miércoles, 22 de marzo de 2023

Turkmen Corsac Fox (Vulpes corsac turcmenicus)

THE TURKMEN CORSAC FOX

It is the southernmost subspecies of corsac within its range. They occupy most of the southern plains of central Asia. Like the other corsac subspecies, they avoid high altitudes and prefer broad steppes. Like their Caucasus counterparts, they differ little from the common corsac fox, differing only in their generally smaller size, and the bit whiter fur in winter.

About the species

The Turkmen subspecies are the smallest corsac subspecies, with shorter, coarser winter fur of dirty-grayish color and reddish tones. There are wide zones of transition between subspecies.

For a fox, it has small teeth and a wide skull. It has a number of scent glands, some of which produce pungent odors, although not so extreme as those found in some other Vulpes species. As in other corsac foxes, are reported to bark during hunting or when threatening rivals, and to use higher pitch yelps or chirps as alarm calls or social greetings.

Reproduction and behavior

Gestation: 52-62 days.
Young per birth: around 5.
Weaning: 28 days.
Sexual maturity: 9 months.
Life span: Around 9 years.
Breeding season: January to March.

Diet and interaction with the environment

The diet of this subspecies is mainly omnivorous, although it focuses on small rodents, as well as insects and fruits. A characteristic of the turkmen foxes is that they can go without water for extensive periods of time, usually longer than other corsac foxes.

It has no defended territory, and unlike other fox species, sometimes they forms packs. Daytime activity is most frequent at times when food is needed and when food is scarce, during the winter. It digs its own dens, usually shallow, but also the burrows of other animals, such as marmots, groundhogs or badgers. Dens can have multiple entrances, but are usually one meter deep. The burrow is shared between social packs, with dens and connecting holes. As corsac foxes, they are excellent climbers, but not good runners, and could be caught easily by a dog.

Habitat:

Native to Turkmenistan (as the name of this subspecies suggests), Uzbekistan, lowest regions of Kyrgyzstan and Tadjikistan, as well as most northern parts of Iran and Afghanistan, and southern Kazakhstan. There are a few indications of sightings in China, although rare, it is possible that its range extends to the westernmost limits of the country. They mostly inhabit grassland steppes, semi-deserts and deserts, avoiding mountains, forested areas, dense vegetation and cultivated lands.

Conservation status: There are no estimates of population size and few details are known about the characteristics of regional populations, but it is considered widespread and common. As of 2014, the corsac fox species are listed as least concern in the IUCN Red List.

Physiognomic information:

Body length: around 40 cm
Tail length: around 20 cm
Height: usually less than 30 cm
Weight: 1.6-2.1 kg
Skull: around 10 cm

Taxonomy:

Gallery:

Because of its similarity in appearance to the common corsac fox, some of the images may be erroneous. That's why I haven't found any videos about this subspecies either, if you think you have any image or video of the Vulpes corsac turcmenicus let me know in the comments or contact me on my social networks (@etzharai).

Sources:

Canids of the World

Global Biodiversity Information Facility (GBIF)

Integrated Taxonomic Information System (ITIS)

Canidae (in Russian)

martes, 21 de marzo de 2023

Caucasus Corsac Fox (Vulpes corsac kalmykorum)

THE CAUCASUS CORSAC FOX

This subspecies of the Corsac fox lives in the westernmost part of the Central Asian steppes. Unlike the Vulpes corsac corsac, the Caucasian corsac fox does not face such abrupt temperature changes through the year, so its winter coat is not as fluffy as other species. They are also a bit smaller than common corsac foxes.

About the species

A small-sized fox, with relatively broad ears, a short pointy face, and a short tail. Coat is short, buff to straw gray in summer, shading to rufous, while in winter it is grayish white. Forehead is darker with pale markings around mouth, chin, throat and groin. A patch of dark fur extends from the inner corner of each eye down the sides of the muzzle to the nose. Ears are large and broad. Legs are light yellow anteriorly and rusty yellow laterally. Winter coat is silky and soft, straw gray in color, with a darker line running down the back. Teeth are small. Tail is dark ocher to gray brown, with a dark spot about 6-7 cm from the base in the supracaudal gland, and a black tip. Females are similar to males. Newborns are light brown, with a monocolored tail.

