The spread of Pisonia in former plantation on Bird Island has been rapid: in 1976,
only one tree was recorded (Stoddart and Fosberg 1981), but by 2000, there were
over a thousand individuals (Hill et al. 2001). The recent history of Denis has been
similar to that of Bird Island, with guano removal followed by coconut plantation
(Stoddart and Fosberg 1981). Cousin, although granitic, is dominated by a low
plateau of recent sands cemented by guano, and its flora strongly resembles those of
the coralline islands (Procter 1984; Schumacher and Wuthrich 2000).