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Author Boyce, P.N.; McLoughlin, P.D. url  doi
openurl 
  Title Ecological Interactions Involving Feral Horses and Predators: Review with Implications for Biodiversity Conservation Type Journal Article
  Year 2021 Publication The Journal of Wildlife Management Abbreviated Journal Jour. Wild. Mgmt.  
  Volume n/a Issue n/a Pages  
  Keywords apparent competition; artificial selection; community ecology; conservation; feral horse (Equus ferus caballus); life history; predator-prey dynamics  
  Abstract ABSTRACT For many ecosystems, feral horses are increasingly becoming an important if not dominant component of ungulate biomass and hence influence on community dynamics. Yet we still know little of how horses contribute to key ecological interactions including predator-prey and indirect competitive relationships at a community level. Notably, feral species like horses can exhibit life-history traits that differ from that of native (mainly artiodactyl) herbivore competitors. Artificial selection for traits like increased, early, or extended reproduction that have yet to be reversed by natural selection, coupled with naturally selected differences in anatomy and behavior, in addition to unique management objectives for horses compared to other species, means that the dynamics of feral horse populations are not likely to align with what might be expected of other large herbivores. Unexpected population dynamics and inherent biological asymmetries between native ungulates and feral horses may therefore influence the former via direct competition for shared resources and through enemy-mediated interactions like apparent competition. In several localities feral horses now co-exist with multiple native prey species, some of which are in decline or are species at risk. Compounding risks to native species from direct or indirect competitive exclusion by horses is the unique nature and socio-political context of feral horse management, which tends towards allowing horse populations to be limited largely by natural, density-dependent factors. We summarize the inherent asymmetries between feral horse biology and that of other ungulate prey species with consequences for conservation, focusing on predator-prey and emerging indirect interactions in multi-prey systems, and highlight future directions to address key knowledge gaps in our understanding of how feral horses may now be contributing to the (re)structuring of food webs. Observations of patterns of rapid growth and decline, and associated skews in sex ratios of feral horse populations, indicate a heightened potential for indirect interactions among large ungulate prey species, where there is a prevalence of feral horses as preferred prey, particularly where native prey are declining. In places like western North America, we expect predator-prey interactions involving feral horses to become an increasingly important factor in the conservation of wildlife. This applies not only to economically or culturally important game species but also at-risk species, both predators (e.g., wolves [Canis lupus], grizzly bears [Ursus arctos]) and prey (e.g., woodland caribou [Rangifer tarandus caribou]), necessitating an ecological understanding of the role of horses in natural environments that goes beyond that of population control. ? 2021 The Wildlife Society.  
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  Publisher John Wiley & Sons, Ltd Place of Publication Editor  
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  ISSN 0022-541x ISBN Medium  
  Area Expedition Conference  
  Notes https://doi.org/10.1002/jwmg.21995 Approved no  
  Call Number Equine Behaviour @ team @ Serial 6642  
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Author Trillmich, F.; Rehling, A. url  doi
isbn  openurl
  Title Animal Communication: Parent-Offspring Type Book Chapter
  Year 2006 Publication Encyclopedia of Language & Linguistics Abbreviated Journal  
  Volume Issue Pages 284-288  
  Keywords Begging Strategies; Communication; Competition; Feeding Strategies; Fitness; Parental Care; Parent-Offspring Conflict; Recognition; Sibling Conflict  
  Abstract Parent-offspring communication has evolved under strong selection to guarantee that the valuable resource of parental care is expended efficiently on raising offspring. To ensure allocation of parental care to their own offspring, individual recognition becomes established in higher vertebrates when the young become mobile at a time when a nest site can no longer provide a safe cue to recognition. Such recognition needs to be established by rapid, sometimes imprinting-like, processes in animals producing precocial offspring. In parents, offering strategies that stimulate feeding and entice offspring to approach the right site have evolved. Such parental signals can be olfactory, acoustic, or visual. In offspring, begging strategies involve shuffling for the best place to obtain food – be this the most productive teat or the best position in the nest. This involves signals that make the offspring particularly obvious to the parent. Parents often feed young according to their signaling intensity but may also show favoritism for weaker offspring. Offspring signals also serve to communicate the continuing presence of the young and may thereby maintain brood-care behavior in parents. Internal processes in parents may end parental care irrespective of further signaling by offspring, thus ensuring that offspring cannot manipulate parents into providing substantially more care than is optimal for their own fitness.  
