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Study on the relation between an accipiter bird and man

100%

Tobolova R., Wietrow P., Kosiarz P., Glowacka A., Lukasiewicz M.

Annals of Warsaw University of Life Sciences - SGGW. Animal Science

2014

tom 53

Study on the relation between an accipiter bird and man. The aim of this study was to learn relations between accipitrids and men working with them. The study consisted in observations of trained accipitrids – common buzzard Buteo buteo and Northern goshawk Accipiter gentili, during everyday trainings, with special attention devoted to the role of sight in their life. As a result of observations made in the study, it was concluded that the visual and audio signal as well as knowing each other and common trust were important factors during man’s work with a raptor. Common buzzard turned out to be a calmer bird, its responses were less rapid compared to Northern goshawk. This raptor did not pay attention to the presence of unfamiliar persons, but was vulnerable to objects emitting signals unfamiliar to it (buses or moving trolleys). None of the hunting birds allowed to be touched by an unfamiliar person, which is a natural behavior of raptors. Northern goshawk was responding significantly faster to the sight of an approaching person and was flaying away almost immediately.

Body size relationships between avian predators and their rodent prey in a North-American sagebrush community

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Gliwicz J.

Acta Ornithologica

2008

tom 43

nr 2

151-158

Larger predators consume prey of greater mean size and include a wider diversity of prey in their diets than their smaller counterparts occurring in the same communities. There is some controversy as to whether these patterns result from opportunistic feeding behavior or from prey size selectivity leading to food-niche segregation among predators. This study examined the effects of body size on the diet of avian predators in the sagebrush habitat of north-eastern Utah. The assessment was based on data collected from the analysis of pellet contents and was deliberately confined to mammalian components, almost exclusively from rodents. A significant positive relationship was found between predator size and both average and maximum prey size, but no such correlation was found for the minimum body size of prey. In general, there was considerable overlap in the rodent prey taken by different raptors, suggesting opportunistic feeding behavior in these predators. However, the size (and species) of rodent prey that contributed most to the consumed biomass was different for each bird species and correlated well with its body size. The revealed pattern of larger raptors acquiring most biomass (energy) from larger prey, implies food selectivity based on its energetic profitability, and niche segregation that could facilitate the coexistence of a high diversity of avian predators in the sagebrush habitat. The possible role of food limitation and competition in the evolution of body size in raptors and the consequences of size-dependent predation are discussed.

Ograniczanie wyników

1 Acta Ornithologica

1 Annals of Warsaw University of Life Sciences - SGGW. Animal Science

1 Gliwicz J.

1 Glowacka A.

1 Kosiarz P.

1 Lukasiewicz M.

1 Tobolova R.

1 Wietrow P.

1 2014

1 2008

Wyniki wyszukiwania

Study on the relation between an accipiter bird and man

Body size relationships between avian predators and their rodent prey in a North-American sagebrush community