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Ben-Shahar, R. (1995). Habitat classification in relation to movements and densities of ungulates in a semi-arid savanna. Afr. J. Ecol., 33, 50–63.
Abstract: Habitat types were classified in a semi-arid nature reserve in South Africa in order to assess the spatial requirements of resident ungulates, namely zebra, wildebeest and impala. Multivariate analyses showed patterns of soil factors and plant species associations that corresponded with variations of local geological formations and the abundance of plants. The response of ungulates to habitats of different degrees of complexity in terms of soils and plant species associations was examined on the basis of annual occurrence. New habitat types were described through merging or subdividing the existing classification. New habitat categories which corresponded with high occurrences of ungulates provided better indications of the resource requirements for large herbivores. Wildebeest were restricted in their habitat requirements and were characterized by high seasonal densities in bottom lands, particularly during the late wet period. There was a considerable overlap in the preference of habitat types between wildebeest and zebra although zebra were aggregated during longer periods within the dolerite formation. Impala had a consistent annual preference for the granite formation where seepage lines and bottom lands were inhabited seasonally by large herd concentrations.
Résumé On a classifié les types d'habitat dans une réserve naturelle semiaride d'Afrique du Sud, dans le but d'évaluer les exigences spatiales des ongulés qui y vivent, c'est à dire les zèbres, les gnous et les impalas. Des analyses multivariées ont révélé des schémas pour les facteurs du sol et pour les associations d'espèces végétales qui correspondent aux variations des formations géologiques locales et à l'abon-dance des plantes. On a examiné la réponse des ongulés à des habitats de complexité différente en termes de sols et d'associations d'espéces végétales, d'après leur présence annuelle. On a décrit de nouveaux types d'habitats en fusionnant ou en subdivisant la classification existante. Les nouvelles catégories d'habitats qui correspondaient à des présences abondantes d'ongulés ont fourni de meilleures indications sur les ressources exigées par les grands herbivores. Les gnous se limitaient aux endroits qui répondaient a leurs exigences et se caractérisaient par de hautes densités saisonnières dans les régions basses, spécialement pendant la dernière saison des pluies. Il y avait un recouvrement considérable des types d'habitats préferés par les gnous et les zébres, encore que les zébres se rassemblent plus longtemps dans la formation doléritique. Les impalas marquent une préférence annuelle constante pour la formation granitique où les sources et les terres basses sont occupées de façon saisonnière par des hardes très concentrées. |
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Meriggi, A., & Lovari, S. (1996). A Review of Wolf Predation in Southern Europe: Does the Wolf Prefer Wild Prey to Livestock? J. Appl. Ecol, 33, 1561–1571.
Abstract: 1. The recent recovery of the wolf in southern Europe has not yet removed the risk
of local extinction. Wolf populations are fragmented and often comprise fewer than 500 individuals. In North America, northern and eastern Europe, wolves feed maiiily on wild herbivores. In southern Europe, this canid has apparently adapted to feed also on fruit, rubbish, livestock, small and medium-size mammals. 2. The main conservation problem lies with predation o n domestic ~ingulates,w liich leads to extensive killing of wolves. The reintroduction of wild large herbivores has been advocated as a means of reducing attacks on livestock, but predatiori on the latter may remain high if domestic ungulates are locally abundant. 3. Our synthesis of 15 studies, published in the last 15 years, on food habits of the wolf in southern Europe, has shown that ungulates have been the main diet component overall. A significant inverse correlation was found between the occurrence (%) of wild and domestic ungulates in the diet. The presence of relatively few wild ungulate species was necessary to reduce predation on livestock. 4. Selection of wild and domestic ungulate prey was influenced mainly by their local abundance, but also by their accessibility. Feeding dependence on rubbish was local and rare. In Italy, the consumption of riibbish/fruit and that of ungulates was significantly negatively correlated. Diet breadth increased as the presence of large prey in tlie diet decreased. 5. The simultaneous reintroduction of severa1 wild ungulate species is likely to reduce predation on livestock and may prove to be one of the most effective conservation measures. |
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Krcmar, S., Mikuska, A., & Merdic, E. (2006). Response of Tabanidae (Diptera) to different natural attractants. J Vector Ecol, 31(2), 262–265.
Abstract: The response of female tabanids to natural attractants was studied in the Monjoros Forest along the Nature Park Kopacki rit in eastern Croatia. Tabanids were caught in canopy traps baited with either aged cow, horse, sheep, or pig urine and also in unbaited traps. Tabanids were collected in a significantly higher numbers in traps baited with natural attractants compared to unbaited traps. The number of females of Tabanus bromius, Tabanus maculicornis, Tabanus tergestinus, and Hybomitra bimaculata collected from canopy traps baited with cow urine and traps baited with other natural attractants differed significantly. Females of Haematopota pluvialis were also collected more frequently in canopy traps baited with aged cow urine than in those with aged horse urine, but this difference was not significant. However, the number of females of Haematopota pluvialis collected from canopy traps baited with other natural attractants (sheep and pig urine) differed significantly when compared with aged cow urine baited traps. Canopy traps baited with aged cow urine collected significantly more Tabanus sudeticus than did traps baited with aged pig urine. Finally, the aged cow urine baited canopy traps collected 51 times more tabanids than unbaited traps, while aged horse, aged sheep, and aged pig urine baited traps collected 36, 30, and 22 times as many tabanids, respectively, than unbaited traps.
