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In
ethology Ethology is the scientific study of animal behaviour, usually with a focus on behaviour under natural conditions, and viewing behaviour as an evolutionarily adaptive trait. Behaviourism as a term also describes the scientific and objectiv ...
, territory is the sociographical area that an
animal Animals are multicellular, eukaryotic organisms in the Kingdom (biology), biological kingdom Animalia. With few exceptions, animals Heterotroph, consume organic material, Cellular respiration#Aerobic respiration, breathe oxygen, are Motilit ...
consistently defends against
conspecific Biological specificity is the tendency of a characteristic such as a behavior or a biochemical variation to occur in a particular species. Biochemist Linus Pauling stated that "Biological specificity is the set of characteristics of living organ ...
competition Competition is a rivalry where two or more parties strive for a common goal which cannot be shared: where one's gain is the other's loss (an example of which is a zero-sum game). Competition can arise between entities such as organisms, indivi ...
(or, occasionally, against animals of other
species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...
) using agonistic behaviors or (less commonly) real physical
aggression Aggression is overt or covert, often harmful, social interaction with the intention of inflicting damage or other harm upon another individual; although it can be channeled into creative and practical outlets for some. It may occur either reacti ...
. Animals that actively defend territories in this way are referred to as being territorial or displaying territorialism. Territoriality is only shown by a minority of species. More commonly, an individual or a group of animals occupies an area that it habitually uses but does not necessarily defend; this is called its
home range A home range is the area in which an animal lives and moves on a periodic basis. It is related to the concept of an animal's territory which is the area that is actively defended. The concept of a home range was introduced by W. H. Burt in 1943. He ...
. The home ranges of different groups of animals often overlap, and in these overlap areas the groups tend to avoid each other rather than seeking to confront and expel each other. Within the home range there may be a ''core area'' that no other individual group uses, but, again, this is as a result of avoidance.


Function

The ultimate function of animals inhabiting and defending a territory is to increase the individual fitness or
inclusive fitness In evolutionary biology, inclusive fitness is one of two metrics of evolutionary success as defined by W. D. Hamilton in 1964: * Personal fitness is the number of offspring that an individual begets (regardless of who rescues/rears/supports them ...
of the animals expressing the behaviour. Fitness in this biological sense relates to the ability of an animal to survive and raise young. The proximate functions of territory defense vary. For some animals, the reason for such protective behaviour is to acquire and protect food sources, nesting sites, mating areas, or to attract a mate.


Types and size

Among birds, territories have been classified as six types. *Type A: An 'all-purpose territory' in which all activities occur, e.g. courtship, mating, nesting and foraging *Type B: A mating and nesting territory, not including most of the area used for foraging. *Type C: A nesting territory which includes the nest plus a small area around it. Common in colonial waterbirds. *Type D: A pairing and mating territory. The type of territory defended by males in lekking species. *Type E: Roosting territory. *Type F: Winter territory which typically includes foraging areas and roost sites. May be equivalent (in terms of location) to the Type A territory, or for a migratory species, may be on the wintering grounds. Reports of territory size can be confused by a lack of distinction between home range and the defended territory. The size and shape of a territory can vary according to its purpose, season, the amount and quality of resources it contains, or the geography. The size is usually a compromise of resource needs, defense costs, predation pressure and reproductive needs. Some species of
squirrels Squirrels are members of the family (biology), family Sciuridae, a family that includes small or medium-size rodents. The squirrel family includes tree squirrels, ground squirrels (including chipmunks and prairie dogs, among others), and flyi ...
may claim as much as of territory. For
European badger The European badger (''Meles meles''), also known as the Eurasian badger, is a badger species in the family Mustelidae native to almost all of Europe. It is classified as least concern on the IUCN Red List as it has a wide range and a large stabl ...
s, a home range may be as small as in a good rural habitat, but as large as in a poor habitat. On average, a territory may be approximately , with main setts normally at least apart. In urban areas, territories can be as small as , if they can obtain enough food from bird tables,
food waste Food loss and waste is food that is not eaten. The causes of food waste or loss are numerous and occur throughout the food system, during production, processing, distribution, retail and food service sales, and consumption. Overall, about o ...
or artificial feeding in suburban gardens.
Spotted hyena The spotted hyena (''Crocuta crocuta''), also known as the laughing hyena, is a hyena species, currently classed as the sole extant member of the genus ''Crocuta'', native to sub-Saharan Africa. It is listed as being of least concern by the IUC ...
s (''Crocuta crocuta'') have highly variable territory sizes, ranging from less than in the
Ngorongoro Crater The Ngorongoro Conservation Area (, ) is a protected area and a UNESCO World Heritage Site located in Ngorongoro District, west of Arusha City in Arusha Region, within the Crater Highlands geological area of northern Tanzania. The area is nam ...
to over in the
Kalahari The Kalahari Desert is a large semi-arid sandy savanna in Southern Africa extending for , covering much of Botswana, and parts of Namibia and South Africa. It is not to be confused with the Angolan, Namibian, and South African Namib coastal de ...
. In birds,
golden eagles The golden eagle (''Aquila chrysaetos'') is a bird of prey living in the Northern Hemisphere. It is the most widely distributed species of eagle. Like all eagles, it belongs to the family Accipitridae. They are one of the best-known birds of ...
(''Aquila chrysaetos'') have territories of ,
least flycatcher The least flycatcher (''Empidonax minimus'') (also called chebec, or chebecker, after the sound it makes) is a small insect-eating bird. It is the smallest ''Empidonax'' flycatcher in eastern North America. Taxonomy The closest relative to the ...
s' (''Empidonax minimus'') territories are about and
gulls Gulls, or colloquially seagulls, are seabirds of the family Laridae in the suborder Lari. They are most closely related to the terns and skimmers and only distantly related to auks, and even more distantly to waders. Until the 21st century, m ...
have territories of only a few square centimetres in the immediate vicinity of the nest. Territories can be linear.
Sanderling The sanderling (''Calidris alba'') is a small wading bird. The name derives from Old English ''sand-yrðling'', "sand-ploughman". The genus name is from Ancient Greek ''kalidris'' or ''skalidris'', a term used by Aristotle for some grey-colou ...
s (''Calidris alba'') forage on beaches and sandflats. When on beaches, they feed either in flocks or individual territories of 10 to 120 metres of shoreline. The time to develop territories varies between animals. The
marine iguana The marine iguana (''Amblyrhynchus cristatus''), also known as the sea iguana, saltwater iguana, or Galápagos marine iguana, is a species of iguana found only on the Galápagos Islands (Ecuador). Unique among modern lizards, it is a marine repti ...
(''Amblyrhynchus cristatus'') is a lekking reptile. Males start to establish small display territories two months ahead of the mating season.


