The Caprinae are a subfamily of the Bovidae family which includes goats, sheep, and their relatives. In modern times there are three genera of the Caprinae that are considered native to Europe, including a combined seven species. The first is the Capragenus, which includes the four European species of ibex: the Anatolian ibex (Capra aegagrus), the Caucasian ibex (Capra caucasica), the Alpine ibex (Capra ibex), and the Iberian/Pyrenean ibex (Capra pyrenaica). The second genus is Rupicapra, which includes the two species of chamois: the Iberian/Pyrenean chamois (Rupicapra pyrenaica) and the European chamois (Rupicapra rupicapra). The last genus is Ovis, which includes the wild sheep, or mouflon (Ovis orientalis). The geographic history of these species within Europe is complicated, and there was a fourth genus present in the area during the mid-late Pleistocene, which will also be discussed. Muskoxen and their extinct relatives (Ovibos, Praeovibos, Soergelia, etc) are also part of this subfamily, but they will be discussed in the next article.
First, the ibex. The genus Capra was once found across every mountain range and rocky habitat in central and southern Europe. The Anatolian subspecies of the bezoar ibex (Capra aegagrus aegagrus), the smallest of the European ibex species at a maximum weight of ~90 kg, is found in the rocky habitats of Turkey and adjacent Armenia, Azerbaijan, and Georgia, in addition to several countries not generally considered to be part of the European continent. This taxon represents the ancestral stock from which all domestic goats descend, and is still found in a large portion of its previous distribution. Despite this, it is considered vulnerable by the IUCN and has suffered population reductions in some regions due to poaching, trophy hunting, habitat loss, and hybridization with its domestic relatives. These factors have led to its complete extirpation from several areas, including most of western and northern Turkey. Nearby, in the Caucasus mountains, including Georgia and the adjacent regions of Russia, the Caucasian ibex is found. Traditionally this species was split into two, one for the western part of the mountain range and one for the east, but this has since been reconsidered so that that they are now considered subspecies: the western Caucasian ibex (Capra caucasica caucasica) and the eastern Caucasian ibex (Capra caucasica cylindricornis). At a maximum weight of ~140 kg, this is the largest of the European ibex species. While the western subspecies is considered endangered, the eastern is listed only as near-threatened. This species has the smallest original distribution of the four European ibex species, and consequently has the fewest opportunities for reintroduction. The protection of its existing habitat is very important to it continued survival.
The Alpine ibex, of which there are no recognized subspecies and which is considered to be least concern by the IUCN, seems to have suffered the greatest range reduction out of these four species. Present only in the Alps today, this species was also present in the Tatras, Balkans, and Dinaric mountain ranges until the mid-Holocene, and the Carpathian and Apennine mountain ranges until at least the late Pleistocene. Extirpated from everywhere but the French and Italian Alps by the early twentieth century, the ibex has since been reintroduced to the alpine regions of Austria, Germany, and Slovenia. Reintroduction attempts have also been made in Slovakia to replace the extinct Tatras population, but the project failed due to the animals being not only of Alpine stock, but also of Anatolian and even Nubian (Capra nubiana) individuals. At the time these ibex varieties were considered to be subspecies of each other, and it was thought that a broad genetic base would increase the likelihood of a successful introduction. However, the hybrids molted at the wrong time of the year, due to the adaptations inherited from their more desert-adapted ancestors, and the population did not survive the winter. Future attempts should use only non-hybridized C. ibex. A population also exists in Bulgaria, imported for sport. These animals are often treated as alien, but their Holocene fossil record in the area suggests that they are better thought of as a reintroduced species. Further reintroductions to the Balkans and Dinarides should be a part of any rewilding projects in those areas. I would also put forward that the Apennines and Carpathians should be considered for reintroductions as well.
The last of the European ibex species is the Iberian ibex. In modern times there have been four subspecies of this ibex living in the Iberian peninsula. These were the eastern Spanish ibex (Capra pyrenaica hispanica), the Portuguese ibex (Capra pyrenaica lusitanica), the Pyrenean ibex (Capra pyrenaica pyrenaica), and the western Spanish ibex (Capra pyrenaica victoriae). Of these, the eastern variety is considered least concern, the western is vulnerable, and the Portuguese and Pyrenean are extinct, the former since the late nineteenth century, and the latter since the early twenty-first century. Both were victims of hunting, competition with livestock, and habitat loss. The Pyrenean subspecies is notable for having gone extinct twice: first in 2000 when the last wild individual was hit by a fallen tree, and again in 2003 when a kid was cloned from material taken from this individual, only to die after several minutes. It is my opinion that future cloning efforts should be reserved for species with more unique evolutionary/ecological histories, and that the best option for the Pyrenean ibex is to create new populations using another subspecies, something that has already been considered by French organizations. It may be possible to integrate the genetic material of the Pyrenean subspecies into these populations in the future. The Portuguese subspecies is in the process of being replaced by the western ibex subspecies through natural dispersal and translocation.
