|   | 
Details
   web
Records
Author Zeitler-Feicht, M. H.; Streit, S.; Dempfle, L.
Title Automatic feeding systems for horses in group housing systems with regard to animal welfare. Part 2: Comparison of different automatic feeding systems Type Journal Article
Year 2011 Publication Tierärztliche Praxis Großtiere Abbreviated Journal Tierärztl Prax
Volume 39 Issue G Pages 33-40
Keywords Pferd, Fütterungssystem, Bauvarianten, soziale Interaktionen, Besuchshäufigkeit, Aufenthaltsdauer, Herzfrequenz, Verletzungsrisiko [Horse, feeding system, different types of construction, social interactions, visiting frequency, duration of stay, heart rate, risk of injury]
Abstract (down) Ziel: Überprüfung der Tiergerechtheit von in der Bauweise unterschiedlichen

Futterabrufstationen für Pferde in Gruppenhaltung anhand ethologischer

und physiologischer Parameter. Material und Methoden: In 32

Offenlaufställen (452 Pferde) mit computergesteuerten Abrufstationen

für Kraftfutter und Heu erfolgten kontinuierliche Direktbeobachtungen

für je einen 24-Stunden-Tag (Tortenstückverfahren). Erfasst wurden: Aufenthaltsdauer,

Besuchshäufigkeit, Droh- und Meideverhalten im Fütterungsbereich,

Blockaden sowie Herzfrequenz und Integumentverletzungen.

Ergebnisse: Eine Durchlaufstation reduzierte die Zahl der Auseinandersetzungen

im Fütterungsbereich signifikant. Ansonsten erhöhten die

für das fressende Pferd tiergerechten Varianten (Fressstand mit Eingangssperre,

ohne Austreibehilfe) Besuchshäufigkeit und Aufenthaltsdauer und

steigerten somit auch die Anzahl an Drohgesten je Tier und Tag. Insgesamt

betrachtet kann jedoch die Anzahl an sozionegativen Interaktionen

im Fütterungsbereich der Abrufstationen als relativ gering eingestuft

werden. Die Herzfrequenz lag im Warteareal bei den meisten Pferden im

physiologischen Bereich (45,1 ± 12,42 Schläge/min), erhöhte sich jedoch

in der Abrufstation um ca. 20 Schläge/min. Einige Tiere zeigten möglicherweise

stressbedingt kurzfristig auffallend hohe Werte (≥ 100 Schläge/

min). Integumentverletzungen im Zusammenhang mit dem Fütterungssystem

traten nicht auf. Der wichtigste Einflussfaktor auf die Untersuchungskriterien

war der Betrieb (Fläche, Konzeption, Management).

Schlussfolgerung: Durchlaufstationen sind pferdegerechter als Rücklaufstationen.

Nicht tiergerecht sind Stationen mit stromführender Austreibehilfe.

Weitere bauliche Unterschiede der derzeitigen Futterabrufstationen

dürften eher von untergeordneter Bedeutung sein, vor allem da

Flächengebot und Konzeption der Offenstallanlage sowie das Management

die überprüften Kriterien zur Tiergerechtheit maßgeblich beeinflussen.

Untersuchungen zur Abklärung der Ursache für die vereinzelt aufgetretenen

sehr hohen Herzfrequenzwerte sollten durchgeführt werden.

Objective: Comparison with regard to animal welfare of different automatic

feeding systems for hay and concentrate in group housing systems

for horses using parameters of ethology and physiology. Material and

methods: Parameters of research comprised: duration of stay, frequency

of visit, threatening behaviour with and without risk of injury, and avoiding

behaviour as well as heart rate and injuries of the integument. 452

horses were observed at the feeding area of 32 run-out-sheds. Every group

of horses was continuously observed following the pie chart system for

24 hours. Results: The “walk-through” station significantly reduced the

number of conflicts in the feeding area, whereas those systems which are

appropriate for the feeding horses (feeding station with access barrier and

without stimulation device by electric shock) led to a higher frequency of

visits and a longer duration of stay resulting in more threatening gestures.

However, the number of negative interactions in the feeding area of the

feeding systems can all together be classified as relatively insignificant.

