Page 183 - Proceedings of the State Natural History Museum. Issue 37 (Lviv, 2021)

182 Khymyn M.V.

Materials and methods

Our research were conducted on the territory of NNP «Prypiat-Stokhid» at left (northern)
bank of the Prypiat River near Svalovychi village in Kamin-Kashyrsk district of Volyn region
of Ukraine (N 51°52' E 25°39') during the part of September until the beginning of the end
of 2nd decade of October 2012-2017. The number of observation days varied in different
years: 4-12.ІХ, 22.ІХ-20.2012, 09.ІХ-10.Х.2013, 22.ІХ-19.Х.2014, 21.ІХ-20.Х.2015,
19.ІХ-19.Х.2016, 18.ІХ-17.Х.2017 (1980 hours).
Visible autumn migrations were studied according to conventional method [3, 4] with
some of our changes and additions [7-11]. Migratory birds were observed visually, starting
in the morning half an hour before sunrise and ending in the evening half hour after sunset
(all hours of the light part of a day, without interruption). The width of the accounting corridor
for these birds was 1500 m (750 m to the left and right of the observatіon poіnt). The light
part of a day was divided into hour of observations (morning and day observation hours – №
1-11 and evening observation hours – № 2 і № 1), taking into the daily changes of sunrise
and sunset (observation time decreased daily by 1,5-2 min). All observation hours were
complete (a full hour), except last before evening hour (№ 11 – on beginning observations in
the September and № 10 – on ending observations in the October) which was incomplete
(less or more than 1 hour). Flight altitude was determined visually, and flight directions – by
8 rhumbs, taking into account the experience of other researchers [4]. All data on the number
of account birds of each species, altitude and direction on their flight during the observation
hour were recorded in a notebook. Species were determined visually and by voice. The
binoculars were used during observations of migratory birds. The photographing was
sometimes used to count the number of birds in large flocks. In addition, the time of
precipitation and wind directions were registered in observation hours. The weather data from
the Liubeshiv meteorological station was used and analyzed [7-11].
Statistics were processed in Microsoft Office Excel 2003.

Results and discussions

There were 2737 individuals of the Common Crane counted during the study of visible
autumn migration birds in 2012-2017 near the Svalovychi village (table 1).
There were different numbers of migratory birds in different years (the most was counted
in 2017 and the least in 2016). Almost all birds flew in flocks. Several single birds were
observed also, apparently lagging behind their flocks (see table 1). For the analysis of autumn
migrations of waterfowl, the total of birds counted for 2012-2017 was used.