Reproduction and behavior

Gestation: 50-60 days.
Young per birth: 2-6.
Weaning: 28 days.
Sexual maturity: 9 months.
Life span: Around 9 years.
Breeding season: January to March.

Several males run behind a female in estrus and fights often occur between the males. Monogamy is established when the females chooses a male. Earliest births are in mid-March, but most occur in April. Males participate in raising and feeding young but stay in another den or just outside the natal den. They will often take burrows of other animals to raise their young in. Young are born blind and with closed auditory meatuses. Juveniles emerge from dens in mid-May. Young grow rapidly, reach adult size in 4 months. Social behavior: Family groups.

Diet and interaction with the environment

Opportunistic forager and hunter; small to medium-sized vertebrates (vole, gerbil, jerboa, hamster, squirrel, pika, bustard), insects, and fruits. They may scavenge carcasses. Can go without water for extensive periods of time. Main predators: Wolf, Red Fox, Dog, eagles, owls. Mainly nocturnal, but may be seen during twilight and daytime hours. Very social, living in large groups with several burrows interconnected. It hunts alone or in small packs. Territory sizes are variable, from 1.9 to 11.4 km2.

They are nomadic and do not keep a fixed home range, and will migrate when food is sparse, ranging from 50 to 600 km. They scent mark with urine and feces near natal dens to maintain territories and as a way of intraspecific communication. As with the other Corsac foxes, they lack the musky odor of other Vulpine foxes. They are excellent climbers, but slow runners. The most common vocalization is barking.

Habitat:

They are found mainly in the regions between the Caspian Sea and the Aral Sea, in the western steppes, extending over much of the northern Caucasus region, from which they are named (or the Kalmykia region in Russia). They avoid high altitudes, so it would be very rare to see one of these species on the southern slopes of the Caucasus mountain range. Since the drying up of the Aral Sea, is believed that they have left the region for more fertile regions in the west.

Native to southern Russia, western Kazakhstan, northwestern Uzbekistan and northern Turkmenistan. The region where they are least documented lately is the area bordering Uzbekistan and Turkmenistan.

Physiognomic information:

Body length: 45-50 cm
Tail length: 15-30 cm
Height: around 30 cm
Weight: 1.9-2.4 kg
Skull: 9-11 cm

Taxonomy:

Gallery:

Because of its similarity in appearance to the common corsac fox, some of the images may be erroneous. That's why I haven't found any videos about this subspecies either, if you think you have any image or video of the Vulpes corsac kalmykorum let me know in the comments or contact me on my social networks (@etzharai).

Sources:

Inaturalist

Canids of the World

Global Biodiversity Information Facility (GBIF)

Integrated Taxonomic Information System (ITIS)

sábado, 18 de marzo de 2023

Common Corsac Fox (Vulpes corsac corsac)

THE CORSAC FOX

The corsac fox (Vulpes corsac), also known simply as corsac (and also known as the steppe fox), is a medium-sized fox found in steppes, semi-deserts and deserts in Central Asia, ranging into Mongolia and northern China. Since 2004, it has been classified as least concern by IUCN, but populations fluctuate significantly, and numbers can drop tenfold within a single year. The word "corsac" is derived from the Russian name for the animal, "korsák" (корса́к), derived ultimately from Turkic "karsak".

About the species

The Corsac fox is a medium-sized fox, it has grey to yellowish fur over much of the body, with paler underparts and pale markings on the mouth, chin, and throat. During the winter, the coat becomes much thicker and silkier in texture, and is straw-grey in colour, with a darker line running down the back.

For a fox, it has small teeth and a wide skull. This species can climb trees and has been domesticated in the past. It is reported to have keen eyesight and hearing and an acute sense of smell. It has a number of scent glands, some of which produce pungent odors, although not so extreme as those found in some other Vulpes species. Corsac foxes are reported to bark during hunting or when threatening rivals, and to use higher pitch yelps or chirps as alarm calls or social greetings.

Reproduction and behavior

Gestation: 52-60 days.
Young per birth: 2-6, even up to 10.
Weaning: 28 days.
Sexual maturity: 9-10 months.
Life span: Around 9 years.
Breeding season: The mating season starts in January and ends in March.

