Dumont, B., Rossignol, N., Loucougaray, G., Carrère, P., Chadoeuf, J., Fleurance, G., et al. (2012). When does grazing generate stable vegetation patterns in temperate pastures? Agriculture, Ecosystems & Environment, 153, 50–56.
Abstract: The stability of grazing-induced spatial patterns of vegetation was analyzed at two spatial scales (25 m × 20 m areas and 1.6 m × 0.8 m grids) in pastures of contrasting productivity (maximum standing biomass: 130–800 gDM/m2). At both scales, the mosaic of grazed and ungrazed patches was modeled as a Boolean process, calculating cross-variograms to quantify the temporal stability of grazing patterns and its links with local floristic composition were tested. The scale at which stability of vegetation patterns took place in two successive years depended on pasture productivity. Inter-annual stability of large-scale patterns mainly occurred in extensively used fertile pastures grazed by cattle, and in pastures grazed by horses. Less-fertile grasslands were mainly characterized by a fine-scale stability of grazing patterns. Stable fine-scale patterns were often related to the local abundance of legumes and forbs. Stable large-scale patterns of grazing within lightly grazed productive grasslands could result in divergent local vegetation dynamics, which can be seen as an opportunity for restoring biodiversity in fertile grasslands.
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Hrdy, S. B. (1974). Male-male competition and infanticide among the langurs (Presbytis entellus) of Abu, Rajasthan. Folia Primatol (Basel), 22(1), 19–58.
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Gauvin, S., & Giraldeau, L. - A. (2004). Nutmeg mannikins ( Lonchura punctulata) reduce their feeding rates in response to simulated competition. Oecologia, 139(1), 150–156.
Abstract: Group feeding animals experience a number of competitive foraging costs that may result in a lowered feeding rate. It is important to distinguish between reductions in feeding rates that are caused by reduced food availability and physical interactions among foragers from those caused by the mere presence of foraging companions that may be self-imposed in order to obtain some benefit of group membership. Starlings ( Sturnus vulgaris) reduce their feeding rates when in the company of simulated competitors located in an adjacent cage that cannot affect the food availability or interact with the forager. In the present study, we investigate whether the presence of simulated competitors in another species of passerine, nutmeg mannikins ( Lonchura punctulata), can result in self-imposed reductions in feeding rates. When feeding in the company of simulated competitors, mannikins spent more non-foraging time near them, fed more slowly, reduced travel times between patches, reduced their scanning time and pecked more slowly. These results provide evidence that simulated competitors induce a reduction in pecking rate: behavioural interference. These self-imposed responses to competitors may have resulted from attempts to remain close to the non-feeding companions. Such self-imposed reductions in feeding rates may be a widespread yet generally unrecognised foraging cost to group feeding individuals.
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Capela, R., Sousa, C., Pena, I., & Caeiro, V. (1993). Preliminary note on the distribution and ecology of Culicoides imicola in Portugal. Med Vet Entomol, 7(1), 23–26.
Abstract: Data on Culicoides imicola were obtained during studies carried out during the recent outbreak of African horse sickness in Portugal. The previous most northerly published record of C. imicola in Portugal was 38 degrees 40'N (Pegoes). In the present work the geographical distribution of this species is extended to the parallel of 41 degrees 17'N. We have also confirmed the continuous presence of adult C. imicola in Southern Portugal (Alentejo and Algarve) throughout the year. In the laboratory we obtained this species from a sample of cattle faeces and from another of soil contaminated with animal excreta. In relation to host association 57.37% of C. imicola were trapped in the vicinity of pigsties. Finally, we collected 11,463 Culicoides of which 12.47% were C. imicola.
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Benhajali, H., Richard-Yris, M. - A., Leroux, M., Ezzaouia, M., Charfi, F., & Hausberger, M. (2008). A note on the time budget and social behaviour of densely housed horses: A case study in Arab breeding mares. Appl. Anim. Behav. Sci., 112(1-2), 196–200.
Abstract: We observed a high-density herd (200 mares/ha) of 44 Arab breeding mares, while in a bare paddock in Tunisia. Twenty-minute animal focal samples and scan sampling were used to determine the time budget of the mares during the period from 9 a.m. to 3 p.m. and study their social behaviour. The data obtained reveal restricted behavioural repertoires with missing behaviour like rolling, allogrooming and lying down; unusual time budgets with a high frequency of locomotion that constitutes the most frequent activity (27.9 ± 19.47%) of the mares. Social interactions were restricted to agonistic interactions but despite the high stocking density, aggressions were not that frequent among mares.
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Cancedda, M. (1990). [Social and behavioral organization of horses on the Giara (Sardinia): distribution and aggregation]. Boll Soc Ital Biol Sper, 66(11), 1089–1096.
Abstract: In this paper some considerations on the environment of the 42 Kmq of the volcanic-basaltic Giara tableland are discussed. Conditioning by the environment and its effect on the distribution of a population of 712 horses is illustrated in view of their social and behavioural organization.
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Nicol, C. J., Brown, S. N., Glen, E., Pope, S. J., Short, F. J., Warriss, P. D., et al. (2006). Effects of stocking density, flock size and management on the welfare of laying hens in single-tier aviaries. Br Poult Sci, 47(2), 135–146.
