Many food hoarding animals live in small groups structured by rank. The presence of conspecifics in the hoarding area increases the risk of losing stored supplies. The possibility of stealing from others depends on a forager's rank in the group. Highly ranked individuals can steal from subordinates and also protect their own caches. Since storing incurs both costs and benefits, the optimal hoar...

The hypothesis that spatial-memory specialization affects the size of the hippocampus has become widely accepted among scientists. The hypothesis comes from studies on birds primarily in two families, the Paridae (tits, titmice and chickadees) and the Corvidae (crows, nutcrackers, jays, etc.). Many species in these families store food and rely on spatial memory to relocate the cached items. The...

To gain insights into the evolution and ecology of visually acute animals such as birds, biologists often need to understand how these animals perceive colors. This poses a problem, since the human eye is of a different design than that of most other animals. The standard solution is to examine the spectral sensitivity properties of animal retinas through microspectophotometry-a procedure that ...

Since the 1980s, a significant decline in number of breeding populations Rook, Corvus frugilegus Linnaeus, 1758, has been observed many European countries. In Ukraine, this trend since late 1990s. 2021, conservation status Rook Europe was significantly upgraded — from “LC” (Least Concern) to “VU” (Vulnerable). The analysis material surveys 1983–1985 and 2021 on territory 1850 km² Kyiv Region sh...

Introduction.As a result of consumer activity, household waste is generated, which stored in specially designated landfills. Such areas are factors multifunctional impact on the environment and characterized by release filtrate gases, various types air pollution, soils groundwater, transformation natural landscapes. The biotic component ecosystems responds most dynamically to changes landscape ...

The White-naped Jay Cyanocorax cyanopogon (Wied, 1821) is an omnivorous and opportunistic species, with a multifarious diet. In view of the scarcity of available data in the literature, the aim was to investigate and describe the bird's diet, location of food items, foraging tactics, actual feeding behavior and intraspecific interactions, as a means of defining the items consumed. The study was...