Distribution and seasonal abundance of acarine community (Arachnida: Acari) in a Zoological Park of Darjeeling Himalayas, West Bengal, India

In this investigation an attempt has been made to study the species composition, distribution and seasonal fluctuation of acarine community (Arachnida: Acari) in two undisturbed and well-vegetated plots located within Padmaja Naidu Himalayan Zoolo-gical Park, Darjeeling, India. The study continued for three consecutive years (January to December 1999–2001) revealed the presence of 10 acarine genera of which six belonged to Oribatida and four to Mesostigmata. However no Prostigmata or Astigmata were recorded. In most of the samples Oribatida outnumbered the Mesostigmata. The total population of Acari during the period of study exhibited an irregular trend of fluctuation showing post winter or pre-monsoon maxima and monsoon minima. The Oribatida which dominated the population were the main contributor of the population abundance curve as observed in this study. Of the 4 edaphic factors (viz. pH, temperature, moisture and organic matter) studied, only the content of organic matter showed a significant and positive correlation with the population while the remaining three (viz. pH, temperature, moisture) had a negative correlation with the population. Both the plots were more or less identical in climatological, edaphological factors as well as vegetation cover with little variation in altitude and did not exhibit any significant variation in diversity index value.