Eurasian Bittern
Botaurus stellaris

>> GENERAL >>>>>

– fairly large and stocky Heron, smaller than Grey Heron
– nocturnal migrant
– migrates singly, occasionally in very small flocks

>> VISUAL ID >>>>>


Eurasian Bittern Botaurus s. stellaris, AD F
BIF2878, 08/06/2015, Dänkritz, Germany, Jens Halbauer
– rather stocky heron with owl-like plumage, base colour yellow brown like old reed
– comparatively short legs, the large greenish feet protruding the tail
– three generations of primaries indicating an AD bird


Eurasian Bittern Botaurus s. stellaris, AD F
BIF2879, 08/06/2015, Dänkritz, Germany, Jens Halbauer
– upperwing with dark brown – reddish brown barring
– primary coverts darkest part of the wing
– sexed as F by greenish brown bare skin at the base of the bill and less contrasting dark cap and moustacial stripe


Eurasian Bittern Botaurus s. stellaris, AD F
BIF2880, 12/06/2013, Dänkritz, Germany, Jens Halbauer
– throat with dark brown stripes
– Greater and median coverts form a somewhat paler wing panel


Eurasian Bittern Botaurus s. stellaris, AD M
BIF2881, 11/05/2015, Dänkritz, Germany, Jens Halbauer
– note legs appear longer than usual due to damaged tail
– sexed as M by blueish bare skin at the base of the bill (only possible during breeding season)
– in M black cap and moustachial stripe tend to be more contrasting than in F


Eurasian Bittern Botaurus s. stellaris
BIF2882, 12/06/2013, Dänkritz, Germany, Jens Halbauer
– silhouette in twilight resembles Black-crowned Night Heron, but note longer legs
– bill in level with body axis
– larger, heavier appearance and slower wingbeats than Black-crowned Night Heron


Eurasian Bittern Botaurus s. stellaris, AD F
BIF2883, 02/07/2014, Dänkritz, Germany, Jens Halbauer
– compared to Purple or Grey Heron the neck is less sagging

>> ACOUSTIC ID >>>>>

– slightly downslurred, very nasal sounding, single calls
– energy centre at around 1,1kHz
– on average 3ms long
– rather invariable
– dense and even partials
– gaps between calls sometimes a few seconds long


– overview –

Eurasian Bittern Botaurus s. stellaris, calls in flight
BIF3133, 13/11/2019, Shirvan NP, Azerbaijan, Georg Rüppel


– overview –

– detail –
Eurasian Bittern Botaurus s. stellaris, calls in flight
BIF3134, 12/11/2019, Shirvan NP, Azerbaijan, Georg Rüppel


– detail –

– full overview –
– gaps between calls shortended –

Eurasian Bittern Botaurus s. stellaris, calls in flight
BIF2900, 20/08/2018, Helgoland, Roland Neumann


– detail –

– full overview –
– gaps between calls shortended –

Eurasian Bittern Botaurus s. stellaris, calls in flight
BIF2899, 09/05/2011, Ertis, Kazakhstan, Patrick Franke

>> COMPARISON SPECIES >>>>>

Purple Heron (v) (a)
Grey Heron (v) (a)
Black-crowned Night Heron (v) (a)
Greater Black-backed Gull (a)

#waterbird

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