In this study, I investigate the adaptive significance and consequences of territorial behavior in buffleheads (Bucephala albeola) . The aims are: (1) to test the hypotheses that territorial males defend the food supply, the female or the nest site, (2) to test the hypothesis that brooding females defend the food supply, and (3) to examine whether territorial behavior or nest site availability limits breeding density. 1) Males defend a territory from the pre-laying stage until late incubation. The size of male territories was not related to food abundance, and food was poorly correlated with reproductive success. When the males of seven laying females were removed, four widowed females were evicted from their territory by neighboring males; widowed females also spent less time feeding and more time alert. Females tended to settle on a territory adjacent to their nest, and those that did not do so suffered a higher rate of nest parasitism. I suggest that protection of the female is a major function of male territories and that protection of the nest site is a secondary function. 2) Females become territorial after hatching the brood but they defend a different territory. The size of the brood territory was inversely correlated with food density and the relationship was hyperbolic. Growth rate and survival of ducklings was negatively correlated with brood density in one year and survival was positively correlated with food density in another year. I suggest that brood territories secure an adequate food supply for the young and that females adjust territory size according to both food and brood densities. 3) Natural nest sites were not in short supply and the addition of nest boxes did not increase breeding density. Breeding density was stable over the four years of this study. When I removed seven territorial males, four were replaced. I propose a model to explain the variability of territorial behavior in ducks. This model is based on the hypothesis that mate-guarding is a major function of territorial behavior, and predicts that the degree of territoriality is correlated with habitat variability. A review of the territorial status of 69 species of ducks is consistent with the model. I conclude that breeding buffleheads exhibit two kinds of territorial behavior: males are territorial during the nesting season to protect the female and provide her with an undisturbed feeding area (i.e. mate-guarding), and also to protect the nest site; females are territorial during the brood-rearing stage to secure food resources. Territorial behavior of nesting pairs further appears to limit breeding density. / Science, Faculty of / Zoology, Department of / Graduate

Thesis (M.S.)--University of Michigan, 1980.

Thesis (M.S.)--University of Michigan, 1980.

The effects of food abundance on the population dynamics and territorial behaviour of red squirrels were examined during a four year study in south-central British Columbia, Canada. I used a short-term, ad libitum addition of supplemental food in Douglas fir (low squirrel population density) and white spruce (high squirrel population density) forest habitats to examine changes in demography and spacing behaviour. Removal experiments in spring and autumn assessed the effect of residents on breeding density and juvenile recruitment and the influence of settlement patterns on recolonization density. If food is a limiting resource, I expected population density, recruitment, body weight, growth rates and reproduction to increase on the food supplemented areas. Population density in spruce control habitat was consistently twice as high as in Douglas fir control habitat (26 vs. 15) from 1985 to 1988. The addition of supplemental food resulted in a four-fold increase in population density in Douglas fir habitat and a two-fold increase in spruce habitat, indicating that populations in both habitats were food limited, but more strongly in Douglas fir habitat. The increase in density was the result of a strong increase in the recruitment of immigrants, primarily juveniles of unknown origin. Both recruitment to the food-supplemented grids and the decline in density following the removal of food were density-dependent. Stable population density may be the result of an inflexible territory size despite large changes in food abundance. To test this hypothesis, I monitored changes in territory size, home range size, the number of territories, intruder pressure, movement patterns and activity budgets in response to supplemental food. Supplemental food significantly decreased territory size and resulted in a five-fold increase in the number of territories in Douglas fir habitat. Territory size did not decrease in white spruce habitat, but there was a two-fold increase in the number of territories. In both habitats, immigrants established territories in previously unoccupied areas and in Douglas fir habitat, some immigrants established small territories on areas formerly used by residents who had defended large territories. There was an increase in the intensity that red squirrels travelled over their territories, a decrease in the proportion of time spent away from their territories and an increase in the proportion of time spent defending their territories. These behavioural changes appeared to offset the increased competitor density on the enriched territories, enabling red squirrels to defend territories larger than necessary for their current food requirements. This limited flexibility in territory size may reduce the amplitude of fluctuations in population density despite large changes in food abundance. Territorial behaviour can limit breeding density and juvenile recruitment. When territorial residents were removed from Douglas fir habitat in spring, red squirrel populations returned to a density similar to the control or pre-removal density in five of six removal trials. In autumn, population density returned to control or pre-removal densities in four of six trials. In white spruce habitat, population density returned to control or pre-removal levels in three of four trials in both spring and autumn. In both Douglas fir and spruce habitat, immigrants of unknown origin repopulated the removal areas. After removals in spring, females in breeding condition immigrated to the removal areas in five of six trials in Douglas fir habitat and in all four trials in spruce habitat. Settlement patterns did not appear to influence either territory size or recolonization density. / Science, Faculty of / Zoology, Department of / Graduate

No description available.

This is an inquiry into human personal space at a basic descriptive level. Its purpose is to observe some of the characteristics of personal space configurations as measured by a projective technique and to see how certain conditions may effect them.