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  Publisher Elsevier Place of Publication Oxford Editor Keith Brown  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
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  ISSN ISBN 9780080448541 Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Equine Behaviour @ team @ Serial 4642  
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Author Smith, J.E.; Kolowski, J.M.; Graham, K.E.; Dawes, S.E.; Holekamp, K.E. url  doi
openurl 
  Title Social and ecological determinants of fission-fusion dynamics in the spotted hyaena Type Journal Article
  Year 2008 Publication Animal Behaviour. Abbreviated Journal Anim. Behav.  
  Volume 76 Issue 3 Pages 619-636  
  Keywords competition; conflict resolution; cooperative hunting; Crocuta crocuta; ecological constraints; group living; social rank  
  Abstract Theory predicts that individuals living in fission-fusion societies, in which group members frequently change subgroups, should modify grouping patterns in response to varying social and environmental conditions. Spotted hyaenas, Crocuta crocuta, are long-lived carnivores that reside in permanent social groups called clans. Clans are complex, fission-fusion societies in which individual members travel, rest and forage in subgroups that frequently change composition. We studied two clans in Kenya to provide the first detailed description of fission-fusion dynamics in this species. Because social and ecological circumstances can influence the cohesiveness of animal societies, we evaluated the extent to which specific circumstances promote the formation of subgroups of various sizes. We found that cooperative defence of shared resources during interclan competition and protection from lions were cohesive forces that promoted formation of large subgroups. We also tested hypotheses suggesting factors limiting subgroup size. Mothers with small cubs avoided conspecifics, thereby reducing infanticide risk. Victims of aggression either reconciled fights or separated from former opponents to reduce the immediate costs of escalated aggression in the absence of food. As predicted by the ecological constraints hypothesis, hyaenas adjusted their grouping patterns over both short and long time scales in response to feeding competition. Crocuta were most gregarious during periods of abundant prey, joined clanmates at ephemeral kills in numbers that correlated with the energetic value of the prey and gained the most energy when foraging alone because cooperative hunting attracted numerous competitors. Overall, our findings indicate that resource limitation constrains grouping in this species.  
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  Call Number Equine Behaviour @ team @ Serial 4676  
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Author Wittemyer, G.; Getz, W.M. url  doi
openurl 
  Title Hierarchical dominance structure and social organization in African elephants, Loxodonta africana Type Journal Article
  Year 2007 Publication Animal Behaviour. Abbreviated Journal Anim. Behav.  
  Volume 73 Issue 4 Pages 671-681  
  Keywords African elephant; between-group competition; Loxodonta africana; nepotism; resource distribution; socioecology; transitive dominance; within-group competition  
  Abstract According to the socioecological framework, transitivity (or linearity) in dominance relationships is related to competition over critical resources. When a population is structured into groups, the intensity of between- versus within-group competition influences the form and function of its social organization. Few studies have compared the type and relative intensity of competition at these two levels. African elephants have well-structured social relations, providing an exemplary system for such a study. We report on dominance hierarchies among free-ranging elephants and evaluate the factors that drive their socioecological structure to lie in a region of the three-dimensional nepotism/despotism/tolerance space rarely observed among social species; namely, where non-nepotistic, transitive dominance hierarchies within groups emerge despite kin-based philopatry and infrequent agonistic interactions over widely distributed resources. We found significant transitivity in dominance hierarchies between groups. Dominance relations among the matriarchs of different social groups were primarily age based, rather than driven by physical or group size, and group matriarch rank influenced the dominance relationships among nonmatriarchal females in the population. Our results suggest that between-group dominance relationships induce tolerance among group members, which in combination with high group relatedness, reduces the benefits of nepotism. We postulate that cognitive abilities and high risk of injury in contests enhance winner and loser effects, facilitating the formation of transitive dominance relationships, despite widely distributed resources over which infrequent competition occurs. The interplay of cognitive abilities, winner and loser effects, resource distribution, and within- and between-group dominance relationships may produce behaviour in other strongly social mammals that differs from that predicted by a superficial application of current socioecological models.  
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  Notes Approved no  
  Call Number refbase @ user @ Serial 449  
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Author Scordato, E.S.; Drea, C.M. url  doi
openurl 
  Title Scents and sensibility: information content of olfactory signals in the ringtailed lemur, Lemur catta Type Journal Article
  Year 2007 Publication Animal Behaviour. Abbreviated Journal Anim. Behav.  