The heart rate was within the physiological range (45.1 ± 12.42 beats/min)

in the waiting area, but increased by approximately 20 beats/min on average

within the feeding station. Some horses showed a very high heart rate

(≥ 100 beats/min) while entering the feeding station, possibly stress-related.

There were no injuries of the integument associated with the feeding

systems. The most important factor of the observation criteria was the

individual group housing system with its different dimensions, conception

and management. Conclusion: “Walk-through” stations are better than

”walk-back” stations with regard to animal welfare. Likewise, automatic

feeding stations with a current-carrying stimulation device are not supportive

of good welfare. The other differences between the constructions

of feeding stations of present systems are probably of less importance, particularly

as it was shown that the stable (management, stable area, conception)

had a significant influence on the surveyed parameters. Investigations

to obtain information on the cause for the sporadic occurrence of

very high heart rate values should be undertaken.]
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Equine Behaviour @ team @ Serial 5766
Permanent link to this record
 

 
Author Murray, J.K.; Singer, E.R.; Morgan, K.L.; Proudman, C.J.; French, N.P.
Title Memory decay and performance-related information bias in the reporting of scores by event riders Type Journal Article
Year 2004 Publication Preventive Veterinary Medicine Abbreviated Journal
Volume 63 Issue 3-4 Pages 173-182
Keywords Reporting bias; Memory decay; Risk factors; Horse; Cross-country
Abstract (down) We used data from a case-control study investigating risk factors for horse falls in the cross-country phase of eventing in Great Britain (GB) to examine evidence for memory decay and information bias. Responses to two questions obtained by telephone for 173 cases and 521 controls were examined for evidence of differential reporting according to the respondent's case-control status and performance in the dressage and cross-country phases of competitions. Information bias was found in the accuracy of reporting dressage penalty scores when analysed as a function of performance level (good/poor). Poor dressage performers were less likely to report accurate dressage scores than good performers. The accuracy of reporting dressage scores decreased as the time between the event and questionnaire completion increased, with no case-control interaction. Competitors who incurred cross-country jumping penalties at the event preceding the selected event reported their cross-country scores with less accuracy when compared with competitors who incurred no penalties. No information bias was found when the reporting of dressage and cross-country scores were analysed as a function of respondent category (case/control).
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number refbase @ user @ Serial 3955
Permanent link to this record
 

 
Author Flauger, B.; Krueger, K.
Title Aggressionslevel und Platzangebot bei Pferden (Equus caballus) [ Aggression level and enclosure size in horses (Equus caballus)] Type Journal Article
Year 2013 Publication Pferdeheilkunde Abbreviated Journal
Volume 29 Issue 4 Pages 495-504
Keywords Aggression / Verletzungsgefahr / Sozialverhalten / Gruppenhaltung / Pferdehaltung / Eingliederung von Pferden [aggression / injury risk / social behaviour / group housing / horse management / introduction of horses]
Abstract (down) Viele Pferdebesitzer bevorzugen aus Angst vor aggressiven Interaktionen und Verletzungsgefahr der Tiere untereinander die Einzelhaltung, obwohl von Tierschutzorganisationen die Gruppenhaltung für Pferde empfohlen wird. In dieser Studie beobachteten wir während des alltäglichen Soziallebens als auch bei der Eingliederung von neuen Gruppenmitgliedern das Sozialverhalten, insbesondere das Aggressionsverhalten, von elf Gruppen domestizierter Pferde (Equus caballus) verschiedener Größe und Zusammensetzung. Während des alltäglichen Soziallebens hatten die Gruppe und der Paddock-Typ (Gras / kein Gras) keinen Einfluss auf die Verhaltensweisen, wohingegen die Paddockgröße unter 10000 m2 einen signifikanten Einfluss auf die submissiven Verhaltensweisen (GzLM; n=56; t=-2.061, P=0.044) und einen nicht signifikanten Einfluss auf die aggressiven Verhaltensweisen (GzLM; n=56; t=-1.782, P=0.081) hatte. Allerdings verringerten sich sowohl die aggressiven als auch die submissiven Verhaltensweisen mit steigendem Platzangebot bis zu 10000 m2 (Spearman rank Korrelation; n=56; aggressive Verhaltensweisen: r = -0.313, P = 0.019; submissive Verhaltensweisen: r = -0.328, P = 0.014). Während den Eingliederungen reduzierten sich die Aggressionen pro Stunde mit der Vergrößerung des Platzangebotes (Spearman rank Korrelation; n=28; r=-0.402, P=0.034). Dies zeigte sich noch deutlicher, wenn Beobachtungen mit einem Platzangebot von über 10000 m2 ausgeschlos- sen wurden (Spearman rank Korrelation; n=23; r=-0.549, P=0.007). Während des alltäglichen Soziallebens näherte sich der Aggressionslevel der Nulllinie an, wenn das Platzangebot pro Pferd mehr als 331 m2 betrug. Deshalb empfehlen wir zur Reduzierung des Aggressionslevels und des Verletzungsrisikos von sozial gehaltenen Pferdegruppen ein Platzangebot von mindestens 331 m2 pro Pferd.

