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| Author | Ben-Shahar, R | ||||
| Title | Selectivity in large generalist herbivores: feeding patterns of African ungulates in a semi-arid habitat | Type | Journal Article | ||
| Year | 1991 | Publication | African Journal of Ecology | Abbreviated Journal | Afr. J. Ecol. |
| Volume | 29 | Issue | 4 | Pages | 302-315 |
Keywords  |
diet; forage production; grazing; wildebeest; zebra | ||||
| Abstract | Feeding habits of free-ranging wildebeest and zebra were monitored in a semi-arid nature reserve, bordering the southwestern part of Kruger National Park, South Africa. The purpose of study was to distinguish and define the feeding niches of two roughage grazers that occur in similar habitat types. The monthly compositions of diets were evaluated by direct observations of feeding bouts over a period of two years when rainfall patterns were average and animal populations were stable. Other analyses evaluated the standing biomass of grass species in the reserve during the wet summer and dry winter seasons. A considerable overlap of grass species composition was found in the diets of wildebeest and zebra. Ordination of bi-monthly records of the diet composition showed greater variations in scores of grasses in zebra diet in comparison to wildebeest. Seasonal patterns were more apparent in the wildebeest diet. Preference ranking of grass species indicated that zebra diet remained constant in winter and summer. Wildebeest diet however, alternated with seasons, showing high preferences during the winter months for grass species which were rejected during summer. The combined assessment of results from three separate statistical methods analysing temporal patterns and preferences in diet composition revealed contradictory trends. The solution, however, relied on the initial assumptions posed. Hence, wildebeest and zebra are essentially generalist feeders which show a limited amount of preference in their choice of diet. |
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| Notes | Approved | no | |||
| Call Number | Equine Behaviour @ team @ | Serial | 2226 | ||
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| Author | Matsumura, S.; Kobayashi, T. | ||||
| Title | A game model for dominance relations among group-living animals | Type | Journal Article | ||
| Year | 1998 | Publication | Behavioral Ecology and Sociobiology | Abbreviated Journal | Behav. Ecol. Sociobiol. |
| Volume | 42 | Issue | 2 | Pages | 77-84 |
| Keywords |
Dominance – Hawk-dove games – Resource-holding potential – Asymmetry – Evolutionarily stable strategy | ||||
| Abstract | Abstract We present here an attempt to understand behaviors of dominant individuals and of subordinate individuals as behavior strategies in an asymmetric “hawk-dove” game. We assume that contestants have perfect information about relative fighting ability and the value of the resource. Any type of asymmetry, both relevant to and irrelevant to the fighting ability, can be considered. It is concluded that evolutionarily stable strategies (ESSs) depend on the resource value (V), the cost of injury (D), and the probability that the individual in one role will win (x). Different ESSs can exist even when values of V, D, and x are the same. The characteristics of dominance relations detected by observers may result from the ESSs that the individuals are adopting. The model explains some characteristics of dominance relations, for example, the consistent outcome of contests, the rare occurrence of escalated fights, and the discrepancy between resource holding potential (RHP) and dominance relations, from the viewpoint of individual selection. | ||||
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| Notes | Approved | no | |||
| Call Number | Equine Behaviour @ team @ | Serial | 5102 | ||
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| Author | Creel, S. | ||||
| Title | Social dominance and stress hormones | Type | Journal Article | ||
| Year | 2001 | Publication | Trends in Ecology & Evolution | Abbreviated Journal | Trends. Ecol. Evol |
| Volume | 16 | Issue | 9 | Pages | 491-497 |
| Keywords |
Dominance; rank; stress; glucocorticoids; cooperative breeding; sociality; behavioural endocrinology; mammals | ||||
| Abstract | In most cooperatively breeding birds and mammals, reproductive rates are lower for social subordinates than for dominants, and it is common for reproduction in subordinates to be completely suppressed. Early research conducted in captivity showed that losing fights can increase glucocorticoid (GC) secretion, a general response to stress. Because GCs can suppress reproduction, it has been widely argued that chronic stress might underlie reproductive suppression of social subordinates in cooperative breeders. Contradicting this hypothesis, recent studies of cooperative breeders in the wild show that dominant individuals have elevated GCs more often than do subordinates. The findings that elevated GCs can be a consequence of subordination or a cost of dominance complicate the conventional view of social stress, with broad ramifications for the evolution of dominance and reproductive suppression. | ||||
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| Notes | Approved | no | |||
| Call Number | Equine Behaviour @ team @ | Serial | 4072 | ||
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| Author | Sterck, E.; Watts, D.; van Schaik, C. | ||||
| Title | The evolution of female social relationships in nonhuman primates | Type | Journal Article | ||
| Year | 1997 | Publication | Behavioral Ecology and Sociobiology | Abbreviated Journal | Behav. Ecol. Sociobiol. |
| Volume | 41 | Issue | 5 | Pages | 291-309 |
| Keywords |
ecology; matrilocal; primate; social; theory | ||||