Retaining a territory

Rather than retaining a territory simply by fighting, for some animals this can be a 3-stage process. Many animals create "sign-posts" to advertise their territory. Sometimes these sign-posts are on the boundary thereby demarcating the territory, or, may be scattered throughout the territory. These communicate to other animals that the territory is occupied and may also communicate additional information such as the sex, reproductive status or dominance status of the territory-holder. Sign-posts may communicate information by
olfactory The sense of smell, or olfaction, is the special sense through which smells (or odors) are perceived. The sense of smell has many functions, including detecting desirable foods, hazards, and pheromones, and plays a role in taste. In humans, it ...
, auditory, or visual means, or a combination of these. If an intruder progresses further into the territory beyond the sign-posts and encounters the territory-holder, both animals may begin
ritualized aggression Ritualized aggression is when animals use a range of behaviours as posture or warning but without engaging in actual aggression, which is expensive in terms of energy and the risk of injury. Ritualized aggression involves a graded series of behavi ...
toward each other. This is a series of stylised postures, vocalisations, displays, etc. which function to solve the territory dispute without actual fighting as this could injure either or both animals. Ritualized aggression often ends by one of the animals fleeing (generally the intruder). If this does not happen, the territory may be defended by actual fighting, although this is generally a last resort.


Advertising the territory


Scent marking

Scent marking, also known as territorial marking or spraying when this involves
urination Urination, also known as micturition, is the release of urine from the urinary bladder through the urethra to the outside of the body. It is the urinary system's form of excretion. It is also known medically as micturition, voiding, uresis, ...
, is a behaviour used by animals to identify their territory. Most commonly, this is accomplished by depositing strong-smelling substances contained in the
urine Urine is a liquid by-product of metabolism in humans and in many other animals. Urine flows from the kidneys through the ureters to the urinary bladder. Urination results in urine being excretion, excreted from the body through the urethra. Cel ...
,
faeces Feces ( or faeces), known colloquially and in slang as poo and poop, are the solid or semi-solid remains of food that was not digested in the small intestine, and has been broken down by bacteria in the large intestine. Feces contain a relati ...
, or, from specialised
scent gland Scent gland are exocrine glands found in most mammals. They produce semi-viscous secretions which contain pheromones and other semiochemical compounds. These odor-messengers indicate information such as status, territorial marking, mood, and sexu ...
s located on various areas of the body. Often, the scent contains
pheromones A pheromone () is a secreted or excreted chemical factor that triggers a social response in members of the same species. Pheromones are chemicals capable of acting like hormones outside the body of the secreting individual, to affect the behavio ...
or carrier proteins such as the
major urinary proteins Major urinary proteins (Mups), also known as α2u-globulins, are a subfamily of proteins found in abundance in the urine and other secretions of many animals. Mups provide a small range of identifying information about the donor animal, when dete ...
to stabilize the odours and maintain them for longer. The animal sniffing the scent frequently displays a
flehmen response The flehmen response (; from German ''flehmen'', to bare the upper teeth, and Upper Saxon German ''flemmen'', to look spiteful), also called the flehmen position, flehmen reaction, flehmen grimace, flehming, or flehmening, is a behavior in which ...
to assist in detecting the mark. Scent marking is often performed by
scent rubbing Scent rubbing is a behavior where a mammal rubs its body against an object in their environment, sometimes in ones covered with strongly odored substances. It is typically shown in carnivores, although many mammals exhibit this behavior. Lowering ...
in many mammals. In many mammal species, scent marking is more frequent during the
breeding season Seasonal breeders are animal species that successfully mate only during certain times of the year. These times of year allow for the optimization of survival of young due to factors such as ambient temperature, food and water availability, and cha ...
.
Felid Felidae () is the family of mammals in the order Carnivora colloquially referred to as cats, and constitutes a clade. A member of this family is also called a felid (). The term "cat" refers both to felids in general and specifically to the dom ...
s such as
leopard The leopard (''Panthera pardus'') is one of the five extant species in the genus '' Panthera'', a member of the cat family, Felidae. It occurs in a wide range in sub-Saharan Africa, in some parts of Western and Central Asia, Southern Russia, a ...
s and
jaguar The jaguar (''Panthera onca'') is a large cat species and the only living member of the genus '' Panthera'' native to the Americas. With a body length of up to and a weight of up to , it is the largest cat species in the Americas and the th ...
s mark by rubbing themselves against vegetation.
Prosimian Prosimians are a group of primates that includes all living and extinct Strepsirrhini, strepsirrhines (lemurs, Lorisoidea, lorisoids, and Adapiformes, adapiforms), as well as the Haplorhini, haplorhine tarsiers and their extinct relatives, the O ...
s and
New World monkey New World monkeys are the five families of primates that are found in the tropical regions of Mexico, Central and South America: Callitrichidae, Cebidae, Aotidae, Pitheciidae, and Atelidae. The five families are ranked together as the Ceboidea ( ...
s also use scent marking, including urine washing (
self-anointing Self-anointing in animals, sometimes called anointing or anting, is a behaviour whereby a non-human animal smears odoriferous substances over themselves. These substances are often the secretions, parts, or entire bodies of other animals or plant ...
the body with urine), to communicate. Many
ungulate Ungulates ( ) are members of the diverse clade Ungulata which primarily consists of large mammals with hooves. These include odd-toed ungulates such as horses, rhinoceroses, and tapirs; and even-toed ungulates such as cattle, pigs, giraffes, cam ...
s, for example the
blue wildebeest The blue wildebeest (''Connochaetes taurinus''), also called the common wildebeest, white-bearded gnu or brindled gnu, is a large antelope and one of the two species of wildebeest. It is placed in the genus '' Connochaetes'' and family Bovidae, a ...
, use scent marking from two glands, the
preorbital gland The preorbital gland is a paired exocrine gland found in many species of hoofed animals, which is homologous to the lacrimal gland found in humans. These glands are trenchlike slits of dark blue to black, nearly bare skin extending from the med ...
and a scent gland in the
hoof The hoof (plural: hooves) is the tip of a toe of an ungulate mammal, which is covered and strengthened with a thick and horny keratin covering. Artiodactyls are even-toed ungulates, species whose feet have an even number of digits, yet the rumin ...
. Territorial scent marking may involve behaviours specific to this activity. When a wolf marks its territory, it lifts a hind leg and urinates on a scent post (usually an elevated position like a tree, rock, or bush). This raised leg urination is different from normal urination, which is done while squatting. This posture is exclusive to alpha wolves of either sex, although the alpha male does this most often. The alpha female usually urinates on a scent post that her breeding partner has just urinated on, although during the mating season, the female may first urinate on the ground. All other females in the pack, and also young wolves and low-ranking male wolves, urinate while squatting. Males and female
ring-tailed lemur The ring-tailed lemur (''Lemur catta'') is a large strepsirrhine primate and the most recognized lemur due to its long, black and white ringed tail. It belongs to Lemuridae, one of five lemur families, and is the only member of the ''Lemur'' ge ...
s (''Lemur catta'') scent-mark both vertical and horizontal surfaces at the overlaps in their home ranges using their anogenital scent glands. To do this, they perform a handstand to mark vertical surfaces, grasping the highest point with their feet while applying the scent. In the Eastern carpenter bee, ''
Xylocopa virginica ''Xylocopa virginica'', sometimes referred to as the eastern carpenter bee, extends through the eastern United States and into Canada. They are Sympatry, sympatric with ''Xylocopa micans'' in much of southeastern United States. They nest in variou ...
'', both sexes have glands that evolved for marking the nest. Males, although they have the gland, are unable to produce the marking substance. Females secrete it near the nest site entrance to establish their territory.
Wombat Wombats are short-legged, muscular quadrupedal marsupials that are native to Australia. They are about in length with small, stubby tails and weigh between . All three of the extant species are members of the family Vombatidae. They are adap ...
s use feces to mark their territory. They have evolved specialized intestinal anatomy to produce cubical feces to ensure the feces do not roll away.