[Even though animal welfare organisations propose group housing for horse welfare, many owners stable horses individually for fear of aggressive interactions and injury risks. In the present study we observed social behaviour, and especially aggressiveness, in eleven domestic horse groups (Equus caballus) of different size and composition, in basic social situations and when new group members were introduced. During basic social situations, the group and the type of paddock (grass / no grass) had no effect on any of the behaviours, where- as the enclosure size below 10,000 m2 had a significant effect on submissive behaviour (GzLM; n=56; t=-2.061, P=0.044) and an insignificant effect on aggressive behaviour (GzLM; n=56; t=-1.782, P=0.081). However, aggressive and submissive behaviour dimi- nished with the increase of enclosure sizes up to 10,000 m2 (Spearman rank correlation; n = 56; aggressive behaviour: r = -0.313, P=0.019; submissive behaviour: r=-0.328, P=0.014). During introductions, aggression levels per hour decreased with any increase of enclosure size (Spearman rank correlation; n=28; r=-0.402, P=0.034) and even more when enclosure sizes above 10,000 m2 were excluded (Spearman rank correlation; n=23; r=-0.549, P=0.007). During basic social situations the aggression level approached zero when the space allowance was more than 331 m2 per horse. We therefore recommend keeping horse groups in an enclosure with at least 331 m2 per horse to reduce aggression and injuries.]
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Equine Behaviour @ team @ Serial 5714
Permanent link to this record
 

 
Author Peltzer, K.; Mabilu, M.G.; Mathoho, S.F.; Nekhwevha, A.P.; Sikhwivhilu, T.; Sinthumule, T.S.
Title Trauma history and severity of gambling involvement among horse-race gamblers in a South African gambling setting Type Journal Article
Year 2006 Publication Psychological Reports Abbreviated Journal Psychol Rep
Volume 99 Issue 2 Pages 472-476
Keywords Adult; African Continental Ancestry Group/*psychology/statistics & numerical data; Aged; Aged, 80 and over; Cross-Sectional Studies; Female; Gambling/*psychology; Humans; *Life Change Events; Male; Middle Aged; Personality Inventory; Risk Factors; *Social Environment; Socioeconomic Factors; South Africa; Statistics; Stress Disorders, Post-Traumatic/epidemiology/*psychology
Abstract (down) The purpose of this study was to ascertain the frequency of gambling involvement and the prevalence of problem gambling among horse race gamblers and to discover whether problem gambling in this sample is associated with a history of trauma. Among a sample of 266 South African horse-race gamblers (94% men and 6% women, Mage 46.8 yr., SD = 13.9, range 18-85 years), 31.2% were classified as probable pathological gamblers and 19.9% with problem gambling. Major weekly gambling activities included racetrack betting (82%), purchase of lottery tickets or scratch tickets (35%), purchase of sports lottery tickets (23%), and using casino type games (18%). Trauma history was significantly associated with gambling severity.
Address Human Sciences Research Council, University of Limpopo, Pretoria, South Africa. KPeltzer@hsrc.ac.za
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0033-2941 ISBN Medium
Area Expedition Conference
Notes PMID:17153816 Approved no
Call Number Serial 1850
Permanent link to this record
 

