Antelope conservation: exporting experience from Tunisia across the Sahara
Many thanks to Marie Petretto, Tania Gilbert, and Philip Riordan for this article giving a useful overview on the experience of Marwell Wildlife, SCF long-time partner, with antelope conservation in Tunisia and in the Sahara.
Once abundant and widespread Saharan antelopes, such as scimitar-horned oryx (Oryx dammah) and addax (Addax nasomaculatus) have dwindled towards extinction during the twentieth century. Tunisia recognised the dramatic loss of its natural heritage early, and was amongst the first range countries to implement a national strategy to return these emblematic ungulates to their natural habitats.
More recently, a joint project between the Environment Agency-Abu Dhabi (EAD) and the Chad government, with the Sahara Conservation Fund as the implementing agency, led to the release of captive-bred scimitar-horned oryx (SH oryx) from Abu-Dhabi, into the extensive unfenced Ouadi Rimé-Ouadi Achim (OROA) Reserve in Chad, several decades after they were extirpated by over-hunting and habitat degradation.
Since the first release of SH oryx in Tunisia’s Bou Hedma National Park in 1985, and the subsequent Djerba Declaration in 1998, Marwell Wildlife has collaborated in a long-term partnership with the Tunisian Direction Générale des Forêts (DGF) to restore antelopes and their arid ecosystems in Tunisia. Our work has focused on monitoring these animals and their role in the aridland ecosystems. Our surveys address key questions on population viability, habitat use and animal health using a range of techniques including population genetics, biodiversity assessments, and population modelling.
Photos © Chawki Najjar / Marwell Wildlife
In 2012, the EAD convened a team including the IUCN SSC Conservation Planning Specialist Group, the Smithsonian Conservation Biology Institute, RZSS and Marwell, to model scenarios of reintroduction success. The baseline model was adapted from one that Marwell developed for the reintroduction of SH oryx to Tunisia’s Dghoumes National Park in 2007.
Genetic evaluation by EAD and RZSS of the captive population for reintroduction to Chad indicated they would benefit from additional lineages, and in 2015 Marwell transferred 14 SH oryx donated by several European zoos (EAZA) to Abu-Dhabi. Together with SH oryx transferred from North America, they increased the population’s genetic diversity at the EAD. A similar approach to creating genetically diverse founders for reintroduction was employed in Tunisia in 2007, when animals from EAZA and North American zoos (AZA) were released into Dghoumes National Park.
Photos © Marie Petretto / Marwell Wildlife
There are substantial differences between the reintroduction of SH oryx to the large unfenced OROA Reserve in Chad and the smaller fenced protected areas in Tunisia. Unlike the OROA population, those in Tunisia require ongoing management to ensure long-term sustainability. Marwell works closely with the DGF and reserve managers to implement strategies that address issues of limited carrying capacity and small population size. These management strategies are informed by modelling, logistics, and genetics, thanks to generous support from SCF, RZSS, Le Cornelle (Italy), Monde Sauvage (Belgium), and Dublin Zoo (Ireland).
Our team’s success with SH oryx has stimulated similar Marwell & DGF projects for reintroduced addax (in partnership with RZSS, Al Ain Zoo-UAE and San Diego Zoo Global-USA), and the North African ostrich in Tunisia (for more details visit www.marwell.org.uk/conservation).
Photos © Chawki Najjar © Marie Petretto / Marwell Wildlife
Sadly, many countries do not have protected areas of sufficient size and with enough suitable habitat to support self-sustainable populations of large-bodied animals. Our fragmented population model may be the only pragmatic option that many countries can adopt if they want to see the return of these species. Marwell and the DGF are working to recreate natural species assemblages through management interventions across the network of protected areas in Tunisia, and the results will inform similar projects in other areas. An already tangible output is the Tunisian strategy for “re-wilding” areas that have been intensively overgrazed by domestic livestock.
Tunisia has demonstrated a strong commitment to the conservation and restoration of Sahelo-Saharan wildlife, and Marwell is honoured to partner with the DGF and will continue to collaborate on Tunisian conservation initiatives for the foreseeable future.
M. Petretto, T. Gilbert, P. Riordan - Marwell Wildlife