From 1966 - 1970 he studied at the Kunstgewerbeschule (arts and crafts school) in Graz with Otto Bünner and from 1971 - 1976 at the Academy of Fine Arts, Vienna, with Walter Eckert., He has been a professor at the Academy of Fine Arts, Vienna since 2005. Bohatsch worked as a painter, graphic artist and designer and became a member of the "Neue Malerei" (New Painting) group at the beginning of his career in Austria and is usually considered as a "New Fauve" there. From the beginning, his artistic work has shown all features of "New Painting", such as a narrative, figuration and expression. Later Bohatsch changed his style, turning to abstraction and stood for a mythical-poetical commitment.
His first works reflect organic shapes in relief-like rooms and feature a spontaneous, expressive approach. In later works, he turned to abstraction, neglecting figurative elements. Besides dealing with abstraction, the artist also received the Color-Field Painting method. In more recent pictures, overlaid paint layers, drops and flow marks appear smoothened with a spatula, and the resulting bridges have become a characteristic feature of the painter. The contained textures appear transparent and glazed and cover the essence in an iconic manner. The repetitive painting mode makes Bohatsch's paintings appear like a long series with an open end. By changing from dark to light colors he aims to provide more openness and transparency to the paintings, since, according to Bohatsch, dark colors tend to "seal the pictures". Likewise, he dissolves symbolism and all concrete forms and aspires to beauty via unintentional gestures.
The painter was also commissioned to create a sculpture, which he named Wand sculpture, and which was installed at Österreichischer Skulpturenpark. In 1983, the artist was awarded the Monsignore Otto Mauer Prize and in 1996, the Prize of the City of Vienna. Exhibitions of the famous artist also took place in 1984 at the Museum of Modern Art, New York , in 1985 and 1988 at the New York Sharpe Gallery, in 1996 at the Albertina, Vienna and in 1998 at the Viennese Secession. In 1994, Bohatsch participated in the Biennial of Graphic Arts in Zagreb.