  Volume 73 Issue 2 Pages 301-314  
  Keywords chemical communication; female dominance; individual recognition; intrasexual competition; Lemur catta; mate choice; reproductive signalling; ringtailed lemur; scent marking; seasonality  
  Abstract The function of olfactory signalling in social species is less well understood than in asocial species. Consequently, we examined olfactory communication in the ringtailed lemur, a socially complex primate that retains a functional vomeronasal organ, has well-developed scent glands and shows a suite of scent-marking behaviour. To assess the information content of different types of scent gland secretions, we decoupled olfactory cues from the visual and behavioural modalities with which scent marking is normally associated. We presented male and female subjects (signal receivers) with a series of choice tests between odours derived from conspecific donors (signal senders) varying by sex, age, social status and reproductive condition. We additionally examined the influence of the receivers' reproductive state and familiarity with the signaller. The reproductive condition, social status and familiarity of senders and receivers affected signal transmission; specifically, male receivers attended most to the odours of conspecifics in breeding condition and to the odours of familiar, dominant animals. By contrast, females varied their responses according to both their own reproductive state and that of the sender. Based on male and female patterns of countermarking, we suggest that scent marking serves a function in intergroup spacing and intrasexual competition for both sexes, as might be expected in a female-dominant species. By contrast, minimal female interest in male odours counters a female mate choice function for scent marking in this species. Nevertheless, scent marks are critical to male-male competition and, therefore, may be subject to sexual selection.  
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  Call Number Equine Behaviour @ team @ Serial 4648  
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Author Val-Laillet, D.; Passille, A.M. de; Rushen, J.; von Keyserlingk, M.A.G. url  doi
openurl 
  Title The concept of social dominance and the social distribution of feeding-related displacements between cows Type Journal Article
  Year 2008 Publication Applied Animal Behaviour Science Abbreviated Journal Appl. Anim. Behav. Sci.  
  Volume 111 Issue 1-2 Pages 158-172  
  Keywords Cattle; Social dominance; Competitive success; Hierarchy; Feeding competition  
  Abstract The aim of this study was to determine the extent to which the classical properties of social dominance describe the pattern of feeder-related displacements with groups of cattle. We also compared the advantages and disadvantages of three dominance indices for describing the competitive success at the feeder. We observed displacements at the feeder within six groups of 12 lactating dairy cows over 72 h per group. We demonstrated that the cattle in our experiment established a quasi-linear hierarchy at the feeder where many dominance relationships were bi-directional (52.0 +/- 5.9%); namely, dominance relationships were significantly linear (P < 0.05 in five of the six groups) but contained many circular triads (45.0 +/- 5.6%). Dominance rank influenced the milk production (r = 0.36, P = 0.002) and the time budget of the animals: high-ranking cows were found spending more time at the feeder during the 120 min following provision of fresh food than low-ranking cows (P = 0.022), but dominance indices based on the occurrence of displacements at the feeder did not correlate with actual time spent at the feeder. The presence of numerous circular triads and bi-directional relationships suggests that the classical properties of social dominance do not correspond to the pattern of displacements that occur at feeders within small groups of cattle. Instead, the competitive success may also be affected by motivation or persistence by the animal to gain access to the food resource.  
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  Notes Approved no  
  Call Number Equine Behaviour @ team @ Serial 4213  
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Author Thoren Hellsten, E.; Viklund, A.; Koenen, E.P.C.; Ricard, A.; Bruns, E.; Philipsson, J. url  doi
openurl 
  Title Review of genetic parameters estimated at stallion and young horse performance tests and their correlations with later results in dressage and show-jumping competition Type Journal Article
  Year 2006 Publication Livestock Science Abbreviated Journal  
  Volume 103 Issue 1-2 Pages 1-12  
  Keywords Genetic parameters; Sport horse; Performance test; Competition; Dressage; Show-jumping  
  Abstract Results from performance tests and competitions of young horses are used by major European warmblood horse breeding associations for genetic evaluations. The aim of this review was to compare genetic parameters for various tests of young horses to assess their efficiency in selection for dressage and show-jumping. Improved understanding of genetic information across countries is also necessary, as foreign trade with semen is rapidly increasing. The review is based on inquiries to European breed associations and on (17) scientific publications available, which have analysed genetic parameters of young horse data and/or relationships between young and mature horse results in sport. Despite differences in testing methods of young horses, results for major horse populations were in good agreement. Specially designed young horse performance tests, including stallion tests, showed high heritabilities and high genetic correlations with later competition results. We recommend that test results are encouraged to be used across countries for genetic evaluation of imported stallions and semen. Short station tests are generally preferred when selecting stallions for both dressage and jumping traits, whereas competition data may be used when selecting for only one discipline. We also recommend that extensive field testing of young horses is encouraged and should include both genders.  
