Reproduction and life history strategies of the common jellyfish, Aurelia aurita, in relation to its ambient environment

The scyphozoan Aurelia aurita (Linnaeus) is a cosmopolitan species, having been reported from a variety of coastal and shelf sea environments around t he world. It has been extensively studied over the last 100 years or so, an d examination of the literature reveals three striking features: (1) the pr esence of populations in a wide range of environmental conditions; (2) larg e inter-population differences in abundance and life history patterns over large and small spatial scales; and (3) inter-annual variability in various aspects of its population dynamics. A. aurita is clearly a highly flexible species that can adapt to a wide range of environmental conditions. While various physiological and behavioural characteristics explain how A. aurita populations can take advantage of their surrounding environment, they do n ot explain what governs the observed temporal and spatial patterns of abund ance, and the longevity or lifespan of populations. Understanding these fea tures is necessary to predict how bloom populations might form. In a given habitat, the distribution and abundance of benthic marine invertebrates hav e been found to be maintained by four factors: larval recruitment (sexual r eproduction), migration, mortality and asexual reproduction. The aims of th is review are to determine the role of reproduction and life history strate gies of the benthic and pelagic phases of A. aurita in governing population s of medusae, with special attention given to the dynamic interaction betwe en A. aurita and its surrounding physical and biological environment.