Bird turned over eggs etc when disturbed (6)
I believe the answer is:
avocet
'bird' is the definition.
(avocet is a kind of bird)
'turned over eggs etc when disturbed' is the wordplay.
'turned over' says the letters should be written in reverse.
'eggs' becomes 'ova' (I've seen this before).
'when disturbed' is an anagram indicator.
'ova' in reverse letter order is 'avo'.
'etc' is an anagram of 'cet'.
'avo'+'cet'='AVOCET'
(Other definitions for avocet that I've seen before include "Might it sing" , "Long-legged shorebird with upward-curving bill" , "ornithological specimen" , "Black-and-white shorebird with upward-curving bill" , "Wading bird with curved bill" .)