Visual

Visual sign-posts may be a short-term or long-term mode of advertising a territory. Short-term communication includes the colouration or behaviour of the animal, which can only be communicated when the resident is present. Other animals may use more long-term visual signals such as faecal deposits, or marks on the vegetation or ground. Visual marking of territory is often combined with other modes of animal communication. Some animals have prominent "badges" or visual displays to advertise their territory, often in combination with scent marking or auditory signals. Male
European robins The European robin (''Erithacus rubecula''), known simply as the robin or robin redbreast in Great Britain & Ireland, is a small insectivorous passerine bird that belongs to the chat subfamily of the Old World flycatcher family. About in le ...
are noted for their highly aggressive territorial behaviour. They attack other males that stray into their territories, and have been observed attacking other small birds without apparent provocation. Such attacks sometimes lead to fatalities, accounting for up to 10% of adult robin deaths in some areas. The red breast of the bird (i.e. badge) is highly visible when it sings (vocal marking) at the boundary of its territory. The ring-tailed lemur (''Lemur catta'') advertises its territory with urine scent marks. When it is urinating for marking purposes, it holds its extremely distinctive tail high in the air adding a visual component to the advertisement; when it is urinating for eliminative purposes, its tail is only slightly raised.
Rhinoceros A rhinoceros (; ; ), commonly abbreviated to rhino, is a member of any of the five extant species (or numerous extinct species) of odd-toed ungulates in the family Rhinocerotidae. (It can also refer to a member of any of the extinct species o ...
have poor vision but may use visual marking. Dominant
white rhino The white rhinoceros, white rhino or square-lipped rhinoceros (''Ceratotherium simum'') is the largest extant species of rhinoceros. It has a wide mouth used for grazing and is the most social of all rhino species. The white rhinoceros consists ...
bulls mark their territory with faeces and urine (olfactory marking). The dung is laid in well defined piles. There may be 20 to 30 of these piles to alert passing rhinoceroses that it is occupied territory. Other males may deposit dung over the piles of another and subsequently the sign-post grows larger and larger. Such a dung heap can become up to five metres wide and one metre high. After defecating, greater one-horned rhinos scratch their hind feet in the dung. By continuing to walk, they “transport” their own smell around the paths, thus establishing a scent-marked trail. Another method of visually marking their territory is wiping their horns on bushes or the ground and scraping with the feet, although this is likely combined with the smell of the marking animal. The territorial male scrape-marks every or so around its territory boundary. After leaving a urination mark, some animals scrape or dig the ground nearby, thereby leaving a visual advertisement of the territory. This includes domestic
dog The dog (''Canis familiaris'' or ''Canis lupus familiaris'') is a domesticated descendant of the wolf. Also called the domestic dog, it is derived from the extinct Pleistocene wolf, and the modern wolf is the dog's nearest living relative. Do ...
s. Several species scratch or chew trees leaving a visual mark of their territory. This is sometimes combined with rubbing on the tree which may leave tufts of fur. These include the
Canada lynx The Canada lynx (''Lynx canadensis''), or Canadian lynx, is a medium-sized North American lynx that ranges across Alaska, Canada, and northern areas of the contiguous United States. It is characterized by its long, dense fur, triangular ears ...
(''Lynx canadensis'') and the
American black bear The American black bear (''Ursus americanus''), also called simply a black bear or sometimes a baribal, is a medium-sized bear endemic to North America. It is the continent's smallest and most widely distributed bear species. American black bear ...
(''Ursus americanus''). Many animals have scent glands in their paws or deposit fur during tree-marking, so tree-marking may be a combination of both visual and olfactory advertising of the territory. The male ring-tailed lemur has a specialised adaptation to assist in leaving visual/olfactory territorial marks. On their inner forearm (antebrachial) is a scent gland which is covered by a
spur A spur is a metal tool designed to be worn in pairs on the heels of riding boots for the purpose of directing a horse or other animal to move forward or laterally while riding. It is usually used to refine the riding aids (commands) and to back ...
. In a behaviour called "spur marking", they grasp the substrate, usually a small sapling, and drag the spur over it, cutting into the wood and spreading the gland's secretions. When on the ground, ring-tailed lemurs preferentially mark small saplings and when high in the trees, they usually mark small vertical branches.
European wildcat The European wildcat (''Felis silvestris'') is a small wildcat species native to continental Europe, Scotland, Turkey and the Caucasus. It inhabits forests from the Iberian Peninsula, Italy, Central and Eastern Europe to the Caucasus. Its fur is ...
s (''Felis silvestris'') deposit their faecal marks on plants with high visual conspicuousness that enhances the visual effectiveness of the signal.


Auditory

Many animals use vocalisations to advertise their territory. These are short-term signals transmitted only when the animal is present, but can travel long distances and over varied habitats. Examples of animals which use auditory signals include birds, frogs and canids.
Wolves The wolf (''Canis lupus''; plural, : wolves), also known as the gray wolf or grey wolf, is a large Canis, canine native to Eurasia and North America. More than thirty subspecies of Canis lupus, subspecies of ''Canis lupus'' have been reco ...
advertise their territories to other packs through a combination of scent marking and howling. Under certain conditions, wolf howls can be heard over areas of up to . When howling together, wolves harmonize rather than chorus on the same note, thus creating the illusion of there being more wolves than there actually are. Wolves from different geographic locations may howl in different fashions: the howls of European wolves are much more protracted and melodious than those of North American wolves, whose howls are louder and have a stronger emphasis on the first syllable.


Ritualized aggression

Animals use a range of behaviours to intimidate intruders and defend their territories, but without engaging in fights which are expensive in terms of energy and the risk of injury. This is
ritualized aggression Ritualized aggression is when animals use a range of behaviours as posture or warning but without engaging in actual aggression, which is expensive in terms of energy and the risk of injury. Ritualized aggression involves a graded series of behavi ...
. Such defense frequently involves a graded series of behaviours or displays that include threatening gestures (such as vocalizations, spreading of wings or gill covers, lifting and presentation of claws, head bobbing, tail and body beating) and finally, direct attack.


Defense

Territories may be held by an individual, a
mated In biology, mating is the pairing of either opposite- sex or hermaphroditic organisms for the purposes of sexual reproduction. ''Fertilization'' is the fusion of two gametes. ''Copulation'' is the union of the sex organs of two sexually reprodu ...
or unmated pair, or a group. Territoriality is not always a fixed behavioural characteristic of a species. For example, red foxes (''Vulpes vulpes'') either establish stable home ranges within particular areas or are itinerant with
no fixed abode In law, no fixed abode or without fixed abode is not having a fixed geographical location as a residence, commonly referred to as no fixed address. This is applicable to several groups: * People who have a home, but which is not always in the ...
. Territories may vary with time (season), for example,
European robin The European robin (''Erithacus rubecula''), known simply as the robin or robin redbreast in Great Britain & Ireland, is a small insectivorous passerine bird that belongs to the chat subfamily of the Old World flycatcher family. About in len ...
s defend territories as pairs during the breeding season but as individuals during the winter. Resource availability may cause changes in territoriality, for example, some
nectarivore In zoology, a nectarivore is an animal which derives its energy and nutrient requirements from a diet consisting mainly or exclusively of the sugar-rich nectar produced by flowering plants. Nectar as a food source presents a number of benefits a ...
s defend territories only during the mornings when plants are richest in nectar. In species that do not form pair bonds, male and female territories are often independent, i.e. males defend territories only against other males and females only against other females. In this case, if the species is
polygynous Polygyny (; from Neoclassical Greek πολυγυνία (); ) is the most common and accepted form of polygamy around the world, entailing the marriage of a man with several women. Incidence Polygyny is more widespread in Africa than in any ...
, one male territory probably contains several female territories, while in some
polyandrous Polyandry (; ) is a form of polygamy in which a woman takes two or more husbands at the same time. Polyandry is contrasted with polygyny, involving one male and two or more females. If a marriage involves a plural number of "husbands and wives" ...
species such as the
northern jacana The northern jacana or northern jaçana (''Jacana spinosa'') is a wader which is known as a resident breeder from coastal Mexico to western Panama, and on Cuba, Jamaica and Hispaniola in the Caribbean. It sometimes known to breed in Texas, United ...
, this situation is reversed.


Strategies

Animals may use several strategies to defend their territories. The first game theory model of fighting is known as the ''
hawk-dove game The game of chicken, also known as the hawk–dove game or snowdrift game, is a model of conflict for two players in game theory. The principle of the game is that while the ideal outcome is for one player to yield (to avoid the worst outcome if ...
''. This model pits a hawk strategy (always try to injure your opponent and only withdraw from the contest if an injury is received) against a dove strategy (always use a non-injurious display if the rival is another dove and always withdraw if the rival is a hawk). Another strategy used in territory defence is the
war of attrition The War of Attrition ( ar, حرب الاستنزاف, Ḥarb al-Istinzāf; he, מלחמת ההתשה, Milhemet haHatashah) involved fighting between Israel and Egypt, Jordan, the Palestine Liberation Organisation (PLO) and their allies from ...
. In this model of aggression, two contestants compete for a resource by persisting while constantly accumulating costs over the time that the contest lasts. Strategically, the game is an auction in which the prize goes to the player with the highest bid, and each player pays the loser's low bid. Some animals use a strategy termed the ''
dear enemy effect The dear enemy effect or dear enemy recognition is an ethological phenomenon in which two neighbouring territorial animals become less aggressive toward one another once territorial borders are well established. As territory owners become accustome ...
'' in which two neighbouring territorial animals become less aggressive toward one another once territorial borders are well-established and they are familiar to each other, but aggression toward unfamiliar animals remains unaffected. The converse of this is the ''
nasty neighbour effect In ethology, the nasty neighbour effect describes the phenomenon whereby territory-holding animals behave more strongly toward familiar conspecific neighbours than to unfamiliar conspecifics. This phenomenon may be generally advantageous to an ani ...
'' in which a territory-holder shows heightened aggression toward neighbouring territory-holders but unaffected aggression to unfamiliar animals or distant territory-holders. These contrasting strategies depend on which intruder (familiar or unfamiliar) poses the greatest threat to the resident territory-holder. In territory defence by groups of animals, ''
reciprocal altruism In evolutionary biology, reciprocal altruism is a behaviour whereby an organism acts in a manner that temporarily reduces its fitness while increasing another organism's fitness, with the expectation that the other organism will act in a similar m ...
'' can operate whereby the cost to the benefactor in helping defend the territory is less than the gains to the beneficiary.


Resources defended

An animal chooses its territory by deciding what part of its home range it will defend. In selecting a territory, the size and quality play crucial roles in determining an animal's habitat. Territory size generally tends to be no larger than the organism requires to survive, because defending a larger territory incurs greater energy, time and risk of injury costs. For some animals, the territory size is not the most important aspect of territoriality, but rather the quality of the defended territory. Behavioural ecologists have argued that food distribution determines whether a species is territorial or not, however, this may be too narrow a perspective. Several other type of resource may be defended including partners, potential mates, offspring, nests or lairs, display areas or
leks A lek is an aggregation of male animals gathered to engage in competitive displays and courtship rituals, known as lekking, to entice visiting females which are surveying prospective partners with which to mate. A lek can also indicate an avail ...
. Territoriality emerges where there is a focused resource that provides enough for the individual or group, within a boundary that is small enough to be defended without the expenditure of excessive effort. Territoriality is often most strong towards
conspecifics Biological specificity is the tendency of a characteristic such as a behavior or a biochemical variation to occur in a particular species. Biochemist Linus Pauling stated that "Biological specificity is the set of characteristics of living organis ...
, as shown in the case of redlip blenny. This is because the conspecifics share exactly the same set of resources. Several types of resource in a territory may be defended. Food: Large solitary (or paired) carnivores, such as
bear Bears are carnivoran mammals of the family Ursidae. They are classified as caniforms, or doglike carnivorans. Although only eight species of bears are extant, they are widespread, appearing in a wide variety of habitats throughout the Nor ...
s and the bigger raptors require an extensive protected area to guarantee their food supply. This territoriality only breaks down when there is a glut of food, for example when
grizzly bear The grizzly bear (''Ursus arctos horribilis''), also known as the North American brown bear or simply grizzly, is a population or subspecies of the brown bear inhabiting North America. In addition to the mainland grizzly (''Ursus arctos horri ...
s are attracted to migrating
salmon Salmon () is the common name for several list of commercially important fish species, commercially important species of euryhaline ray-finned fish from the family (biology), family Salmonidae, which are native to tributary, tributaries of the ...
. Food related territoriality is least likely with insectivorous birds, where the food supply is plentiful but unpredictably distributed.
Swift Swift or SWIFT most commonly refers to: * SWIFT, an international organization facilitating transactions between banks ** SWIFT code * Swift (programming language) * Swift (bird), a family of birds It may also refer to: Organizations * SWIFT, ...
s rarely defend an area larger than the nest. Conversely, other insectivorous birds that occupy more constrained territories, such as the ground-nesting
blacksmith lapwing The blacksmith lapwing or blacksmith plover (''Vanellus armatus'') is a lapwing species that occurs commonly from Kenya through central Tanzania to southern and southwestern Africa. The vernacular name derives from the repeated metallic 'tink, ti ...
may be very territorial, especially in the breeding season during which they not only threaten or attack many kinds of intruders, but have stereotyped display behaviour to deter conspecifics sharing neighbouring nesting spots. The owl limpet (''Lottia gigantea'') is a large (up to 8 cm in length) limpet. It lives in association with an approximately 1,000 cm^2 area of algal film in which its grazing marks can be seen, whereas the remainder of the rock surface is usually free of any visible film. These areas of algal film represent the territories of the Lottia; within them the animals do all their grazing. They keep their territories free of other organisms by shoving off any intruders: other Lottia, grazing limpets of the genus Acmaea, predatory snails, and sessile organisms such as anemones and barnacles. Nests and offspring: Many birds, particularly seabirds, nest in dense communities but are nonetheless territorial in defending their nesting site to within the distance they can reach while brooding. This is necessary to prevent attacks on their own chicks or nesting material from neighbours. Commonly the resulting superimposition of the short-range repulsion onto the long-range attraction characteristically leads to the well-known roughly hexagonal spacing of nests. One gets a similar hexagonal spacing resulting from the territorial behaviour of gardening limpets such as species of
Scutellastra ''Scutellastra'' is a genus of sea snails with gills, typical true limpets, marine gastropod molluscs in the family Patellidae, the true limpets.Bouchet, P. (2012). Scutellastra H. Adams & A. Adams, 1854. Accessed through: World Register of ...
. They vigorously defend their gardens of particular species of algae, that extend for perhaps 1–2 cm around the periphery of their shells. The desert grass spider, ''
Agelenopsis aperta ''Agelenopsis aperta'', also known as the desert grass spider or funnel-web spider, is a species of spider belonging to the family Agelenidae and the genus ''Agelenopsis''. It is found in dry and arid regions across the southern United States a ...
,'' often engages in fights over its territory and the most combative spiders have the largest territories. Some species of penguin defend their nests from intruders trying to steal the pebbles from which the nest is constructed. Mating opportunities: The striped mouse (''
Rhabdomys ''Rhabdomys'' is a largely Southern African genus of muroid rodents slightly larger than house mice. They are known variously as striped or four-striped mice or rats. Traditionally the genus has been seen as a single species, ''Rhabdomys pumilio ...
pumilio'') is group living with one single breeding male and up to 4 communally breeding females per group. Groups typically contain several
philopatric Philopatry is the tendency of an organism to stay in or habitually return to a particular area. The causes of philopatry are numerous, but natal philopatry, where animals return to their birthplace to breed, may be the most common. The term derives ...
adult sons (and daughters) that are believed not to breed in their natal group and all group members participate in territorial defence. Males defend their territory using a nasty neignbour strategy. Group-living male breeders are nearly five times more aggressive towards their neighbours than towards strangers, leading to the prediction that neighbours are the most important competitors for paternity. Using a molecular parentage analysis it has been shown that 28% of offspring are sired by neighbouring males and only 7% by strangers. In certain species of butterflies, such as the
Australian painted lady The Australian painted lady (''Vanessa kershawi'') is a species of butterfly mostly confined to Australia, although westerly winds have dispersed it to islands east of Australia, including New Zealand. Debate surrounds the taxonomy of this spe ...
butterfly and the
speckled wood butterfly The speckled wood (''Pararge aegeria'') is a butterfly found in and on the borders of woodland areas throughout much of the Palearctic realm. The species is subdivided into multiple subspecies, including ''Pararge aegeria aegeria'', ''Pararge ae ...
, the male defends territories that receptive females are likely to fly through such as sunny hilltops and sunspots on a forest's floor. Territory defence in male variegated pupfish (''
Cyprinodon ''Cyprinodon'' is a genus of pupfishes found in waters that range from fresh to hypersaline. The genus is primarily found in Mexico, the Caribbean Islands and southern United States (Arizona, California, Florida, Nevada, New Mexico, Oklahoma and ...
variegatus'') is dependent on the presence of females. Reduced aggression consistent with the dear enemy effect occurs between conspecific neighbours in the absence of females, but the presence of a female in a male's territory instigates comparably greater aggression between the neighbours. In the
Skylark ''Alauda'' is a genus of larks found across much of Europe, Asia and in the mountains of north Africa, and one of the species (the Raso lark) endemic to the islet of Raso in the Cape Verde Islands. Further, at least two additional species are ...
(''Alauda arvensis''), playbacks of neighbour and stranger songs at three periods of the breeding season show that neighbours are dear enemies in the middle of the season, when territories are stable, but not at the beginning of the breeding season, during settlement and pair formation, nor at the end, when bird density increases due to the presence of young birds becoming independent. Thus, this dear enemy territoriality relationship is not a fixed pattern but a flexible one likely to evolve with social and ecological circumstances. Some species of bees also exhibit territoriality to defend mating sites. For example, in '' Euglossa imperialis,'' a non-social bee species, males have been observed to occasionally form aggregations of fragrance-rich territories, considered to be leks. These leks serve only a facultative purpose for this species, in which the more fragrance-rich sites there are, the greater the number of habitable territories. Since these territories are aggregated, females have a large selection of males with whom to potentially mate within the aggregation, giving females the power of
mate choice Mate choice is one of the primary mechanisms under which evolution can occur. It is characterized by a "selective response by animals to particular stimuli" which can be observed as behavior.Bateson, Paul Patrick Gordon. "Mate Choice." Mate Choic ...
. Similar behaviour is also observed in the ''
Eulaema meriana ''Eulaema meriana'' is a large-bodied bee species in the tribe Euglossini, otherwise known as the orchid bees. The species is a solitary bee and is native to tropical Central and South America. The male collects fragrances from orchid flowers, w ...
'' orchid bee. Males in this species of bee show alternative behaviours of territoriality and transiency. Transient male bees did not defend territories, but instead flew from one territory to the other. They also did not engage in physical contact with the territorial males. On the other hand, territorial males patrolled an area around a tree and used the same territory for up to 49 days. It also appeared that they gave up territories to new males without violence. Males defend territories solely for mating, and no other resources such as fragrances, nests, nest construction materials, nectar, or pollen are found at these territories.


Single resource territories

Although most territories contain multiple (potential) resources, some territories are defended for only one purpose. European blackbirds may defend feeding territories that are distant from their nest sites, and in some species that form leks, for example in the Uganda kob (a
grazing antelope A grazing antelope is any of the species of antelope that make up the subfamily Hippotraginae or tribe Hippotragini of the family Bovidae The Bovidae comprise the biological family of cloven-hoofed, ruminant mammals that includes cattle, bi ...
) and the marine iguana, males defend the lek site which is used only for mating.


Polyterritoriality

Many species demonstrate polyterritoriality, referring to the act of claiming or defending more than one territory. In the
European pied flycatcher The European pied flycatcher (''Ficedula hypoleuca'') is a small passerine bird in the Old World flycatcher family. One of the four species of Western Palearctic black-and-white flycatchers, it bird hybrid, hybridizes to a limited extent with th ...
(''Ficedula hypoleuca''), researchers assert that males exhibit polyterritoriality to deceive females of the species into entering into polygynous relationships. This hypothesis, named the
deception Deception or falsehood is an act or statement that misleads, hides the truth, or promotes a belief, concept, or idea that is not true. It is often done for personal gain or advantage. Deception can involve dissimulation, propaganda and sleight o ...
hypothesis, claims that males have territories at distances sufficiently great that females are unable to discern already-mated males. The observation that males travelled long distances, ranging from 200m to 3.5 km, to find a second mate supports this argument. The debate about polyterritoriality in this species may initiate research about the evolution and reasons for polyterritoriality in other unrelated species.


See also

*
Aggression Aggression is overt or covert, often harmful, social interaction with the intention of inflicting damage or other harm upon another individual; although it can be channeled into creative and practical outlets for some. It may occur either reacti ...
*
Alpha (biology) In biology, a dominance hierarchy (formerly and colloquially called a pecking order) is a type of social hierarchy that arises when members of animal social groups interact, creating a ranking system. A dominant higher-ranking individual is som ...
*
Biological interaction In ecology, a biological interaction is the effect that a pair of organisms living together in a community have on each other. They can be either of the same species (intraspecific interactions), or of different species (interspecific interaction ...
*
Border control Border control refers to measures taken by governments to monitor and regulate the movement of people, animals, and goods across land, air, and maritime borders. While border control is typically associated with international borders, it a ...
*
Dear enemy recognition The dear enemy effect or dear enemy recognition is an ethological phenomenon in which two neighbouring territorial animals become less aggressive toward one another once territorial borders are well established. As territory owners become accustom ...
*
Home range A home range is the area in which an animal lives and moves on a periodic basis. It is related to the concept of an animal's territory which is the area that is actively defended. The concept of a home range was introduced by W. H. Burt in 1943. He ...
*
Property Property is a system of rights that gives people legal control of valuable things, and also refers to the valuable things themselves. Depending on the nature of the property, an owner of property may have the right to consume, alter, share, r ...
* ''
The Territorial Imperative ''The Territorial Imperative: A Personal Inquiry Into the Animal Origins of Property and Nations'' is a 1966 nonfiction book by American writer Robert Ardrey. It describes the evolutionarily determined instinct among humans toward territoriality ...
''


References


Further reading

* Walther, F. R., E. C. Mungall, G. A. Grau. (1983) ''Gazelles and their relatives : a study in territorial behavior'' Park Ridge, N.J. : Noyes Publications 239, * Stokes, A. W. (editor) (1974) ''Territory'' Stroudsburg, Pa., Dowden, Hutchinson & Ross 398, * Klopfer, P. H. (1969) ''Habitats and territories; a study of the use of space by animals'' New York, Basic Books 117 p.


External links

{{DEFAULTSORT:Territory Ethology Biological interactions
Territorial A territory is an area of land, sea, or space, particularly belonging or connected to a country, person, or animal. In international politics, a territory is usually either the total area from which a state may extract power resources or a ...