Abstract: Management practices, stocking rate and flock size may affect laying hen welfare but there have been few replicated studies in commercial non-cage systems that investigate this. This study used a broad range of physical and physiological indicators to assess the welfare of hens in 36 commercial flocks. Six laying period treatments were examined with each treatment replicated 6 times. It was not possible to randomly allocate treatments to houses, so treatment and house were largely confounded. Three stocking rates were compared: 7 birds/m(2) (n = 2450), 9 birds/m(2) (n = 3150) and 12 birds/m(2) in either small (n = 2450) or large (n = 4200) flocks. In addition, at 12 birds/m(2), in both small and large flocks, birds were subjected to either standard (SM) or modified (MM) management. MM flocks had nipple drinkers and no nest-box lights. Bone strength, fracture incidence, heterophil:lymphocyte (H:L) ratio, live weight, organ weights, serum creatine, serum osmolality, muscle pH and faecal corticosterone were measured on samples of birds at the end of the rearing period and at the end of lay. During the laying period, mortality, production and integument condition were recorded at regular intervals. Birds housed at 9 birds/m(2) had higher mortality than birds housed at 12 birds/m(2) by the end of lay, but not higher than birds housed at 7 birds/m(2). Birds housed at 7 and 9 birds/m(2) had lower percent liver weight, and worse plumage condition than most of the 12 bird/m(2) treatments. Modified management tended to improve plumage condition. There were no clear effects of flock size on the welfare indicators recorded. At the end of the rearing period fracture incidence was almost negligible and H:L ratio was within a normal range. By the end of lay fracture incidence was 60% and H:L ratio was high, with no treatment effect for either measure. This, together with information on faecal corticosterone, feather loss and mortality, suggests that the welfare of birds in all treatments was relatively poor by the end of lay.
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Judge, P. G., & de Waal, F. B. (1994). Intergroup grooming relations between alpha females in a population of free-ranging rhesus macaques. Folia Primatol (Basel), 63(2), 63–70.
Abstract: Intergroup affiliation among female rhesus macaques, Macaca mulatta, was examined in the captive free-ranging colony of Morgan Island, S.C., USA. The provisioned colony has many social groups (35) and is maintained at a relatively high population density (21 animals/ha) with a relatively low adult male to female ratio (1:8.8). Focal and ad libitum samples were collected on 32 adults (3 males and 29 females) from two groups. Although infrequent, grooming was observed between adult females from different groups, and alpha females were the main participants in these interactions. Colony records indicated that none of the intergroup grooms was between females formerly from a common group. Relations between familiar neighboring groups may be maintained by a combination of both affiliative and aggressive behavior.
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Linklater, W. L., Cameron, E. Z., Stafford, K. J., & Veltman, C. J. (2000). Social and spatial structure and range use by Kaimanawa wild horses (Equus caballus: Equidae). New Zealand J. Ecol., 24(2), 139–152.
Abstract: We measured horse density, social structure, habitat use, home ranges and altitudinal micro-climates in the south-western Kaimanawa ranges east of Waiouru, New Zealand. Horse density in the Auahitotara ecological sector averaged 3.6 horses.km-2 and ranged from 0.9 to 5.2 horses.km-2 within different zones. The population's social structure was like that of other feral horse populations with an even adult sex ratio, year round breeding groups (bands) with stable adult membership consisting of 1 to 11 mares, 1 to 4 stallions, and their predispersal offspring, and bachelor groups with unstable membership. Bands and bachelor males were loyal to undefended home ranges with central core use areas. Band home range sizes varied positively with adult band size. Home ranges overlapped entirely with other home ranges. Horses were more likely to occupy north facing aspects, short tussock vegetation and flush zones and avoid high altitudes, southern aspects, steeper slopes, bare ground and forest remnants. Horses were more likely to be on north facing aspects, steeper slopes, in exotic and red tussock grasslands and flush zones during winter and at lower altitudes and on gentler slopes in spring and summer. Seasonal shifts by bands to river basin and stream valley floors in spring and higher altitudes in autumn and winter are attributed to the beginning of foaling and mating in spring and formation of frost inversion layers in winter. Given horse habitat selectivity and the presence of other ungulate herbivores, results from present exclosures are likely to exaggerate the size of horse impacts on range vegetation. Proposals to manage the population by relocation and confinement are likely to modify current social structure and range use behaviour and may lead to the need for more intensive management in the longer term.
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McHugh, C. P. (1989). Ecology of a semi-isolated population of adult Anopheles freeborni: abundance, trophic status, parity, survivorship, gonotrophic cycle length, and host selection. Am J Trop Med Hyg, 41(2), 169–176.
Abstract: A population of adult Anopheles freeborni near Sheridan, CA was sampled daily during 13 August-7 September 1984. Data on abundance, trophic status, and gonotrophic age were recorded. Abundance and gonotrophic age data were analyzed to estimate daily survivorship and gonotrophic cycle length. Daily survivorship for unfed mosquitoes was estimated to be 0.72 with a gonotrophic cycle of 6 days duration. Daily survivorship for bloodfed mosquitoes was estimated to be 0.74 with a gonotrophic cycle of 4 days. The 2 day difference in gonotrophic cycles between unfed and bloodfed mosquitoes was the result of the period required for maturation and mating of teneral females. In 1986, an incage release of field-collected females estimated survivorship at 0.75 per day. Precipitin tests of 1,338 blood-engorged mosquito abdomens indicated that bovids, horses, rabbits, and canids comprised 92% of bloodmeals; no bloodmeals of human origin were detected.
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