The nesting ecology of the Corvus orientalis in Tuva and Buryatia

The ecological features of the eastern black crow Corvus orientalis breeding in the conditions of Tuva and Buryatia are revealed. The species is distinguished by high ecological plasticity, which allows it to inhabit in various natural and anthropogenic landscapes, including settlements of different types. Various types of trees are used for the construction of nests, but conifers are preferred and poplar. They rarely nest on power transmission lines. They nest in single pairs or form small settlements. The black crow is one of the early nesting birds in the region. Nesting begins at the end of March. The main proportion of birds lays eggs before the onset of the phenological summer, starting on April 8–15. Clutches are protected from low temperatures by a warmed nest and incubation from the first egg. The total duration of the nesting period in the region is 100–106 days, as for one pair of birds it is 56–60 days (laying eggs – 5–7 days, incubation – 19–20 days, staying of chicks in the nest – 27–29 days). The nesting period ends by July 20–25. Feeding of chicks coincides in time with the massive appearance of arthropods and, in particular, of Orthoptera, the main objects of their food. The nesting efficiency of the black crow is very high – 93,1%. All these data confirm a wide adaptive potential of the eastern black crow.