How to bring a species back from extinction

by ZSL on

The scimitar-horned oryx has been declared extinct in the wild since the 1990s. ZSL has been working on a ground-breaking collaborative project to bring them back as ZSL conservationist, Tim Wacher, explains. 

Scimitar-horned oryx are returned to homelands on the edge the Sahara desert
Scimitar-horned oryx

A ground-breaking project has been initiated by the Environment Agency of Abu Dhabi and the Government of Chad, and supported by global partners including the Sahara Conservation Fund and ZSL’s conservationists, to restore the iconic scimitar-horned oryx to its former range in the arid grasslands of central Chad. 

This reintroduction programme is the culmination of over 40 years of conservation work on desert antelope by ZSL, with the first captive-bred scimitar-horned oryx release taking place in August 2016, where 21 animals were released into the vast Ouadi Rimé-Ouadi Achim Game Reserve.  

This remote, 78,000 square kilometers Reserve was one of the last places scimitar-horned oryx were found in the wild and is now the best hope for their future. The scale of the operation makes it one of the largest and most ambitious species reintroduction projects attempted anywhere in the world. 

A second release was completed in January 2017, bringing the total number of oryx released so far up to 36. A further 37 animals have arrived at the site to acclimatise in specially built pens prior to release, and more are scheduled to join them from the ‘world herd’ in Abu Dhabi - a group assembled by the EAD from the world’s captive populations to provide the best possible oryx to Chad. 

First oryx leaving the enclosure
First oryx leaving the enclosure on 21 January 2017

ZSL’s main focus is to aid a local team in tracking the progress of the oryx once released into the wild. ZSL is one of an array of partners brought together by EAD to ensure the success of different aspects of the reintroduction programme.  The timeline below describes the long history of ZSL’s involvement and commitment to desert antelope conservation, leading up to our role in this exciting project.

1960s - ZSL played a role in the international effort to stop the extinction of the Arabian oryx by participating in the then relatively novel idea of collaborating with other organisations and zoos to create a significant captive breeding population. Thirty years later, ZSL staff participated in monitoring the released Arabian oryx in the vast Saudi Rub al Kali.

1970s - The success of the Arabian oryx initiative was followed up in the 1970s, when David Jones (later Director of Zoos at ZSL) teamed up with John Knowles (founding Director of Marwell Zoo) to go and visit John Newby, who worked on scimitar-horned oryx in central Chad.  This was the founding of an important partnership for ZSL that has lasted to the present day. 

The international unrest that contributed to the subsequent extinction of the wild scimitar-horned oryx (the front line between Chadian and Libyan armies lay right across their last important heartland for a protracted period) prevented any significant conservation activity in Chad at that time.  But as the situation unfolded and the plight of all the larger wildlife of the region (addax and dama gazelle, ostriches and cheetah, as well as the oryx) became apparent, attention was turned to neighbouring Niger.  ZSL participated in several expeditions into the desert with John Newby and others in the late seventies and proposals for captive breeding centres for oryx, addax and other species were developed. Unfortunately the funding for these projects could not be found. 

Scimitar-horned oryx are released
Scimitar-horned oryx are released into the vast Ouadi Rimé-Ouadi Achim Game Reserve

1980s - By this time, attention was switched to Tunisia when an unexpected request was received to supply scimitar-horned oryx to a newly created fenced National Park at Bou-Hedma - oryx are believed to have lived in southern Tunisia a long while ago.  ZSL teamed up again with Marwell and Edinburgh zoos to supply a small group of young scimitar-horned oryx to Bou-Hedma. Some preliminary monitoring of their ability to survive the transition from English fields to thorny North African steppe was initiated and the animals coped extremely well.  Similar projects also emerged in Morocco.  However, all these efforts in Tunisia and Morocco are in restricted fenced areas. 

But still no oryx had been returned to their most recent ranges on the southern side of the Sahara.

1990s Through the 1990s, ZSL was mainly occupied with, and gaining huge experience from, the effort to captive breed and restore two species of gazelle and the Arabian oryx to the wild in Saudi Arabia. To this day, the gazelle reintroductions remain amongst the most successful reintroduction programmes in the world. 

At the very end of the decade, ZSL took part in a conference at Djerba, Tunisia which brought together international antelope conservationists and government representatives from all 14 nations that had threatened Saharan antelopes.  As well as creating official support for antelope conservation in Saharan nations, an interest group for Saharan antelopes was formed under the initiative of Steve Monfort of the Smithsonian Conservation Biology Institute in Washington, working again with John Newby. 

Mother and calf from Aug 2017 release
A scimitar-horned oryx with her calf

2000s - In the early 2000s, ZSL was invited by Steve Monfort and John Newby (whom later formed the NGO, Sahara Conservation Fund in 2004) to help with extensive surveys of former oryx and addax ranges in both Niger and Chad.  Sadly it was consistently reported by the Chadian nomads of these remote regions that all the oryx had gone to Niger, and in Niger they said the opposite! Only broken pieces of oryx horn were found in former haunts.  However, remnant groups of both addax and dama gazelle were found in Chad and Niger, showing that large antelopes were surviving  in both countries.   

Meanwhile, ZSL worked closely with Renata Molcanova, founder of the population of scimitar-horned oryx (created by the Bratislava Zoo) in the 60 square kilometers Sidi-Toui National Park in eastern Tunisia.  Over several years of short study visits, these animals allowed ZSL to document fascinating behaviours with clear signs that captive-bred scimitar-horned oryx could develop a social structure akin to that expected in the wild.  

2010s - ZSL have continued to work with the newly formed Sahara Conservation Fund, founding much of the basic monitoring and survey work that contributed to the creation of the Termit and Tin Toumma National Nature Reserve in Niger in 2012. The reserve encompasses the last known significant population of addax as well as dama gazelles in the Termit Massif. 

From 2011, ZSL was again contracted by the Sahara Conservation Fund to run a series of more detailed surveys in Chad, Niger, Algeria and Tunisia known as the ‘Pan-Sahara Wildlife Survey’, which focussed on assessing the best location for a potential oryx re-introduction.  The Ouadi Rimé- Ouadi Achim Game Reserve in central Chad was found to be the most suitable.  

In 2012, ZSL participated in a major stakeholder meeting held in the national capital, N’Djamena. The meeting was strongly in favour of the prospect of returning the oryx to Chad, if funding could be found.   

ZSL has played a long term role in building a solid information base to support this re-introduction. The even longer history of John Newby’ s involvement with the country, as well as ZSL and many others, has been a key additional factor in bringing together all parties and ultimately attracting the vital interest of the Environment Agency of Abu Dhabi.  

The EAD has acted decisively to enable an impressive and collaborative effort, making possible this remarkable opportunity to reverse the status of the only large African mammal still classified by IUCN in 2016 as ‘Extinct in the Wild’. 

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