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Negi, G. C. S., Rikhari, H. C., Ram, J., & Singh, S. P. (1993). Foraging Niche Characteristics of Horses, Sheep and Goats in an Alpine Meadow of the Indian Central Himalaya. J. Appl. Ecol, 30(3), 383–394.
Abstract: 1. Data on plant species foraged, foraging hours, bite rate, bite size and species dry matter (DM) removed per species per bite were collected in tussock grass-forb (Grass-F), forb-tussock grass (Forb-G), Trachydium-forb (Forb), Rhododendron-Cassiope and early successional communities from May to September in a moderately foraged Central Himalayan alpine meadow in order to study the foraging niche characteristics of horses, sheep and goats. 2. The three animals together grazed 30 plant species, of which 20 were grazed by horses, 22 by sheep and 16 by goats. 3. The average foraging hours (5.2-13.2), bites per minute (23-51) and mg DM per bite (59-99) for horses, sheep and goats were significantly different in different communities and months. 4. The foraging search cost, reckoned as distance walked per unit DM eaten, was highest for goats (15.4 km kg$^{-1}$), followed by sheep (8.1 km kg$^{-1}$) and horses (1.2 km kg$^{-1}$). 5. Of the total intake of horses (3.25 kg DM day$^{-1}$), the Forb community alone accounted for 40%. Sheep (0.74 kg DM day$^{-1}$) resembled horses in this respect. In contrast, the contribution of this community was negligible in the diet of goats in which the Grass-F community contributed most to the intake. 6. Forbs were the largest dietary category for all animal species. The selection ratio varied from 0.7 to 11.3 for forbs, 1.0 to 7.2 for sedges and 1.1 to 2.5 for grasses. 7. Response breadth (in terms of species grazed) was similar for horses and sheep (0.46 vs. 0.43) and somewhat wider for goats (0.49). 8. Grazing pressures below the carrying capacity of the community appeared to favour botanical diversity.
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Krause, J., Bumann, D., & Todt, D. (1992). Relationship between the position preference and nutritional state of individuals in schools of juvenile roach (Rutilus rutilus). Behav. Ecol. Sociobiol., 30(3), 177–180.
Abstract: Position preferences of well-fed and food-deprived juvenile roach were investigated in schools of 2 and 4 fish in the laboratory. Food-deprived fish appeared significantly more often in the front position than their well-fed conspecifics. For fish at the same hunger level, individuals at the front of the school had the highest feeding rate. These results represent the first evidence for a relationship between the nutritional state of individual fish and their positions in a school and suggest a functional advantage of the preference.
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Dugatkin, L. A. (1991). Dynamics of the TIT FOR TAT strategy during predator inspection in the guppy (Poecilia reticulata). Behav. Ecol. Sociobiol., 29(2), 127–132.
Abstract: One well-known solution to the iterated Prisoner's Dilemma is the TIT FOR TAT strategy. This strategy has three “characteristics” associated with it. TIT FOR TAT is nice (cooperates on the first move of a game), retaliatory (plays defect against an individual that defected on the prior move), and forgiving (cooperates with an individual which has defected in the past but cooperates in the present). Predator inspection behavior in guppies (Poecilia reticulata) was examined in order to determine whether guppies displayed these three characteristics. Results indicate that while it can be quite difficult to translate the abstract concepts of niceness, retaliation, and forgiveness into measurable behaviors, the data support the hypothesis that guppies display the three characteristics associated with the TIT FOR TAT strategy.
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Ben-Shahar, R. (1991). Selectivity in large generalist herbivores: feeding patterns of African ungulates in a semi-arid habitat. Afr. J. Ecol., 29(4), 302–315.
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. Keywords: diet; forage production; grazing; wildebeest; zebra
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Kirkpatrick, J. F., & Turner, J. W. (1991). Changes in herd stallions among feral horse bands and the absence of forced copulation and induced abortion. Behav. Ecol. Sociobiol., 29(3), 217–219.
Abstract: Forced copulation and induced abortion were investigated in a herd of feral horses inhabiting a coastal barrier island. Eight mares were diagnosed pregnant in August and October 1989 by means of urinary and fecal steroid metabolites, prior to documented changes in herd stallions. These mares were observed for harassment and forced copulation by the new stallions and for the presence of foals during the spring and summer of 1990. No incidents of harassment or attempts at forced copulation were witnessed and seven of the eight mares produced foals in 1990. These data indicate that forced copulation and induced abortion are not common events among all feral horse herds and suggest reinvestigation of this hypothesized phenomenon.
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Dugatkin, L. A., & Alfieri, M. (1991). Guppies and the TIT FOR TAT strategy: preference based on past interaction. Behav. Ecol. Sociobiol., 28(4), 243–246.
Abstract: The evolution of cooperation requires either (a) nonrandom interactions, such that cooperators preferentially interact with other cooperators, or (b) conditional behaviors, such that individuals act cooperatively primarily towards other cooperators. Although these conditions can be met without assuming sophisticated animal cognition, they are more likely to be met if animals can remember individuals with whom they have interacted, associate past interactions with these individuals, and base future behavior on this information. Here we show that guppies (Poecilia reticulata), in the context of predator inspection behavior, can identify and remember (for at least 4 h) the “more cooperative” among two conspecifics and subsequently choose to be near these individuals in future encounters.
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Meriggi, A., Dagradi, V., Dondina, O., Perversi, M., Milanesi, P., Lombardini, M., et al. (2014). Short-term responses of wolf feeding habits to changes of wild and domestic ungulate abundance in Northern Italy. Ethology Ecology & Evolution, 27(4), 389–411.
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