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 the world. It has been extensively studied over the last 100 years or so, and examination of the literature reveals three striking features: (1) the presence of populations in a wide range of environmental conditions; (2) large 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 not explain what governs the observed temporal and spatial patterns of abundance, and the longevity or lifespan of populations. Understanding these features is necessary to predict how bloom populations might form. In a given habitat, the distribution and abundance of benthic marine invertebrates have been found to be maintained by four factors: larval recruitment (sexual reproduction), migration, mortality and asexual reproduction. The aims of this review are to determine the role of reproduction and life history strategies of the benthic and pelagic phases of A. aurita in governing populations of medusae, with special attention given to the dynamic interaction between A. aurita and its surrounding physical and biological environment.