Wallowing in animals is comfort behaviour during which an animal rolls about or lies in

mud Mud (, or Middle Dutch) is loam, silt or clay mixed with water. Mud is usually formed after rainfall or near water sources. Ancient mud deposits hardened over geological time to form sedimentary rock such as shale or mudstone (generally cal ...

water Water is an inorganic compound with the chemical formula . It is a transparent, tasteless, odorless, and Color of water, nearly colorless chemical substance. It is the main constituent of Earth's hydrosphere and the fluids of all known liv ...

snow Snow consists of individual ice crystals that grow while suspended in the atmosphere—usually within clouds—and then fall, accumulating on the ground where they undergo further changes. It consists of frozen crystalline water througho ...

. Some definitions include rolling about in dust, however, in

ethology Ethology is a branch of zoology that studies the behavior, behaviour of non-human animals. It has its scientific roots in the work of Charles Darwin and of American and German ornithology, ornithologists of the late 19th and early 20th cen ...

this is usually referred to as

dust bathing Dust bathing (also called sand bathing) is an animal behavior characterized by rolling or moving around in dust, dry earth or sand, with the likely purpose of removing parasites from fur, feathers or skin. Dust bathing is a Comfort behaviour in ...

. Wallowing is often combined with other behaviours to fulfil its purpose; for example, elephants will often blow dirt over themselves after wallowing to create a thicker "coating", or pigs will allow the mud to dry before rubbing themselves on a tree or rock to remove

ectoparasites Parasitism is a close relationship between species, where one organism, the parasite, lives (at least some of the time) on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The en ...

stuck in the mud.

Functions

Many functions of wallowing have been proposed although not all have been tested by rigorous scientific investigation. Proposed functions include: *Thermoregulation –

domestic pigs The pig (''Sus domesticus''), also called swine (: swine) or hog, is an Omnivore, omnivorous, Domestication, domesticated, even-toed ungulate, even-toed, hoofed mammal. It is named the domestic pig when distinguishing it from other members of ...

(''Sus scrofa''), great

Indian rhinoceros The Indian rhinoceros (''Rhinoceros unicornis''), also known as the greater one-horned rhinoceros, great Indian rhinoceros or Indian rhino, is a species of rhinoceros found in the Indian subcontinent. It is the second largest living rhinocer ...

(''Rhinoceros unicornis''),

warthogs ''Phacochoerus'' is a genus in the family Suidae, commonly known as warthogs (pronounced ''wart-hog''). They are pigs who live in open and semi-open habitats, even in quite arid regions, in sub-Saharan Africa. The two species were formerly cons ...

(''Phacochoerus aethiopicus''),

elephants Elephants are the Largest and heaviest animals, largest living land animals. Three living species are currently recognised: the African bush elephant (''Loxodonta africana''), the African forest elephant (''L. cyclotis''), and the Asian ele ...

(family Elephantidae) *Providing a sunscreen – pigs, warthogs, elephants *Male-male conflict social behaviour –

elk The elk (: ''elk'' or ''elks''; ''Cervus canadensis'') or wapiti, is the second largest species within the deer family, Cervidae, and one of the largest terrestrial mammals in its native range of North America and Central and East Asia. ...

(''Cervus elaphus''),

European bison The European bison (: bison) (''Bison bonasus'') or the European wood bison, also known as the wisent ( or ), the zubr (), or sometimes colloquially as the European buffalo, is a European species of bison. It is one of two extant species of bi ...

(''Bison bonasus''), deer *Removal of

–

white rhinoceros The white rhinoceros, also known as the white rhino or square-lipped rhinoceros (''Ceratotherium simum''), is the largest extant species of rhinoceros and the most Sociality, social of all rhino species, characterized by its wide mouth adapted f ...

(''Ceratotherium simum''), American bison (''Bison bison''), warthog *Social cohesion –

American bison The American bison (''Bison bison''; : ''bison''), commonly known as the American buffalo, or simply buffalo (not to be confused with Bubalina, true buffalo), is a species of bison that is endemic species, endemic (or native) to North America. ...

*Relief from

moulting In biology, moulting (British English), or molting (American English), also known as sloughing, shedding, or in many invertebrates, ecdysis, is a process by which an animal casts off parts of its body to serve some beneficial purpose, either at ...

–

, elephant seals (genus ''Mirounga'') *Relief from biting insects –

tamaraw The tamaraw or Mindoro dwarf buffalo (''Bubalus mindorensis'') is a small buffalo belonging to the family Bovidae. It is endemic to the island of Mindoro in the Philippines, and is the only endemic Philippine bovine. It is believed, however, ...

