Effects of weather and phenology on the abundance and diversity of geometroid moths in a natural Malaysian tropical rain forest

Geometroid moth abundance, species richness, weather and plant phenology we re monitored monthly for 3 y in the lowland dipterocarp forest at Pasoh For est Reserve, Negeri Sembilan in Malaysia. The intensity of tree flowering i n the previous month (with mass events triggered in response to El Nino Sou thern Oscillations) was an important environmental factor positively correl ated with the numbers of species and individuals of geometroid moths that e merge in any month. Abundance for geometroid moths was greater in months wi th high flowering and flushing in the previous month but low flowering in t he month before that. Important weather parameters that influenced moth abu ndance were monthly rainfall, relative humidity and minimum temperature in previous months. High rainfall 3 mo previously led to all increase in moth abundance (perhaps by stimulating an increase in fresh plant material), whe reas high rainfall and relative humidity thereafter served to decrease abun dance, possibly by encouraging the spread and activity. of pathogens: all t hese factors impacted on early life-stage survivorship,. Similar trends wer e observed for individual geometroid families and subfamilies. The diversit y measurement for the geometroid moths, ct from the log-series, was correla ted more with weather parameters than with tree phenology.