Effect of Habitat Structure on Odonate Species Richness in Streams of Kalakkand Mundanthurai Tiger Reserve in Tamil Nadu India

Abstract

This study aimed at the responses of species richness of Odonates toward the habitat structure in Kalakkad Mundanthurai Tiger Reserve(KMTR) in Tamil Nadu, India. KMTR lies between latitudes 8° 25' to 8° 53' N and longitudes 77°10' to 77° 35' E with altitude ranging from 50 meters to 1868 meters. Intensive study areas were confined to three beats in Mundanthurai and Kalakkad ranges of KMTR namely Kodamadi, Kannikatti and Sengaltheri. We sampled vegetation and stream structural parameters along with altitude and time of sampling from three drainages, River Thamiraparni, River Servalar and River Kil Manimuthar. Only the second, third and fourth order streams were sampled. Thirty six belt transects were laid and each transect was walked trice. A total of thirty six species were found during the study period. Species richness was calculated using Software· Estimate S version 0.8 and used to do GLM(Generalized Linear Model) in Software R version 3.0.1. Altitude was found to be the most influencing factor on species richness. A second GLM was carried out for the altitude wise stratified data incorporating temporal replicates for each transect. Tree height and stream width were found to be the most influencing factors in this model with p values 0.00007 and 0.001 respectively.