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  Notes Approved no  
  Call Number refbase @ user @ Serial 3951  
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Author Huizinga, H.A.; Boukamp, M.; Smolders, G. url  openurl
  Title Estimated parameters of field performance testing of mares from the Dutch Warmblood riding horse population Type Journal Article
  Year 1990 Publication Livestock Production Science Abbreviated Journal  
  Volume 26 Issue 4 Pages 291-299  
  Keywords competition; genetic parameters; horse breeding; mares; performance test  
  Abstract The field performance testing (FPT) of mares of the Dutch Warmblood riding horse population is evaluated. Phenotypic and genetic parameters of scored traits are estimated and the genetic relationship with performance of half-sibs in dressage and jumping competition are estimated. Data from 1984 to 1987 are used, covering scores from 2023 at least 3-year-old mares. Seven subjectively scored traits are considered, walk, trot, canter, riding ability, character, jumping ability and total score. Analysis of data is according to a sire model. Variance and covariance components are estimated by Restricted Maximum Likelihood (REML) procedures. Estimates of heritability are moderately low for gaits (average 0.19), jumping ability (0.15) and total score (0.17) and extremely low for riding ability (0.03) and character (0.06). Dressage in competition is most correlated with riding ability (0.83) and is moderately correlated with total score (0.41) from FPT of mares. Jumping competition is most correlated with jumping ability (0.48) and not correlated with total score (0.05) from field test of mares. Some possible bias owing to previous knowledge and preselection is discussed. It is concluded that efficiency of present FPT of mares is limited for selection of broodmares for dressage and jumping ability in competition.  
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  Notes Approved no  
  Call Number refbase @ user @ Serial 3964  
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Author Wallin, L.; Strandberg, E.; Philipsson, J. url  openurl
  Title Genetic correlations between field test results of Swedish Warmblood Riding Horses as 4-year-olds and lifetime performance results in dressage and show jumping Type Journal Article
  Year 2003 Publication Livestock Production Science Abbreviated Journal  
  Volume 82 Issue 1 Pages 61-71  
  Keywords Horse; Performance test; Competition results; Animal model; Heritability; Genetic correlation  
  Abstract The main objective of this study was to estimate genetic correlations between traits of young sport horses (4 years old) evaluated in the Swedish Riding Horse Quality Test (RHQT) and later competition results in dressage and show jumping. The data comprised 3708 Warmblood horses born between 1968 and 1982 that had participated in the RHQT as 4-year-olds and 25[punctuation space]605 horses born between 1953 and 1995 with competition records. According to the criteria between 1206 and 1879 horses were common to this two files and were available for the estimations of the genetic correlations. Competition performance traits were cumulative points and cumulative placings received during a horse's lifetime, and a log10 transformation was used to achieve a more normal distribution of the data. Genetic correlations between gait traits scored in the RHQT and competition results in dressage were favourable, in the range 0.63-0.75, and between jumping traits scored in the RHQT and results in show jumping 0.83-0.93. Estimated heritabilities for gait and jumping traits scored in the RHQT were in the range 0.09-0.27 and 0.10-0.18, respectively. Estimated heritabilities for the cumulative points and cumulative placings in dressage and show jumping were 0.17/0.16 and 0.23/0.27, respectively. Thus, the results from the RHQT have proved to be useful for early genetic evaluation and selection of both mares and stallions for sport performance traits.  
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  Notes Approved no  
  Call Number refbase @ user @ Serial 3956  
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Author Kaminski, J.; Pitsch, A.; Tomasello, M. url  doi
openurl 
  Title Dogs steal in the dark Type Journal Article
  Year 2013 Publication Abbreviated Journal Animal Cognition  
  Volume 16 Issue 3 Pages 385-394  
  Keywords Domestic dog; Social cognition; Perspective taking; Competition  
  Abstract All current evidence of visual perspective taking in dogs can possibly be explained by dogs reacting to certain stimuli rather than understanding what others see. In the current study, we set up a situation in which contextual information and social cues are in conflict. A human always forbade the dog from taking a piece of food. The part of the room being illuminated was then varied, for example, either the area where the human was seated or the area where the food was located was lit. Results show that dogs steal significantly more food when it is dark compared to when it is light. While stealing forbidden food the dog’s behaviour also depends on the type of illumination in the room. Illumination around the food, but not the human, affected the dogs’ behaviour. This indicates that dogs do not take the sight of the human as a signal to avoid the food. It also cannot be explained by a low-level associative rule of avoiding illuminated food which dogs actually approach faster when they are in private. The current finding therefore raises the possibility that dogs take into account the human’s visual access to the food while making their decision to steal it.  
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  Publisher Springer-Verlag Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1435-9448 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Equine Behaviour @ team @ Serial 5669  
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