| Abstract | Considerable interspeci®c variation in female social relationships occurs in gregarious primates, particularly with regard to agonism and cooperation between females and to the quality of female relationships with males. This variation exists alongside variation in female philopatry and dispersal. Socioecological theories have tried to explain variation in female-female social relationships from an evolutionary perspective focused on ecological factors, notably predation and food distribution. According to the current ``ecological model'', predation risk forces females of most diurnal primate species to live in groups; the strength of the contest component of competition for resources within and between groups then largely determines social relationships between females. Social elationships among gregarious females are here characterized as DispersalEgalitarian, Resident-Nepotistic, Resident-Nepotistic-Tolerant, or Resident-Egalitarian. This ecological model has successfully explained i€erences in the occurrence of formal submission signals, decided dominance relation ships, coalitions and female philopatry. Group size and female rank generally a€ect female reproduction success as the model predicts, and studies of closely related species in di€erent ecological circumstances underscore the importance of the model. Some cases, however, can only be explained when we extend the model to incorporate the e€ects of infanticide risk and habitat saturation. We review evidence in support of the ecological model and test the power of alternative models that invoke between-group competition, forced female philopatry, demographic female recruitment, male interventions into female aggression, and male harassment. Not one of these models can replace the ecological model, which already encompasses the between-group competition. Currently the best model, which explains several phenomena that the ecological model does not, is a ``socioecological model'' based on the combined importance of ecological factors, habitat saturation and infanticide avoidance. We note some points of similarity and divergence with other mammalian taxa; these remain to be explored in detail. |
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| Notes | Approved | no | |||
| Call Number | Equine Behaviour @ team @ | Serial | 5227 | ||
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| Author | Shrader, A.M.; Kerley, G.I.H.; Kotler, B.P.; Brown, J.S. | ||||
| Title | Social information, social feding, and competition in group-living goats (Capra hircus) | Type | Journal Article | ||
| Year | 2007 | Publication | Behavioral Ecology | Abbreviated Journal | Behav. Ecol. |
| Volume | 18 | Issue | 1 | Pages | 103-107 |
| Keywords |
fear, group foraging, harvest rates, intraspecific competition, social information. | ||||
| Abstract | There are both benefits (e.g., social information) and costs (e.g., intraspecific competition) for individuals foraging in groups. To ascertain how group-foraging goats (Capra hircus) deal with these trade-offs, we asked 1) do goats use social information to make foraging decisions and 2) how do they adjust their intake rate in light of having attracted by other group members? To establish whether goats use social information, we recorded their initial choice of different quality food patches when they were ignorant of patch quality and when they could observe others foraging. After determining that goats use social information, we recorded intake rates while they fed alone and in the presence of potential competitors. Intake rate increased as the number of competitors increased. Interestingly, lone goats achieved an intake rate that was higher than when one competitor was present but similar to when two or more competitors were present. Faster intake rates may allow herbivores to ingest a larger portion of the available food before competing group members arrive at the patch. This however, does not explain the high intake rates achieved when the goats were alone. We provide 2 potential explanations: 1) faster intake rates are a response to greater risk incurred by lone individuals, the loss of social information, and the fear of being left behind by the group and 2) when foraging alone, intake rate is no longer a trade-off between reducing competition and acquiring social information. Thus, individuals are able to feed close to their maximum rate. | ||||
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| Notes | 10.1093/beheco/arl057 | Approved | no | ||
| Call Number | refbase @ user @ | Serial | 814 | ||
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| Author | Dugatkin, L.; Alfieri, M. | ||||
| Title | Tit-For-Tat in guppies (Poecilia reticulata): the relative nature of cooperation and defection during predator inspection | Type | Journal Article | ||
| Year | 1991 | Publication | Evolutionary Ecology | Abbreviated Journal | Evol. Ecol. |
| Volume | 5 | Issue | 3 | Pages | 300-309 |
| Keywords |
Game theory – Tit-For-Tat – predator inspection – guppy | ||||
| Abstract | Summary The introduction of game-theoretical thinking into evolutionary biology has laid the groundwork for a heuristic view of animal behaviour in which individuals employ “strategies” – rules that instruct them how to behave in a given circumstance to maximize relative fitness. Axelrod and Hamilton (1981) found that a strategy called Tit-For-Tat (TFT) is one robust cooperative solution to the iterated Prisoner's Dilemma game. There exists, however, little empirical evidence that animals employ TFT. Predator inspection in fish provides one ecological context in which to examine the use of the TFT strategy. | ||||
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| Notes | Approved | no | |||
| Call Number | Equine Behaviour @ team @ | Serial | 2177 | ||
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| Author | Czaran, T. | ||||
| Title | Game theory and evolutionary ecology: Evolutionary Games & Population Dynamics by J. Hofbauer and K. Sigmund, and Game Theory & Animal Behaviour, edited by L.A. Dugatkin and H.K. Reeve | Type | Journal Article | ||
| Year | 1999 | Publication | Trends in Ecology & Evolution | Abbreviated Journal | Trends. Ecol. Evol |
| Volume | 14 | Issue | 6 | Pages | 246-247 |
| Keywords |
Game theory; Evolutionary ecology; Population dynamics; Ethology | ||||
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| Notes | Approved | no | |||
| Call Number | refbase @ user @ | Serial | 485 | ||