 
Author Candura, S.M.; Verni, P.; Minelli, C.M.; Rosso, G.L.; Cappelli, M.I.; Strambi, S.; Martellosio, V.
Title [Occupational risks among public safety and security forces] Type Journal Article
Year 2006 Publication Giornale Italiano di Medicina del Lavoro ed Ergonomia Abbreviated Journal G Ital Med Lav Ergon
Volume 28 Issue 1 Pages 53-62
Keywords Burnout, Professional/etiology; Climate; Health Education; Humans; *Law Enforcement; Noise/adverse effects; *Occupational Diseases/chemically induced/etiology/prevention & control; *Occupational Health; *Police; Risk Assessment; Risk Factors; Stress Disorders, Post-Traumatic/etiology; Stress, Psychological/etiology; Vibration/adverse effects
Abstract (down) The present paper tries to identify the occupational risk factors (physical, chemical, biological, psychological), variable depending on jobs and tasks, to which the heterogeneous public safety/security workers are exposed. The fight against criminality and public order maintenance imply (sometimes fatal) traumatic risks, and expose to psychophysical and sensorial tiring, unfavourable macro- and microclimatic conditions, the risk of baropathy (air navigation, underwater activities), noise (generated by firearms and several other sources), vibrations and shakings (automatic weapons, transport vehicles), the risk of electric injury, ionizing (X and gamma rays) and non-inonizing (ultraviolet rays, microwaves and radiofrequencies, electromagnetic fields) radiations. Chemical hazards include carbon monoxide and other combustion products (fires, urban traffic), substances released in chemical accidents, tear gases, lead (firing grounds, metal works, environmental pollution), solvents, lubrificants and cutting oils (mechanic repair and maintenance), laboratory materials and reagents, irritant and/or sensitizing agents contained in gloves. The main biological risks are tetanus, blood-borne diseases (viral hepatitis, AIDS), aerogenous diseases (e.g., tuberculosis, Legionnaire's disease, epidemic cerebrospinal meningitis), dog- or horse-transmitted zoonosis. Finally, emotional, psychosomatic and behavioural stress-related disorders (e.g., burn-out syndrome, post-traumatic stress disorder) are typically frequent. The presence of numerous and diversified hazards among public safety/security forces imposes the adoption of occupational medicine measures, including risk assessment, health education, technical and environmental prevention, personal protective devices, sanitary surveillance and biological monitoring, clinical interventions (diagnosis, therapy and rehabilitation of occupational accidents and illnesses), prompt medico-legal evaluation of occupational-related compensation claims.
Address Scuola di Specializzazione in Medicina del Lavoro, Universita degli Studi di Pavia, Italy
Corporate Author Thesis
Publisher Place of Publication Editor
Language Italian Summary Language Original Title Rischi professionali nelle Forze dell'Ordine
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1592-7830 ISBN Medium
Area Expedition Conference
Notes PMID:16705889 Approved no
Call Number Serial 1871
Permanent link to this record
 

 
Author Grandin, T.
Title Safe handling of large animals Type Journal Article
Year 1999 Publication Occupational Medicine (Philadelphia, Pa.) Abbreviated Journal Occup Med
Volume 14 Issue 2 Pages 195-212
Keywords Accidents, Occupational/*prevention & control/statistics & numerical data; Aggression/physiology/psychology; Animal Husbandry/*methods; Animals; *Behavior, Animal/physiology; Cattle; Conditioning, Operant/physiology; Crowding/psychology; Fear/physiology/psychology; Female; *Horses/physiology/psychology; Humans; Male; Movement/physiology; *Occupational Health; Risk Factors; *Ruminants/physiology/psychology
Abstract (down) The major causes of accidents with cattle, horses, and other grazing animals are: panic due to fear, male dominance aggression, or the maternal aggression of a mother protecting her newborn. Danger is inherent when handling large animals. Understanding their behavior patterns improves safety, but working with animals will never be completely safe. Calm, quiet handling and non-slip flooring are beneficial. Rough handling and excessive use of electric prods increase chances of injury to both people and animals, because fearful animals may jump, kick, or rear. Training animals to voluntarily cooperate with veterinary procedures reduces stress and improves safety. Grazing animals have a herd instinct, and a lone, isolated animal can become agitated. Providing a companion animal helps keep an animal calm.
Address Department of Animal Science, Colorado State University, Fort Collins 80526, USA
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0885-114X ISBN Medium
Area Expedition Conference
Notes PMID:10329901 Approved no
Call Number Equine Behaviour @ team @ Serial 3793
Permanent link to this record
 

