My brother, Alastair Robertson, who has died of cancer aged 75, drew compulsively from an early age, on any scrap of paper. When he lost the use of his right hand in an accident, he transferred his skills to his left. His acutely observed watercolour illustrations of wildlife against delicate backgrounds of washes were widely exhibited in the 1970s and 80s.
He also drew mammals, insects and fish, sometimes with humorous intent, but his passion was birds of prey: he kept a variety of hawks and falcons in his late teens and flew gyrfalcons at a US air force base to prevent bird strikes.