Moving on to the chamois group. The Pyrenean chamoi has three living subspecies, all of which are considered least concern by the IUCN, these are: the nominate subspecies (Rupicapra pyrenaica pyrenaica), which occupies the Pyrenean mountains of southwestern France and north-eastern Spain, the Cantabrian chamois of north-western Spain (Rupicapra pyrenaica parva), and the Abruzzo chamois (Rupicapra pyrenaica ornata) of the Italian Apennines. Fossil records indicate that the Pyrenean chamois used to occupy the entirety of the Iberian peninsula until they were extirpated from Portugal and most of Spain in the middle Holocene. It is unclear if these populations were referable to the Cantabrian subspecies or to some extinct group, but either way the possibility for a redistribution of the species across the peninsula could be possible, especially with the increasingly low population densities in some areas of Iberia. The other chamois species has a much larger range and a greater diversity of subspecies. The nominate subspecies (Rupicapra rupicapra rupicapra) is found in the Alps, and there are also Balkan (Rupicapra rupicapra balcanica), Carpathian (Rupicapra rupicapra carpatica), Carthusian (Rupicapra rupicapra cartusiana), Anatolian (Rupicapra rupicapra asiatica), and Caucasian subspecies (Rupicapra rupicapra caucasica), in addition to a critically-endangered subspecies from the Tatras (Rupicapra rupicapra tatrica). Populations of all these taxa have undergone reductions in their distributions, and have become heavily fragmented by habitat loss. A priority for their recovery will be to improve connectivity between their pockets of occurrence.
As for the third genus, Ovis, the history in Europe is a little more complicated. The current representative of the wild sheep in Europe is the European mouflon (Ovis orientalis musimon). This population descends from wild sheep found on the islands of Corsica and Sardinia, which were later imported to the mainland for hunting purposes, where they have since become very widespread. The problem is that the original stock were not as wild as originally thought, being the descendants of an early variety of domestic sheep (Ovis orientalis aries), which were able to go feral on these islands only due to the lack of large predators. They display very domestic behaviours, preferring lowland habitats to rocky highlands, and being very easily taken by predators, so much so that when predators have returned to certain areas in the past, the local mouflon population has disappeared completely. This needs to be considered if mouflon are to be used in rewilding projects. One approach is to use one of the truly wild subspecies instead, such as the wild sheep of the Transcaucasian region (Ovis orientalis gmelini) which should be better adapted to predation and to harsh terrain. This subspecies is threatened, and expanding its distribution would certainly help in its conservation. We would have to be prepared for the possibility of hybridization with existing populations of the European variety, but this is to be expected, and it is possible that a combination of the two varieties would be quite suitable for multiple European regions, assuming that natural selection will favour crossbreeds which inherit wildtype behaviours. The original distribution of mouflon on the mainland included the Balkan and Italian peninsula, in addition to Turkey and Transcaucasia, but fossils of the genus Ovis have been found outside of this region as well, allowing for the possibility of their use in rewilding projects in most of the European mountain ranges.
The last genus I will be discussing in this article is one that no longer occurs in Europe, and that is Hemitragus, today represented only by the Himalayan tahr (Hemitragus jemlahicus). From the mid-late Pleistocene there was another species in this genus, known as the European tahr (Hemitragus bonali). This species would have coexisted with the other three genera, and had a range that included all of the same mountain ranges. There even exists cave art that appears to depict a tahr (alongside an ibex), displaying many of the features that define the living species, such as short horns and a thick mane of fur around the neck. Native only to the Himalayas today, the tahr has become an invasive species in many areas where it has been imported for game hunting, including Argentina, New Zealand, South Africa, and the southern United States. This ability to adapt to a range of habitats speaks well for their potential introduction to Europe as a replacement for their extinct relatives. It is unknown exactly how they would interact with the other Caprines, but its relative did so seemingly without competitive exclusion for hundreds of millenia, and the Himalayan species is sympatric with several related species, such as (depending on the region) bharal (Pseudois nayaur), argali (Ovis ammon), goral (Nemorhaedus goral), serow (Capricornis thar), and markhor (Capra falconeri). The ibex, mouflon, and chamois seem to avoid competition through living at different altitudes and through differences in the amount of browse or graze taken by each species. Presumably the European tahr would have fit into this dynamic somehow, but more research will be necessary to determine how, and if the living species would have similar interactions with its environment.
Populations of all four genera would be predated on by wolves (Canis lupus), bears (Ursus arctos), and lynx (Lynx lynx). Their re-establishment would also be an important preliminary step in the reintroduction of the leopard (Panthera pardus) to European rewilding areas. Human hunting of goat-like species is already a huge industry, and expansions and introductions would only reinvigorate that industry, with the understanding that offtake has to be sustainable. Wild meat and leather could be sourced from the offtake as well. These are also all species that people would potentially enjoy seeing in natural areas, and which could further stimulate ecotourism. Their ability to traverse uneven terrain will make them especially important for fighting succession and stimulating nutrient cycling in high altitude regions where larger herbivores like red deer and bison are less able to traverse the terrain.
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