 
Author Jackson, R.R.; Pollard, S.D.; Li, D.; Fijn, N.
Title Interpopulation variation in the risk-related decisions of Portia labiata, an araneophagic jumping spider (Araneae, Salticidae), during predatory sequences with spitting spiders Type Journal Article
Year 2002 Publication Animal Cognition Abbreviated Journal Anim. Cogn.
Volume 5 Issue 4 Pages 215-223
Keywords Animals; Female; Male; Mental Processes; *Predatory Behavior; Risk Factors; *Spiders
Abstract (down) The extent to which decision-making processes are constrained in animals with small brains is poorly understood. Arthropods have brains much smaller and simpler than those of birds and mammals. This raises questions concerning limitations on how intricate the decision-making processes might be in arthropods. At Los Banos in the Philippines, Scytodes pallidus is a spitting spider that specialises in preying on jumping spiders, and Portia labiata is a jumping spider that preys on S. pallidus. Scytodid spit comes from the mouth, and egg-carrying females are less dangerous than eggless scytodids because the female uses her chelicerae to hold her eggs. Held eggs block her mouth, and she has to release them before she can spit. The Los Banos P. labiata sometimes adjusts its tactics depending on whether the scytodid encountered is carrying eggs or not. When pursuing eggless scytodids, the Los Banos P. labiata usually takes detour routes that enable it to close in from behind (away from the scytodid's line of fire). However, when pursuing egg-carrying scytodids, the Los Banos P. labiata sometimes takes faster direct routes to reach these safer prey. The Los Banos P. labiata apparently makes risk-related adjustments specific to whether scytodids are carrying eggs, but P. labiata from Sagada in the Philippines (allopatric to Scytodes) fails to make comparable risk-related adjustments.
Address Department of Zoology, University of Canterbury, Private Bag 4800, Christchurch, New Zealand
Corporate Author Thesis
Publisher 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 PMID:12461599 Approved no
Call Number Equine Behaviour @ team @ Serial 2591
Permanent link to this record
 

 
Author Murray, J.K.; Singer, E.R.; Morgan, K.L.; Proudman, C.J.; French, N.P.
Title Risk factors for cross-country horse falls at one-day events and at two-/three-day events Type Journal Article
Year 2005 Publication The Veterinary Journal Abbreviated Journal
Volume 170 Issue 3 Pages 318-324
Keywords Horse; Eventing; Fall; Cross-country; Risk
Abstract (down) The cross-country phase of eventing competitions has been associated with injuries and fatalities to horses and riders. A case-control study was carried out to identify variables that were associated with increased or decreased risk of a horse fall on the cross-country phase at event competitions. After initial analysis, the dataset was split according to the categories of one-day events as compared to two- or three-day events to establish whether significant risk factors varied between the different types of eventing competitions. Data were collected for 121 cases (horse falls) at one-day events, 59 cases at two- or three-day events and for their 540 matched controls. The data were analysed using conditional logistic regression. The variables of no previous refusals on the course, fences with a landing in water and the combined variable of the angle and the spread of the fence were significantly associated with the risk of a horse fall in both datasets. Additional risk factors for one-day event falls were: fences requiring a take-off from water, a drop landing, the rider's knowledge of their position before the cross-country phase and if the rider received cross-country tuition. Three-day event risk factors in the multivariable model included: the camber of the fence and participation in non-equestrian sports by the rider. This study identified variables that were significantly associated with an increase or a decrease in the risk of a horse fall during the cross-country phase of different types of eventing competitions. Some of these variables are modifiable and the results of this study have been reported to the governing body of the sport of eventing in the UK so that possible interventions might be considered.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Equine Behaviour @ team @ Serial 3671
Permanent link to this record
 

