Notes on the swarming behaviour and population density of Asterias rubens L. (Echinodermata: Asteroidea) feeding on the mussel, Mytilus edulis L

Efficiency of starfish mopping in reducing predation on cultivated benthic mussels ( Mytilus edulis Linnaeus)

“…4 aggregations of starfish moving towards prey sources have noted particularly high densities of individuals within feeding fronts with 47 and 78 starfish m -2 being recorded on mussel beds in Morecambe Bay and the Wadden Sea respectively (Aguera et al, 2012;Dare, 1982;Saier, 2001).…”

“…Starfish within such dense populations act as highly efficient predators, increasing their consumption when they encounter high-density prey patches, with aggregations in Morecambe Bay having been noted to advance up to 200 m a month destroying mussel beds that lay in their path (Dare, 1982;Inglis and Gust, 2003). A rubens is thought to be one of the most destructive species feeding on beds of cultivated mussels, as well as on natural populations, in northern Europe (Dare, 1982;Gallagher et al, 2008).…”

“…A rubens is thought to be one of the most destructive species feeding on beds of cultivated mussels, as well as on natural populations, in northern Europe (Dare, 1982;Gallagher et al, 2008).…”

“…Although mops appear to remove starfish from mussel beds, there is scope to enhance efficiency. In addition, there is a need to better understand starfish population dynamics and feeding behaviour in relation to environmental factors and reproductive condition to help determine how mopping efforts could be more cost-effectively focussed both spatially and temporally Dare, 1982;Gallagher et al, 2008;Sloan and Aldridge, 1981). By attaching a GoPro™ video camera to starfish mops on a commercial mussel dredger working in Belfast Lough, Northern Ireland, we filmed the mussel bed being swept by the mops.…”

“…A. rubens, along with several other starfish species within the genus Asterias, exhibit large population density fluctuations and are known to form dense aggregations (Sloan, 1980;Uthicke et al, 2009). High densities of A. rubens have frequently been reported at numerous locations across Europe and Russia since a dense aggregation was first reported, feeding on oyster beds, in the Firth of Forth, Scotland in 1841 (Dare, 1982(Dare, , 1973Forbes, 1841;Guillou, 1996;Hancock, 1955;Saier, 2001;Sloan and Aldridge, 1981;Sloan, 1980). These dense starfish populations are often associated with an abundant prey source and are known to have significant impacts on associated communities (Aguera et al, 2012;Castilla, 1972;Uthicke et al, 2009).…”