The threespot damselfish, Stegastes planifrons, maintains individual territories that are clustered on coral patch reefs. My objective was to understand the effects of territory clustering on behavior and fitness. Fish with territories in the center of a cluster had (relative to edge fish): higher mating success (number of eggs), higher aggressive chase rates with conspecifics, lower chase rates to heterospecifics, lower overall chase rates, lower grazing rates by intruders, and smaller territories. Feeding rate, survivorship, and age at maturity did not vary with territory position. Therefore, central fish appeared to have higher fitness, which was probably related to the lower energetic costs of territory defense there. Center and edge territories differed in habitat complexity, and the density of potential algal competitors, egg predators, and various food and invertebrate species. These microhabitat features could provide different quality shelter, nest or feeding sites and thus might explain the positional differences in fitness. An experiment in which I changed the position of treatment fish from the center to the edge of a cluster, without altering microhabitat, showed that position per Se, and not microhabitat variation, caused the center-edge differences. Vacated space in the center of a cluster was fought over more vigorously and reoccuppied sooner than similar space on the edge. Settlement to one of two depopulated clusters was preferentially to the cluster center. These data indicated that threespots compete for the more desirable central positions. Therefore, these populations can be considered simultaneously recruitment limited (in terms of local population size) and resource limited (in terms of local reproductive output and perhaps global population size). Aggressive chases with conspecifics were lower on the cluster edge than at any distance toward the center, while chases to heterospecifics had the opposite pattern. The results of chases with conspecifics did not fit the predictions of the model by Stamps et al. (1987) . This discrepancy may be a result of habituation between territorial neighbors. / Graduation date: 1995

Little is known about the costs of relocating a territory into an established neighbourhood. In this study we investigated short-term costs of relocation in the longfin damselfish, Stegastes diencaeus, on a fringing reef in Barbados. Experimental removals of residents created vacancies, and focal observations over two days examined the intensity and duration of behavioural changes in the newcomers. Newcomers used smaller territories than original residents, and exhibited increased movement, increased agonistic behaviour and decreased foraging. The behavioural changes suggest that energetics are a major cost to relocation, but that opportunity costs, predation risk and injuries are also important. Differences between strangers and expanding neighbours support the concept of 'dear enemy' recognition, but familiarity does not influence the agonistic behaviour initiated by these newcomers. The costs reported here represent important limitations to the mobility of individuals and provide insights into the stability of fish territories.

Analysing the processes and relationships of political territoriality and collective identity in the American borderlands, this thesis examines the narrative and material dimensions of policies increasingly favouring securitised border 'control'. This 'reterritorialisation' contrasts markedly with concurrent moves to increase economic integration under the North American Free Trade Agreement and with long patterns of transnational socio-cultural interaction, emblematic of larger relational, transnational 'mobilities' fostered by globalisation. Through a historical and transdisciplinary survey, borders are examined as representations and socio-political constructs: a unique, contingent, political cartography connected to a precise, early modern notion of space and identity. Borders are in a continual process of being reproduced through both material means and supportive state-produced 'texts' or narratives. The analysis is part of a larger project in International Relations: the development of the 'identities/borders/orders' heuristic triad, designed to narrow and produce new theoretical and empirical insights by coupling three key concepts and exploring the co-constitutive relationships. Focussing on the identity-border link within the triad, the first case study analyses 'Operation Hold the Line' and related events in the securitisation of the southern borderlands against undocumented migration. The second case study provides an account of major official documentation and public debate framing current developments on the northern border, including a reading of the Illegal Immigration Reform and Immigrant Responsibility Act of 1996. Border policy is understood as an example of reflexive territoriality, suggesting continual, ever speedier revision, monitoring, and reproduction of a state's constructed strategy responding to control defined 'risks', such as migration. These regulations are fed and actualised by new information flows and technologies, as the state's attempt to 'control' its borders by making them political realities of difference with particular material and normative outcomes. Here, the politics of representation involves an image of border 'security' which effects the socio-spatialisation of collective identity, specifically the reinforcement of difference and a secure nationalism narrative. The securitisation also reflects a modern understanding of knowledge as regulation and order.

This thesis proposes a new method of dividing a task between members of a robot team. This method is dynamic territoriality. Territoriality is an emergent method of distributing resources between animals- each animal independently marks and defends their own area. Territoriality has previously been used on robot teams with varying results; these robot territorial systems did little or no adaptation to the environment or task, unlike natural territorial systems. / A dynamic territorial system adapts the territories to fit the environment, and the task the robot team must perform. The algorithm used to generate the territories is a novel extension of the ant clustering algorithm. Given a topological map of the space, it divides a space into a pre-specified number of territories such that the territories have minimal contact and near-equal area. The dynamic territorial algorithm was tested using hand-generated topological maps, then on physical environments. A robot system was developed to traverse an area and generate a topological map usable by the algorithm. / Dynamic territoriality can be used by simple robot teams to organize tasks such as multi- robot cleaning, monitoring and surveillance. The territories divide a complex environment into several simpler environments; this makes many tasks easier to perform. As the dynamic territorial algorithm is designed to minimize connections between territories, robot surveillance teams can capture or track intruders most easily at the territorial boundaries. Predator-prey and robot simulations were used to demonstrate the effectiveness of this territorial system in multi-robot surveillance. / This thesis extends previous work in territorial robotics and biologically inspired algorithms to create a new multi-robot control system. This control system has been implemented in hardware using a new topological mapping system. The thesis shows that this new multi-robot control system can effectively survey an area. In particular, it can control the movement of large groups of targets, or targets that move faster than the robots. / Thesis (PhD)--University of South Australia, 2005.