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| Author | Ronnenberg, K.; Habbe, B.; Gräber, R.; Strauß, E.; Siebert, U. | ||||
| Title | Coexistence of wolves and humans in a densely populated region (Lower Saxony, Germany) | Type | Journal Article | ||
| Year | 2017 | Publication | Basic and Applied Ecology | Abbreviated Journal | Basic. Appl. Ecol. |
| Volume | 25 | Issue | Pages | 1-14 | |
| Keywords |
Grey wolf; ; Habitat use; Species distribution models; Predator-prey interactions | ||||
| Abstract | Since the first sporadic occurrences of grey wolves (Canis lupus) west of the Polish border in 1996, wolves have shown a rapid population recovery in Germany. Wolves are known to avoid people and wolf attacks on humans are very rare worldwide. However, the subjectively perceived threat is considerable, especially as food-conditioned habituation to humans occurs sporadically. Lower Saxony (Germany) has an exceedingly higher human population density than most other regions with territorial wolves; thus, the potential for human-wolf conflicts is higher. Using hunters' wildlife survey data from 455 municipalities and two years (2014-2015) and data from the official wolf monitoring (557 confirmed wolf presences and 500 background points) collected between 2012-2015, grey wolf habitat selection was modelled using generalized additive models with respect to human population density, road density, forest cover and roe deer density. Moreover, we tested whether habitat use changed in response to human population and road density between 2012/2013 and 2014/2015. Wolves showed a preference for areas of low road density. Human population density was less important as a covariate in the model of the survey data. Areas with higher prey abundance (5-10 roe deer/km2) and areas with >20% forest cover were preferred wolf habitats. Wolves were mostly restricted to areas with the lowest road and human population densities. However, between the two time periods, avoidance of human density decreased significantly. Recolonization of Germany is still in its early stages and it is unclear where this process will halt. To-date authorities mainly concentrate on monitoring measures. However, to avoid conflict, recolonization will require more stringent management of wolf populations and an improved information strategy for rural populations. | ||||
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| ISSN | 1439-1791 | ISBN | Medium | ||
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| Notes | Approved | no | |||
| Call Number | Equine Behaviour @ team @ | Serial | 6397 | ||
| Permanent link to this record | |||||
| Author | Taberlet, P.; Waits, L.P.; Luikart, G. | ||||
| Title | Noninvasive genetic sampling: look before you leap | Type | Journal Article | ||
| Year | 1999 | Publication | Trends in Ecology & Evolution | Abbreviated Journal | Trends Ecol. Evol |
| Volume | 14 | Issue | 8 | Pages | 323-327 |
| Keywords |
Hairs; Feces; Feathers; Allelic dropout; Individual identification; Conservation genetics; Behavioural ecology; Pilot study; Microsatellites; Probability of identity | ||||
| Abstract | Noninvasive sampling allows genetic studies of free-ranging animals without the need to capture or even observe them, and thus allows questions to be addressed that cannot be answered using conventional methods. Initially, this sampling strategy promised to exploit fully the existing DNA-based technology for studies in ethology, conservation biology and population genetics. However, recent work now indicates the need for a more cautious approach, which includes quantifying the genotyping error rate. Despite this, many of the difficulties of noninvasive sampling will probably be overcome with improved methodology. | ||||
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| ISSN | 0169-5347 | ISBN | Medium | ||
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| Notes | Approved | no | |||
| Call Number | Equine Behaviour @ team @ | Serial | 6573 | ||
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| Author | Barton, R.A.; Byrne, R.W.; Whiten, A. | ||||
| Title | Ecology, feeding competition and social structure in baboons | Type | Journal Article | ||
| Year | 1996 | Publication | Behavioral Ecology and Sociobiology | Abbreviated Journal | Behav. Ecol. Sociobiol. |
| Volume | 38 | Issue | 5 | Pages | 321-329 |
| Keywords |
Key words Ecology – Competition – Group size – Baboons | ||||
| Abstract | Predictions of the model of van Schaik (1989) of female-bonding in primates are tested by systematically comparing the ecology, level of within-group contest competition for food (WGC), and patterns of social behaviour found in two contrasting baboon populations. Significant differences were found in food distribution (percentage of the diet from clumped sources), feeding supplant rates and grooming patterns. In accord with the model, the tendencies of females to affiliate and form coalitions with one another, and to be philopatric, were strongest where ecological conditions promoted WGC. Group fission in the population with strong WGC was “horizontal” with respect to female dominance rank, and associated with female-female aggression during a period of elevated feeding competition. In contrast, where WGC was low, females' grooming was focused on adult males rather than other females. Recent evidence suggests that group fission here is initiated by males, tends to result in the formation of one-male groups, and is not related to feeding competition but to male-male competition for mates. An ecological model of baboon social structure is presented which incorporates the effects of female-female competition, male-male competition, and predation pressure. The model potentially accounts for wide variability in group size, group structure and social relationships within the genus Papio. Socio-ecological convergence between common baboons and hamadryas baboons, however, may be limited in some respects by phylogenetic inertia. | ||||
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| Notes | Approved | no | |||
| Call Number | refbase @ user @ | Serial | 807 | ||
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