(''Bubalus mindorensis''), American bison,

tapirs Tapirs ( ) are large, herbivorous mammals belonging to the family Tapiridae. They are similar in shape to a Suidae, pig, with a short, prehensile nose trunk (proboscis). Tapirs inhabit jungle and forest regions of South America, South and Centr ...

(''Tapirus bairdii''), warthog, elephants *Play in young animals – American bison *Skin maintenance (preventing dehydration) – hippopotamus (''Hippopotamus amphibius'') *Camouflage – warthog *

Scent-marking In ethology, territory is the sociographical area that an animal consistently defends against conspecificity, conspecific competition (biology), competition (or, occasionally, against animals of other species) using agonistic behaviors or (less ...

– Some animals urinate in a wallow before entering and rolling in it, presumably as a form of scent-marking behaviour *Skin microbiome selection – Horses

Domestic pigs

Pigs lack functional sweat glands and are almost incapable of panting. To thermoregulate, they rely on wallowing in water or mud to cool the body. Adult pigs under natural or free-range conditions can often be seen to wallow when air temperature exceeds 20 °C. Mud is the preferred substrate; after wallowing, the wet mud provides a cooling, and probably protecting, layer on the body. When pigs enter a wallow, they normally dig and root in the mud before entering with the fore-body first. They then wriggle the body back and forth, and rub their faces in the mud so all of the body surface is covered. Before they leave the wallow, they often shake their heads and body, often finishing with rubbing against a tree or a stone next to the wallow. When indoors and hot, domestic pigs often attempt to wallow on wet floor surfaces and in the dunging areas. Although temperature regulation seems to be the main motivation for wallowing in pigs, they will still wallow in colder weather. While many have suggested that pigs wallow in mud because of a lack of sweat glands, pigs and other wallowing animals may have not evolved functional sweat glands because wallowing was a part of their behavioural repertoire.Bracke, M. (2011)
Review of wallowing in pigs: Description of the behaviour and its motivational basis
Applied Animal Behaviour Science, 132: 1-13 Pigs are genetically related to animals such as

hippopotamus The hippopotamus (''Hippopotamus amphibius;'' ; : hippopotamuses), often shortened to hippo (: hippos), further qualified as the common hippopotamus, Nile hippopotamus and river hippopotamus, is a large semiaquatic mammal native to sub-Sahar ...

and

whales Whales are a widely distributed and diverse group of fully Aquatic animal, aquatic placental mammal, placental marine mammals. As an informal and Colloquialism, colloquial grouping, they correspond to large members of the infraorder Cetacea ...

. It has been argued that wallowing behaviour and the desire to be in shallow, murky water could have been a step to the evolution of whales and other marine mammals from land-dwelling mammals.

Sumatran rhinoceros

The Sumatran rhino (''Dicerorhinus Sumatrensis'') spends a large part of its day wallowing. When mud holes are unavailable, the rhino will deepen puddles with its feet and horns. One 20-month study of wallowing behaviour found they will visit no more than three wallows at any given time. After two to 12 weeks using a particular wallow, the rhino will abandon it. Typically, the rhino will wallow around midday for two to three hours at a time before foraging for food. Although in zoos the Sumatran rhino has been observed wallowing less than 45 minutes a day, the study of wild animals found 80–300 minutes per day spent in wallows. Captive individuals deprived of adequate wallowing have quickly developed broken and inflamed skins,

suppuration Pus is an exudate, typically white-yellow, yellow, or yellow-brown, formed at the site of inflammation during infections, regardless of cause. An accumulation of pus in an enclosed tissue space is known as an abscess, whereas a visible collec ...

s, eye problems, inflamed nails, hair loss and have eventually died.

Deer

Many deer perform wallowing, creating wallow sites in wet depressions in the ground, eventually forming quite large sites (2–3 m across and up to 1 m deep). However, it has been claimed that only some species of deer wallow;

red deer The red deer (''Cervus elaphus'') is one of the largest deer species. A male red deer is called a stag or Hart (deer), hart, and a female is called a doe or hind. The red deer inhabits most of Europe, the Caucasus Mountains region, Anatolia, Ir ...

(''Cervus elaphus'') particularly like to wallow but

fallow deer Fallow deer is the common name for species of deer in the genus ''Dama'' of subfamily Cervinae. There are two living species, the European fallow deer (''Dama dama''), native to Europe and Anatolia, and the Persian fallow deer (''Dama mesopotamic ...

(''Dama dama''), for example, do not wallow. Even within the red deer species, there is variation between sub-species and breeds in wallowing behaviour. For example, although wapiti do wallow, they and crossbreds are less inclined to wallow than European red deer.

References

External links