K
zloženiu potravy a potravnej ekológii
trasochvosta žltého (Motacilla flava) na
západnom Slovensku On food composition and foraging ecology of
the Western Yellow Wagtail (Motacilla
flava) in Western Slovakia
Ján KOČÍ Ulica E. F. Scherera 36, 921 01 Piešťany,
Slovakia
Abstract:
The Western Yellow Wagtail (Motacilla flava)
is typical species of agricultural landscapes,
where the food supply is significantly
limited. The nestling diet composition and its
foraging ecology are little known in the
entire range. Therefore, we studied the
composition of the nestlings’ food and some
aspects of its foraging ecology by photos from
the shelter, in a population on abandoned
agricultural land (17 ha) in Western Slovakia
near Piešťany town (48,55098° N, 17,805612° E,
150 m asl.) in April–July 2017–2022. Analyzing
177 photos/feedings of young (1–12 days old)
by a male and a female in 9 nests, was found a
total of 361 prey items (2.7% of them
unidentified). The food consisted of
invertebrates from 12 orders, 33 families, and
approximately 86 species. Spiders (Araneida,
19.4%), crickets and grasshoppers (Orthoptera,
18.6%), and moths (Lepidoptera) and dipterans
(Diptera) with the same proportion 15.2%,
belonged to the eudominant prey groups. Among
the dominant and frequent species were, e. g.,
the aposematically coloured spider Argiope
bruenichii, the mayfly Ephemera danica, the
bush-crickets Leptophyes albovittata,
Bicolorana bicolor, from other taxa there were
significantly represented Noctuidae and
Geometridae caterpillars, cicadas
(Cicadellidae) and flies from the suborder
Nematocera. The prey body length varied
between 2 mm (snail Vallonia pulchella) and 50
mm (dragonfly of the genus Sympetrum) (average
17.1±8.6 mm, n = 361), i.e. it was on average
longer than the average bill length (11–12
mm). Parents brought 1–10 prey items per
feeding (mean = 2.0±1.5 items/ feeding, ca.
50% >1 object/ feeding, n = 177), the
species thus belongs to the group of the
“multiple prey loaders”. The size of foraging
territories and the role of the parents in
chick feeding was studied in one nest in 2022.
Citácia / Cite as
Kočí J. & Krištín A.: On food composition and
foraging ecology of the Western Yellow Wagtail (Motacilla
flava) in Western Slovakia.
Tichodroma 34: 63–69. DOI:
10.31577/tichodroma.2022.34.8