Males will initially fight for access to females, but eventually establish a monogamous bond, and assist in the raising of their young. The mother initially creates a birthing den, which is sometimes shared with other pregnant females, but moves her young to new burrows several times after they are born.

Typically, two to six young are born after a gestation period of 52 to 60 days, although cases of ten kits being born in a single litter have been reported. Newborn kits weigh around 60 g, and have fluffy, light brown fur that turns yellowish as they age. They are born blind, and open their eyes at around two weeks of age; they begin to eat meat at four weeks, and emerge from the den shortly after. Corsac foxes reach sexual maturity within 9 to 10 months and reproduce in the second year of life. They live up to 9 years in the wild.

Diet and interaction with the environment

As an adaption to the arid climate in which they live, corsac foxes can forego food and water for extended periods of time. The corsac fox is an opportunistic forager and hunter. Its diet varies throughout its range, but consists foremost of small and medium-sized vertebrates, insects and small rodents, such as voles, gerbils, jerboas, hamsters, and ground squirrels. It also feeds opportunistically on larger prey including hares and pikas. It scavenges for carrion and human refuse as well. Although predominantly carnivorous, it occasionally eats fruit and other vegetation, especially during winter when availability of animal prey is low. Natural predators of the corsac fox include gray wolf, Eurasian eagle-owl, eagles, and (rarely, for pups) the upland buzzard. Golden eagles are major predators, with 38% of remains found belonging to the corsac fox at a golden eagle nest in Mongolia.

The Corsac fox is a nocturnal and nomadic hunter of the steppes. It does not have a defended territory, and unlike some foxes, sometimes forms packs. Diurnal activity is more common at times when kits need to be fed and when food is scarce, as during the winter. Because it cannot hunt in deep snow, it either shelters in dens during harsh weather, or, in the northern parts of its range, it migrates up to 600 km (370 mi) south in the winter. It has been reported to follow herds of local antelope, relying on them to compress the snow as they pass. It digs its own dens, which are generally shallow, but also takes over the burrows of other animals, such as marmots, ground squirrels, or badgers. Dens may have several entrances, but are usually less than 1 metre (3 ft 3 in) deep. The burrow is shared between the social packs, with several dens and connecting holes, which resemble "corsac cities". They are excellent climbers, but are rather slow runners and could be caught easily by a dog. While they are reported to be nocturnal in the wild, in captivity they are very active during the day.

Habitat:

Corsac foxes live in the steppes and semidesert of central and northeast Asia. They are found throughout Kazakhstan, Uzbekistan, and Turkmenistan, and through all except the northernmost regions of Mongolia. In the south, their range extends into the more northern parts of Iran, Tajikistan, Kyrgyzstan, Afghanistan, and China, and they can also be found in neighbouring regions of Russia.

These foxes inhabit open grassy steppes and semideserts, and avoid dense vegetation and mountainous regions. True deserts with drifting sands are also avoided, as are snowfields more than about 15 cm (6 in) deep. Corsac foxes generally stay far away from human disturbances.

Conservation status: Least Concern. Regional status: Endangered in Iran, Vulnerable in China and Near Threatened in Mongolia. There are no estimates of population size and few details are known about the characteristics of regional populations, but it is considered widespread and common.

The major threat posed to the corsac fox is poaching, as it is a valuable fur-bearing species and has been harvested by humans since the Bronze Age for subsistence and commercial purposes. It is a slow runner and therefore easily caught by hunters; the population has been reduced in areas where it has been heavily hunted for its fur. Traditionally, the corsac fox is often hunted with trained domestic dogs, saker falcons, and golden eagles, as well as caught with traps set at burrow entrances, leghold traps, and firearms. In the late 19th century, up to 10,000 foxes were killed annually for pelt trade. The general population remains healthy, however, as the corsac fox has proven to be able to withstand great hunting pressures, and their habitats remain intact due to the low human population density in its range.

Other threats include overgrazing by livestock and landscape development; the decline of marmots may also impact the species in some areas, as it often uses marmot burrows as daytime resting locations. The other main threat is natural disasters, which can cause the numbers of foxes to drop 90% in some areas, but the population often recovers quickly. As of 2014, the corsac fox is listed as least concern in the IUCN Red List.