American Bittern Botaurus lentiginosus: an historic first for Essex
feathers of the upper tail coverts there were signs of mite damage where the barbs and barbules had
been eaten away from the shafts. Tail feathers look worn with distal edges bleached and irregular,
the base colour to the centre of the feathers is pale matt brown interspersed with slightly darker
markings. I could see no signs of gloss on any of the tail feathers I examined.
Bare Parts: Bill has a chocolate brown culmen ridge, most obvious at its distal end. Cutting surfaces
are more horn coloured. Lower mandible: basal two-thirds are horn-coloured with the distal third a
darker brown.
Age
The general worn state of the right hand tcrtials, lesser and median coverts, upper mantle, upper
scapulars, tail and outer primaries suggest that this is not a fresh juvenile bird. The worn tail feathers
with a lack of glossing also support this assumption.
Plumage characteristics that suggest this bird is an immature
If it had been an adult I would have expected broader, fresher looking tail feathers. The primary tips
would have had less bleaching and wear. Furthermore the tcrtials would have been broader, longer,
with less bleaching and with a richer base colour. Lastly the scapulars would have been fresh and
bright along their entire length.
When had it been collected?
The lack of really fresh feathering, except in a few limited areas of recent growth, suggests that the
bird had not been collected in the autumn. The apparently fresh lower scapulars and the growing
black malar feather on the left hand side of the neck suggest it is more likely to be in the spring. I
would therefore suggest that it is an immature obtained some time in the spring before it had completed
its moult and attained first-summer plumage.
Transcribed from a taped description 10/12/2000
Graham Ekins, 35 Church Road, Boreham, Essex CM3 3BN
40
Essex Naturalist (New Series) 19 (2002)