By Nipper Read
Vipera berus is a relatively small species of viper, with a massive distribution; it is in fact, the snake species with the largest distribution of all snakes, even extending into the arctic circle. Three sub species occur, although there is debate as to whether there are more sub species or in fact separate species within the complex.
Vipera berus berus
Appearance: This is a small, slender viper with a relatively small head , distinct from the body. The average length ranges between 60 -85 cm but larger adults may occur occasionally. There is a notable difference between male and females, with females growing bigger on average and being more solidly built.
The colouration is usually the iconic silver grey with black zig zag markings or the bronze, brown with zigzag markings often associated with females. However there are many different colour variations, with blue or melanistic individuals being occasionally encountered. Like all vipers the pupil is horizontal.
Distribution: Vipera berus has a vast distribution, occurring from the UK, where it is the only venomous snake, throughout mainland Europe, including Scandinavia and into the Amur region of Asia. Vipera berus berus occurs from sea level to 3000m above sea level.
Habitat: Vipera berus berus occurs in a broad range of habitat, in the UK the adder is associated with chalk down land, and dry scrub habitat, in Europe it is found within pine forests, damp meadows and coastal dunes.
Biology: Vipera berus berus is a reptile, amphibian and mammal feeder. Neonates feed on small frogs, juvenile lizards and potentially insects. Adults feed on larger lizards and frogs as well as mice and voles.
Males emerge from hibernation in late February, and aggregate around the hibernaculum. Females emerge slightly later. Mating occurs in June with females giving birth in late august or September. Males can be seen duelling with each other prior to mating in the same way as Vipera aspis and Crotalus.
Venom: The LD50 is 0.55 mg/kg in mice, which although relatively low, has caused a number of deaths throughout Europe. Local symptoms include immediate and intense pain, followed after a few minutes by swelling and a tingling sensation. Reddish lymphangitic lines and bruising may appear, and the whole limb can become swollen and bruised within 24 hours. Swelling may also spread to the trunk, and with children, throughout the entire body.
Systemic symptoms resulting from anaphylaxis can be dramatic. These may appear within 5 minutes post bite, or can be delayed for many hours. Such symptoms include nausea, retching and vomiting, abdominal colic and diarrhoea, incontinence of urine and faeces, sweating, fever, vasoconstriction, tachycardia, lightheadedness, loss of consciousness, blindness, and shock.
Vipera Berus bosniensis.
Appearance: Vipera berus bosniensis differs greatly in appearance to Vipera berus berus, There are obvious differences in terms of colouration, patterning and scaleation. The morphological differences and the different venom composition lead many authors to believe that this subspecies is in fact a separate species in its own right. In Vipera berus bosniensis the zigzag pattern is largely replaced by cross barring with a noticeably lighter, silver grey background, this colouration occurs in females as well as males, unlike the nominate Vipera berus berus form. There are lowland populations where the background colour is predominantly brown.
Distribution: Vipera berus bosniensis occurs in Southern Slovenia, Bulgaria, Montenegro, Bosnia and Greece.
Habitat: Vipera berus bosniensis was originally thought to be a completely montane species, occurring on south facing slopes, often with low juniper bushes, and montane meadows. However populations have been recorded in Slovenia in lowland marshland habitat.
Biology: The biology of Vipera berus bosniensis is similar to that of Vipera berus berus, however montane forms will emerge from hibernation later in the year due to the lower temperatures at altitude.
Venom: The venom of Vipera berus bosniensis differs from that of Vipera berus berus in the fact that it contains a neurotoxic element not found in the nominate form.
Vipera berus sachaliensis
Distribution: Russian Far East , Amur, Oblast, Primorskye Kray, Khabarovk Kray, Sakhalin, North Korea, Northeast China.
Appearance: As Vipera berus berus, but somewhat stockier.
Habitat: As Vipera berus berus.
Biology: As Vipera berus berus.
Venom: As Vipera berus berus.
Associated species: Several other species have previously been included in the Vipera berus complex: Vipera seonei, the Spanish Adder, now a full species, found in mainland Spain. Vipera Nikolskii, Nickolski’s Adder, often melanistic, debatably a full species, found in Moldova and Ukraine and Vipera barani, Baron’s Adder, currently a full species from Turkey.
Captive husbandary of the Vipera berus species
Vipera berus is a very sought after species in the hobby, due to the striking pattern and small size, however this species does not do well in captivity. It is extremely rare for a wild caught specimen to acclimate to captive care. The temperature, humidity and seasonal feeding required by this species is extremely hard to reproduce in captivity.
For best success with these species a large outdoor terraria seems to work best, with captive bred examples of this species. The terraria will need suitable basking sites, hide areas, hibanecular, and a water source, ideally in the form of a small pond. Live amphibians, lizards and mice make suitable prey items.
If keeping Vipera berus indoors, a vivarium larger than that for other vipers of the same size is required. Vipera berus is a very mobile species. Clean water and good ventilation is essential. As with all European vipers, high quality UV is a must for maintaining health in the vivarium. Vipera berus is an iconic species in Europe, embedded in folk lore and protected throughout much of its range. It still remains one of my favourite species to photograph and observe in the wild.
Their range is HUGE!