A review of the biology, ecology and potential use of the common ragworm Hediste diversicolor (O.F. Müller) (Annelida: Polychaeta)

Abstract

The common ragworm Hediste diversicolor inhabits the shallow marine and brackish waters in the North Temperate Zone of the Atlantic. This infaunal species builds U or Y-shaped burrows in the soft sediments. H. diversicolor is gonochoristic and remains atokous throughout its life. Due to the facility of harvesting of individuals by hand and their maintenance, this species represents a good biological material for experimental studies. In consequence, the common ragworm served as a model for endocrine control of reproduction in Polychaeta and played a fundamental role in the study of immune defence in Polychaeta. Life history characteristics (longevity, spawning season, feeding tactics and growth) and population dynamics (sex ratio, density and biomass) vary greatly according to geographical location of the populations. In addition, inter-population morphological, biochemical and physiological differences have been noticed in individuals from different areas and different environmental conditions in the same areas and could be related to the limited dispersal capacity of the species. H. diversicolor interacts with its environment. The construction of burrows by individuals increases the sediment-water interface. When they ventilate their burrows, individuals verticalize oxic zones into the sediment and promote microbial and meiofaunal growth alongside their burrows. Moreover, the common ragworm is a species of commercial interest because of its use as bait in recreational fishing and as food in aquaculture. In order to alleviate environmental pressure caused by excessive demand over optimal sustainable yield of bait fisheries, intensive aquaculture has been proposed. The common ragworm could be also used as biomonitor of pollution in estuarine ecosystems.