On 18 January 2020, 15 addax (four males and 11 females), raised in managed care in the United Arab Emirates (UAE), were released to the wild in the Ouadi Rimé-Ouadi Achim Wildlife Reserve in Chad. These animals had been selected, prepared, and transported to Chad by the UAE Environment Agency – Abu Dhabi (EAD) on 13 November 2019. Upon arrival, they spent two months in a large acclimation pen in the reserve to allow the addax to adjust to local forage and climate conditions as well as for observation. When it was determined that conditions were suitable, the addax were transported to a new temporary release pen located in an appropriate habitat 30 kilometers from the acclimation pens and then released to the wild.
“We are so excited to see this coming to fruition after years of planning,” said Bill Houston, director of the Saint Louis Zoo WildCare Institute Saharan Wildlife Recovery Center. “To connect the Saint Louis Zoo’s conservation work with addax in such a meaningful way to help conserve this species in the wild is a dream come true for all of us.”
The addax, the most desert-adapted antelope in the world, may also be the rarest. Critically endangered, this iconic Saharan species numbers less than 100 in the wild by most estimates, scattered in small, isolated populations, primarily in Niger and Chad. The Saint Louis Zoo in Saint Louis, Mo., through its WildCare Institute Saharan Wildlife Recovery Center, has joined others within the international conservation community to answer an urgent call to action to address the extinction underway for addax and other Saharan species.
The Saint Louis Zoo WildCare Institute Saharan Wildlife Recovery Center is helping to underwrite the cost of the post-release monitoring of these animals through the generosity of an anonymous donor. All 15 addax were fitted with satellite tracking collars prior to their release. These collars take a position fix every two hours then relay these recent locations via satellite to the reintroduction team every 12 hours. The collars also broadcast a high frequency (VHF) signal for 12 hours each day. A Chadian tracking team on the ground in the reserve, led by Krazidi Abeye, ecological monitoring manager, Sahara Conservation Fund, use the satellite-relayed position data from the previous 12 hours each morning to direct themselves to the general area where they will search for the VHF signal from the collars.
The tracking team then uses the VHF signal to home in on the animals’ exact locations so they can observe how each addax is faring as the animals adapt to living in the wild. The satellite collar data also is relayed to the Smithsonian’s National Zoo and Conservation Biology Institute, whose research scientists developed the monitoring protocols and now direct the data analysis and interpretation.
“The collar data provides insights into such behaviors as movement patterns, seasonal preference for certain types of habitat, seasonal activity in response to temperature and weather patterns, social affiliations between individuals, and movement patterns that might signal a female is preparing to calve,” said Houston. “Knowing how they are moving, utilizing habitat, and adapting to the wild informs how subsequent releases can be fine-tuned to support the re-wilding of addax.”