Seasonal Dynamics on Spider Population in Pathiramanal Island, Kerala, India: A Case Study

Impact of temperature, rainfall, and humidity varied across different seasons, and the spiders responded differently in each season. Spider community reaches its peak in growing season (October to January). The growing season is recorded as the period with average temperature, rainfall, and relative humidity and which is found to be more suitable for spider population to increase, because highest proportion of spiders is trapped during this season. Ecological factors diminished the spider fauna from February to May (dry season) with high temperature and then gradually decreased through June to September (rainy season) because of heavy rainfall. Correlation analysis of variables with species richness and number of individuals is tested to check the statistical significance between them. Season-wise dendrogram is plotted to show the similarity between the seasons. For the estimation of spider diversity in three different seasons, indices such as Fisher alpha diversity index, Shannon diversity index and Simpson’s diversity index are evaluated.