Effects of water mite parasitism on the fitness of Enallagma hageni

Natural History & EvolutionDamselflies are entwined in a parasitic relationship with water mites. This parasitic relationship between organisms benefits one while harming the other – the water mite adversely affects the damselfly. As the frequency of water mites on its host increases, the subsequent the fitness of a damselfly decreases. Damselfly mass and date of collection served as independent variable to investigate the parasitic relationship between the water mite of genus Arrenurus and the damselfly, Enallagma hageni. This study was accomplished by capturing E. hageni on different days at the same test site and quantifying mite frequency, mating status, and body weight in each sample. After tabulation of collected specimens, data was analyzed in Excel and SPSS, to determine relationships among tested variables. The study of parasitism disclosed an inverse correlation between damselfly weight and water mite frequency. As concluded by the Poisson test, the study was biased regarding the formation of a parasitic relation between water mites and damselflies. Studies also revealed a negative temporal relationship between the date water mites parasitize a host and mite load. Based on this, damselflies were concluded to lose fitness with an increasing number of mites due to reduced damselfly mass and mass-related reproductive success. The study also deduced damselfly immunity increases with date of mite parasitizing damselflies, correlating an increase in fitness.http://deepblue.lib.umich.edu/bitstream/2027.42/57552/1/Patel_Sohil_2007.pd