 
Author Waters, A.J.; Nicol, C.J.; French, N.P.
Title Factors influencing the development of stereotypic and redirected behaviours in young horses: findings of a four year prospective epidemiological study Type Journal Article
Year 2002 Publication Equine veterinary journal Abbreviated Journal Equine Vet J
Volume 34 Issue 6 Pages 572-579
Keywords Age Factors; Animal Husbandry/*methods; Animal Welfare; Animals; *Behavior, Animal; Female; Horse Diseases/epidemiology/prevention & control/*psychology; Horses; Housing, Animal; Longitudinal Studies; Male; Prevalence; Prospective Studies; Risk Factors; *Stereotyped Behavior; Weaning
Abstract (down) Stereotypies are invariant and repetitive behaviour patterns that seemingly have no function, which tend to develop in captive animals faced with insoluble problems and may be indicative of reduced welfare. A 4 year prospective study of the factors influencing the development of stereotypic and redirected behaviours (abnormal behaviour) in a population of 225 young Thoroughbred and part-Thoroughbred horses was conducted between 1995 and 1999. Abnormal behaviour affected 34.7% of the population. Multivariable analysis showed that foals of low- or middle-ranking mares were less likely to develop abnormal behaviour than foals of dominant mares (rate ratio (RR) 0.23, P<0.01; RR 0.48, P<0.01, respectively). Weaning by confinement in a stable or barn was associated with an increased rate of development of abnormal behaviour, compared with paddock-weaning (RR 2.19, P<0.05), and housing in barns, rather than at grass after weaning, was associated with a further increase (RR 2.54, P<0.01). Specific stereotypic and redirected behaviours were then considered as separate outcomes. Crib-biting was initiated by 10.5% of horses at median age 20 weeks, weaving by 4.6% of horses at median age 60 weeks, box-walking by 2.3% of horses at median age 64 weeks and wood-chewing by 30.3% of horses at median age 30 weeks. Wood-chewing developed at a lower rate in horses born to subordinate or mid-ranking mares than in horses born to dominant mares (RR 0.29, P<0.01; RR 0.41, P<0.01, respectively), and at a higher rate in horses kept in barns or stables rather than at grass after weaning (RR 4.49, P<0.001; RR 1A6, P<0.001, respectively). Feeding concentrates after weaning was associated with a 4-fold increase in the rate of development of crib-biting (RR 4.12, P = 0.02). The results of this study support the idea that simple changes in feeding, housing and weaning practices could substantially lower the incidence of abnormal behaviour in young horses.
Address University of Bristol, Department of Clinical Veterinary Science, Langford, Bristol, UK
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0425-1644 ISBN Medium
Area Expedition Conference
Notes PMID:12357996 Approved no
Call Number refbase @ user @ Serial 84
Permanent link to this record
 

 
Author Reluga, T.C.; Viscido, S.
Title Simulated evolution of selfish herd behavior Type Journal Article
Year 2005 Publication Journal of Theoretical Biology Abbreviated Journal J. Theor. Biol.
Volume 234 Issue 2 Pages 213-225
Keywords Selfish herd; Behavior; Evolution; Predation risk
Abstract (down) Single species aggregations are a commonly observed phenomenon. One potential explanation for these aggregations is provided by the selfish herd hypothesis, which states that aggregations result from individual efforts to reduce personnel predation risk at the expense of group-mates. Not all movement rules based on the selfish herd hypothesis are consistent with observed animal behavior. Previous work has shown that herd-like aggregations are not generated by movement rules limited to local interactions between nearest neighbors. Instead, rules generating realistic herds appear to require delocalized interactions. To date, it has been an open question whether or not the necessary delocalization can emerge from local interactions under natural selection. To address this question, we study an individual-based model with a single quantitative genetic trait that controls the influence of neighbors as a function of distance. The results indicate that predation-based selection can increase the influence of distant neighbors relative to near neighbors. Our results lend support for the idea that selfish herd behavior can arise from localized movement rules under natural selection.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number refbase @ user @ Serial 553
Permanent link to this record