Bearded Vulture Flying

The Bearded Vulture Recovery Project

Facilitator of the Bearded Vulture Task Force and Biodiversity Management Plan: Dr. Sonja Krüger, sonja.krueger@kznwildlife.com

Captive Breeding Manager: Ms. Shannon Hoffman, art@africanraptor.co.za, http://africanraptor.co.za/

Background

The Bearded Vulture Gypaetus barbatus is a Critically Endangered species in Southern Africa whose entire range in the Southern Hemisphere falls within the Maloti-Drakensberg mountains of South Africa and Lesotho. The Maloti-Drakensberg Vulture Project was initiated in 2000 to determine the breeding status of the species and has more recently undertaken research and monitoring to quantify the decline in the species, investigate the mechanisms of this decline and determine the most appropriate management actions necessary to attain the short-term species’ conservation target of a positive population growth rate.

The population is estimated at between 368-408 individuals (109-221 breeding pairs) and occupies a breeding range of 28 125 km2. Research has shown that human impacts are driving the decline, with the primary causes of mortality being poisoning and collisions with power lines. The overall foraging range of the population is estimated to be 51 767 km2 and non-adults were found to use 65% of this area whereas adults focused their activities in an area of about 286 km2 around their nests.

A Population Habitat and Viability Analysis was undertaken in 2006 to model the persistence of the population based on the available information at the time. This analysis determined that the population was declining and a Conservation Management Plan was developed for the species aimed at addressing the threats within southern Africa to ensure a positive population growth rate. A Bearded Vulture Task Force was created to ensure the implementation of the plan. The task force was created under the Birds of Prey Programme of the Endangered Wildlife Trust and includes members of the conservation authorities in Lesotho and the three relevant provinces of South Africa, the scientific community, relevant NGOs and volunteers who undertake monitoring. The conservation plan was revised in 2011 to align with national legislation in South Africa and a Biodiversity Management Plan was gazetted for the species in May 2014. The South African Minister of Environment Affairs appointed Ezemvelo KwaZulu-Natal Wildlife as the authority to oversee the implementation of the plan.

Population Viability Analysis models were redone in 2014, based on the results of more than 10 years of research on the species, to determine the future population trend and identify the primary demographic and environmental constraints on the population. The models predict a negative growth rate for the population over the next 50 years with a high probability (89%) of extinction as a result of low survival estimates and reduced productivity (55%). To achieve a positive growth rate, mortality rates should be reduced by >50%, productivity increased by >25% and the population should be supplemented by at least six individuals annually for the next 20 years.

Recovery Programme

A recovery programme is required to maintain a genetically viable in-situ population of Bearded Vulture in southern Africa. In order to reduce mortality rates, increase productivity and supplement the population, a number of objectives need to be attained:

1. The actions identified in the Biodiversity Management Plan need to be implemented to address the threats to the in-situ population.

2. A conservation breeding programme must be established to:

i) ensure a diverse and sustainable ex-situ rescue or insurance population to prevent extinction, and

ii) to produce viable chicks for reintroduction into suitable areas of their former range.

In 2015, The Bearded Vulture Task Force took the decision to implement a Conservation Breeding Programme, based on the size of the in-situ population and the trend in number as well as the IUCN recommendations to consider such a strategy when populations number less than 1000 wild individuals. This programme was initiated by Shannon Hoffman at the African Bird of Prey Sanctuary near Pietermaritzburg. This centre was chosen because of the existing permits and facilities, the available skills of the manager and the fact that it houses the only captive Bearded Vulture in southern Africa.

Methods

The recovery programme is a long term project, spanning a minimum of twenty years. The initial step is to establish a founder population of 20-30 unrelated individuals. Since there is only one individual of the sub-Saharan African sub-species in captivity in southern Africa, individuals need to be harvested from the wild.

Bearded vultures breed during winter and although they lay two eggs, only a single chick is raised each season. Therefore the biologically redundant second eggs can be harvested and the chicks hatched and raised in captivity without threatening the wild population. This method will be used to establish a founder population which will be reared in captivity. These individuals will then be matured and paired with breeding in mind, with the progeny available for release after about a 10 year period.

2015 Captive Breeding Project update

During 2015, two eggs were harvested from protected areas in KwaZulu-Natal and hatched and reared at the African Bird of Prey Sanctuary. These birds have now fledged and form part of the founder captive population. Based on the pilot harvesting in 2015, protocols have been developed to harvest eggs from the wild and to rear birds in captivity. Captive breeding of the species with subsequent introductions has been successfully undertaken in Europe for many decades and their established protocols have been adopted and implemented locally. Close ties have been formed with the European Vulture Conservation Foundation (VCF) to ensure the success of the recovery programme.

2016 Captive Breeding Project update

Early in 2016, we received some funding from N3TC towards the Captive Breeding Project. With these funds and additional resources from Ezemvelo KZN Wildlife and the African Bird of Prey Sanctuary, we aimed to harvest four second eggs from nests in South Africa and Lesotho.

The season started off well with many weeks in the field selecting a number of active nests from which we could harvest second eggs. We had some challenges with obtaining the necessary permits, but the biggest challenge of all was the weather. The entire region received heavy snowfalls at the beginning of our two week period planned for the egg harvest. Temperatures were such that the snow did not melt and prevented vehicle, foot or helicopter access to all identified sites. One site that was accessed before the snow unfortunately had no eggs even though the female had been on the nest the week prior. A second site visited at the end of the incubation period already had only one healthy chick.

Bearded Vulture on nest
Female Bearded Vulture on nest

Sadly our season therefore ended without collecting any eggs. Although the season has been largely unsuccessful, we have learnt a lot to prepare us for next year’s endeavors and we have also identified two previously unknown nest sites. On the bright side, our two juveniles that were hatched and reared by Shannon Hoffman from eggs collected last year, are doing well in their new cage with artificial cliff face. These birds can be seen at the African Bird of Prey Sanctuary near Pietermaritzburg.

Captive Bearded Vultures
Adult and juvenile Bearded Vultures at the African Bird of Prey Sanctuary.

Requirements

In order to establish a founder population of 20-30 unrelated individuals to form breeding pairs, a minimum of 30 eggs need to be harvested from the wild to take into account uneven sex ratios and illness or impaired eggs/individuals. We propose to harvest six eggs annually for the next five years from territories where pairs are known to breed regularly and which are accessible by mountaineers and the harvesting team to ensure the least amount of disturbance to the nest and egg.

Hatching of the eggs and rearing of the chicks will take place at the African Bird of Prey Sanctuary.

Conclusion

The Bearded Vulture Task Force has been in place for 10 years, during which time much has been done towards conserving this Critically Endangered trans-frontier icon. Unfortunately the critical status of the species has necessitated the implementation of a Recovery Programme for the species, but with the continued collaboration of the dedicated task force members and their respective institutions, as well as numerous stakeholders engaged by the task force over the past 10 years, the programme’s vision of “maintaining a genetically viable in-situ population of Bearded Vulture in southern Africa” can be achieved.

Juvenile Bearded Vulture
Juvenile Bearded Vulture in flight

Maloti-Drakensberg Vulture Project

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