eurasian Black Vulture EEP is available upon request. Here is also a list of recomended literature:
Here you can find all pictures in a bigger size: