Showing papers on "Territoriality published in 1990"

The ecology of territoriality in small mammals

Abstract: Recent research on space use and social behavior of small mammals has revealed pronounced differences in the degree of territoriality between species and between sexes within species. Hypotheses to explain these differences have been based on optimality approaches. Leading hypotheses are that the spatial distribution, abundance and renewal rates of food resources determine whether females defend territories, and that the spatial and temporal pattern of availability of females determines whether males are territorial. Other hypotheses invoke resources other than food, or maintain that territoriality in females deters infanticide. This review briefly summarizes these hypotheses and evaluates recently collected evidence from comparative and experimental studies.

An Experimental Comparison of Male and Female Spawning Territoriality in a Pacific Salmon

Abstract: The spawning territoriality of male and female non-anadromous sockeye salmon, Oncorhynchus nerka, was examined experimentally by comparing the resources sought after, the behaviours used in intrasexual competition, and the correlates of success in intrasexual competition for each sex. Females expressed territorial behaviour both in the presence and absence of males, defending specific, repeatedly selected, spawning sites. In contrast, males exhibited clear territorial behaviour only in the presence of females, defending access to specific females and positions over time. Size was a factor in determining which females established territories within preferred areas, but this advantage was largely negated by prior residency. Size was a major factor in determining which males gained closest access to individual females, with smaller males adopting subordinate, sneak, positions. Prior residence was also a significant factor in determining the outcome of contests for access to females, with the weight of this factor dependent on the relative sizes of competing males. The behavioural differences between sexes appear to arise from differences both in the resources defended and the relative costs of potential losses for each sex.

Demography of agile gibbons (Hylobates agilis)

Abstract: Demographic processes and the structure of a population of agile gibbons (Hylobates agilis) were investigated over 6 years in the Gunung Palung Reserve, Indonesia. Estimates of population size, density, and biomass revealed a population whose groups were stable in size and composition. Demographic processes place gibbons at risk, however, to short-term changes in their environment. Patterns of survival, fecundity, mortality, and dispersal combined to produce negative rates of growth. In addition, a top-heavy age-class distribution, with adults forming a large fraction of animals, makes it unlikely that this population could recover rapidly from a decline in numbers. Two behavioral factors, territoriality and monogamy, account for the size and stability of gibbon groups. Monogamy imposes limits on group size, while mating patterns and territoriality decrease the impact of sources of high mortality common in other primate species. These relationships underscore the fundamental importance of behavioral influence on demographic processes and social structure.

Non-resource based territoriality in males of the butterfly Xamia xami (Lepidoptera: Lycaenidae)

Abstract: In the Pedregal de San Angel reserve, in Mexico City, males of the butterfly Xamia xamiperch in and defend areas with well-defined topographic limits. These areas lack concentrations of receptive females and of larvae and adult resources. One individual defends the same territory an average of 5 h/day, up to a maximum of 23 days. The same areas are used as territories by different males during the year. These areas share some characteristic features which are described. Evidence is presented in support of the hypothesis that the territories function as mating stations. A possible scenario for the evolution of this territorial mating system is advanced.

Phenotypic Flexibility in the Social Organization of Clethrionomys

Abstract: I review the flexibility of social organization and spacing behavior in Clethrionomys. This review is based on a 6-year comparative study and several experimental studies on cyclic populations of the bank vole, C. glareolus, in Central Finland. The social organization of Clethrionomys populations shows great flexibility during both the breeding and nonbreeding season, and is dependent on habitat patchiness, food availability, Predation, kinship, philopatry, and familiarity between individuals. The first three factors are most important in destabilizing a population, whereas the last three stabilize a population without exhausting its resources. Female territoriality can weaken in a productive environment perhaps due to increasing kinship between reproductive females during the breeding season. During the winter, food availability seems to determine the social structure of the population, which consists of either large or small aggregations of both sexes. Winter territoriality may be influenced by relatively homogenous habitat with low productivity. Forest-dwelling species of Clethrionomys seem to adopt behavioral tactics different from those of most Microtus that live in a productive, but unstable habitat. Despite these behavioral differences, both genera cycle synchronously in northern Fennoscandia. This leads to the conclusion that we have to seek explanations for microtine cycles not based on the behavior of individual voles.

Oviposition resources, territoriality and male reproductive tactics in the dragonfly paltothemis lineatipes (odonata: libellulidae)

Abstract: Etude, chez Paltothemis lineatipes, des effets de l'addition de ressources d'oviposition a des territoires de mâles sur le comportement reproducteur des femelles et les tactiques adoptees par les mâles

Territoriality and threat perceptions in urban humans

Abstract: Most investigators intuitively view territory and territoriality as two different sides of the same conceptual coin. Territory is seen as implying some measurable spatial entity, i.e., area, distance or volume; while territoriality is used to refer to a behavioural propensity of individuals or groups to monopolize a territory by excluding others from it (Altum, 1868; Howard, 1920; Mayr, 1935; Nobel, 1939; also see review in Malmberg, 1983). Thus defined, territoriality is a form of aggression (Wilson, 1975a) which, by default, has to be acted out or at least advertised for a territory to exist. An area that is not defended is not, strictly speaking, a territory and an animal which defends no area cannot, according to this view, be called territorial.

Home Color as a Territorial Marker

Abstract: Summary.-Effect of color of a neighboring home on house color was investigated in a smd town in northern Minnesota. It was found that color matches across common boundaries were less frequent than expected based on a random distribution of house colors. This indicates that in selecting the color for a home, there is systematic avoidance of colors previously chosen by neighbors. This effect was specific to chromatic (nonwhite) houses, suggesting that color per se serves as a territorial marker. The territoriality of humans is a well-established phenomenon, although its relationship to territoriality in nonhuman vertebrates remains controversial. A territory may be defined as a defended space, and it is clear that humans defend a variety of territories in different ways (1, 2). Territories which are established in public areas (e.g., libraries, parks, beaches) have been the subject of many empirical studies but territorial behavior is just as evident at home. Family members engage in a rather rigid partition of available space in rooms, closets, beds, and at tables (5). Occupancy of common areas, such as bathrooms, may be defended by particular individuals for restricted time (1). Externally, a home may be marked by fences, nameplates, and other signs of proprietorship. Frequency of such markers is correlated with behavioral indicators of territorial defense such as latency to answer the doorbell (4). Territorial markers also appear to prevent crimes against property (2). Although modifications of external features of a home (furnishings, artworks, decoration) have been identified as territorial markers (2), color of the home has never been systematically examined as a transmitter of information about territorial occupancy.