The critically endangered European ground squirrel has appeared in the Podyjí National Park for the first time in 50 years, thanks to wild horses
The grazing of wild horses has helped one of the most endangered mammals of central Europe return to the Podyji National Park. The critically endangered European ground squirrel has settled in the park’s territory for the first time in fifty years.
The natural grazing of large ungulates again showed its potential for facilitating the return of endangered species to the countryside. Ground squirrels (or sousliks) came to the heaths that are part of the Podyjí National Park from a site a few hundred metres away where they have been found for several years now. “It is no coincidence that ground squirrels have found a suitable biotope specifically on the Havraníky pasture. Short-stemmed grasses, which form their biotope, have been restored there thanks to wild horses,” said Miloslav Jirku from the Biology Centre of the Czech Academy of Sciences.
Dense tall-stemmed grasses covered the location where ground squirrels are currently found as recently as 2018, when the grazing of wild horses on the heath began. These are totally uninhabitable for the ground squirrel. However, grazing positively affected the location after a few years and created suitable conditions not only for sousliks but also for rare flowers such as pasqueflowers. In addition, continued grazing will secure an appropriate environment in the long term for ground squirrels in the future. “Grazing of wild horses can cheaply maintain suitable conditions in the long term not only for sousliks but also for other animal and plant species that require sparse grasses rich in flowering herbs,” Dalibor Dostal, director of the European Wildlife conservation organisation that set up the pasture reserve, pointed out one of the greatest assets of grazing large ungulates. Spontaneous inhabitation of the heath by ground squirrels is a notable moment in the efforts to save this species as part of domestic nature conservation.
Other good news is that sousliks not only inhabited the site but they also started reproducing there. “Summer monitoring demonstrated successful reproduction of sousliks following the discovery of souslik burrows in the spring. One litter of youth was observed. Overall we estimate that up to 10 ground squirrels live on the pasture for wild horses. Successful hibernation until spring will be key for further development of the small local colony. We will not be able to evaluate that until next spring,” stated Tereza Brzobohata from the Nature Conservation Agency of the Czech Republic, who coordinates the souslik rescue programme in the Czech Republic.
The survival of the newly forming, still fragile population of sousliks will not be easy due to extreme climatic conditions. “Sousliks do not have an easy life this year at all. Similarly to the whole region, heaths face great drought. The drought combined with extreme heat waves resulted in the vegetation of the local meadows and heaths drying up so quickly that it had no chance to respond. The covers crack under one’s feet, and there are hardly any green plants to be seen. This means that sousliks have to set out on a long journey from their burrows to find food, which exposes them to danger posed by predators. It is not certain whether the sousliks will manage to create sufficient fat reserves for the winter and survive their first year at Havraníky,” said Robert Stejskal from the Podyji National Park.
“On the other hand, long-term monitoring of souslik populations in the Czech Republic suggests that the most noticeable increases in souslik numbers at individual sites as well as a blanket expansion of populations and the formation of satellite colonies occur specifically in dry years. This was very evident in the dry period from 2017 to 2019. By contrast, humid years such as 2021 do not benefit sousliks. Of course, extremes are risky for all species, the ground squirrel included. However, ground squirrels can demonstrably cope better with drought than wet periods. That’s why we’ll have to wait until the upcoming years for a result,” points out Jan Mateju from the Karlovy Vary Museum, who carries out the monitoring of sousliks as part of the rescue programme.
Photo: Jan Mateju
