Saudi Arabia released 313 desert gazelles; 20 years later, both species had established themselves in a vast protected desert | World news
In one of Saudi Arabia’s largest protected desert landscapes, a conservation experiment that began in the 1990s is still visible two decades later. A total of 313 captive-bred Arabian and sand gazelles were released in Uruq Bani Ma’arid, where their movements were followed for the first time by radio tracking. When the researchers returned in 2015-2016, a large camera trap study showed that both species had established populations, although they used different parts of the reserve. Sand gazelles also changed their range with the seasons, while Arabian gazelles changed their activity as temperatures increased, spending more time active at night and around dawn and dusk.
The reintroduction of gazelles in Saudi Arabia began with 313 animals bred in captivity
Gazelles belonged to two species with a long association with the Arabian Peninsula. The Arabian gazelle, Gazella arabica, and the sandy Arabian gazelle, Gazella marica, are globally threatened. In the mid-to-late 1990s, groups of sand gazelles and captive-bred Arabian gazelles were released at several locations within Uruq Bani Ma’arid. The approach was spread across multiple sites and carried out over a period of approximately two to three years, rather than relying on a single release point.That detail mattered because the goal was not simply to put animals in the desert. The broader conservation strategy was to establish populations in suitable habitats where animals could remain protected and reproduce. The first movements of the released gazelles were followed by VHF radio tracking. It gave researchers a way to see where individual animals went after their release and how they began to occupy the protected area.
Camera traps revealed where reintroduced gazelles settled 20 years later
According to the study published in the Journal of Arid Environments, titled ‘The conservation status of the endangered gazelles of Ar Rub’ al-Khālī, Saudi Arabia‘revealed in 2015 and 2016, about 20 years had passed since the original reintroductions. Conventional wildlife studies can be difficult in a landscape as large and remote as Uruq Bani Ma’arid, particularly when animals are dispersed across different habitats.This time a large network of camera traps was used. The cameras provided a much broader picture than following a limited number of animals with radio collars. They could record wildlife in different parts of the protected area and over long periods, allowing researchers to examine both distribution and relative abundance.What emerged was not a population concentrated around the original release sites. Arabian gazelles had settled in the western part of Uruq Bani Ma’arid. Sand gazelles occupied a larger central area and their distribution changed with the seasons.
Reintroduced sand gazelles still followed seasonal habitat patterns
Sand gazelles showed particularly clear seasonal movement. During the coldest part of the year, they moved deeper into the protected area. When temperatures rose, they moved back toward the western margin. The pattern fits with the animals’ established relationship with their desert habitat. Instead of staying in a fixed section of the reserve year-round, they adjusted their movements as environmental conditions changed.Long-term observations also indicated that the reintroduced animals had retained the habitat preferences associated with their species. Captive breeding and subsequent release had apparently not erased those behavioral patterns. For conservation programs, this provides useful information. A population does not necessarily need to occupy every part of a protected landscape to be considered established. Its use of the landscape may instead reflect the ecological conditions for which it has evolved.
Arabian gazelles changed their activity patterns in the desert heat
Gazelles also responded to the desert in another way: when they were active. During the hot season, Arabian gazelles shift to activity at night and around dawn and dusk. Sand gazelles showed a similar, although less pronounced, seasonal change.In the colder season, activity was more concentrated during the day and the periods around sunrise and sunset.That change offers another view of how animals use an extreme environment. When daytime temperatures become difficult, activity may shift to colder parts of the 24-hour cycle. Once conditions are moderate, animals can spend more time active during the day.
Both gazelle species survived and established populations after 20 years.
The importance of the subsequent camera trap study was its time scale. Wildlife reintroductions can look promising soon after the animals are released, when the focus is often on survival and early signs of reproduction. A population that remains present decades later provides a different type of evidence.At Uruq Bani Ma’arid, both reintroduced species had established populations approximately two decades after the original releases. Their distributions were different, but neither had simply disappeared from the protected landscape. The Arabian gazelle had settled mainly in the western part, while the sand gazelle had spread over much of the central area and changed its range seasonally.Therefore, the findings went beyond confirming that the released animals had survived. They showed that the two species had continued to use the desert in ways broadly consistent with their known ecological preferences.
A protected landscape made reintroduction possible
Uruq Bani Ma’arid occupies part of the western Rub’ al-Khali, one of the great desert landscapes of the Arabian Peninsula. Its enormous scale creates very different conditions to those found in a small wildlife enclosure or an intensively managed reserve. The 12,684 square kilometer protected area offers enough space for animals to disperse into different habitats and alter their movements seasonally.That scale also explains why the work with camera traps was useful. Following individual animals across such a large and difficult landscape would have obvious practical limits. Instead, a wide range of cameras could collect observations from many places and create an image over time.
Reintroduced gazelles maintained different habitat preferences
Although both species were released as part of the same broader restoration effort, their subsequent distributions were not identical. Arabian gazelles were most strongly associated with the western side of the protected area. Sand gazelles were most widely distributed in the center, although they also made a pronounced seasonal movement inland during colder conditions and back toward the western edge during warmer periods.Those differences are important because successful restoration doesn’t necessarily mean that two species behave the same way. Each species brought its own ecological preferences to the restored landscape. The fact that those patterns remained visible years after captive breeding and release suggests that the animals were able to resume aspects of using their natural habitat.
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