Study of Seasonal Variations in Population Dynamics of Spider Families in Paddy Agro-Ecosystem, Sabour, Bhagalpur, Bihar, India

Ongoing study unveiled the seasonal variations in p opulation dynamics of various spider families and w eather parameter that correlate with crop age in the paddy agro ecosystem. A study was carried out at the B ihar Agricultural College Farm, Sabour, Bhagalpur, during Kharif seas on in 2014. Collections of spiders were initiated a t 15 Days After Transplanting (DAT), and were continued up to 105 D AT at fifteen days interval from the field size was 30X30 m. 10 double sweeps were done at a stretch and the collec ted spiders were kept in the separate plastic bottl e containing 70 % alcohol. This process was repeated five times at fi ve different places of the field. Population of dif ferent families was noted down and was correlated with the weather para meters like Temperature ( ̊C, maximum and minimum), Relative Humidity (% at 7 AM and 2 PM) and Rainfall (mm). We had found all the six spider families, the populat ion growth showed a gradual increase in the 15 , 30 and 45 DAT followed by a slight decrease in the 60 th DAT after which it continued to grow up to the 90 th DAT when it reached the peak and then showed a sud den decline at 105 DAT. The maximum relative humidity (%) had a significant and positive impact on the population of the spider fa milies namely Oxyopidae, Salicidae and Thomisidae. The other mete orological parameters were not found to have a sign ificant effect on the spider families.