Drilling by Octopus vulgaris(Mollusca: Cephalopoda) in the Mediterranean

Abstract

Octopus vulgaris drills holes in the shells of a variety of molluscs. The walls of the cavities drilled exhibit dissolution of mineral and organic material. The features which characterize the cavities have been described. The composition and structure of the shell itself is important in determining the size, shape and form of the cavity drilled, and not the size of the octopus. Capture, drilling the shell, and eating the occupant may take less than one hour.

An Overview of Predation Evidence Found on Fossil Decapod Crustaceans With New Examples of Drill Holes Attributed to Gastropods and Octopods

“…3), with the outer drill-hole diameters usually being ,1 mm (Table 3), which is comparable to, and somewhat smaller than, those found in extant decapods (see Boyle and Knobloch, 1981;Nixon and Boyle, 1982;Guerra and Nixon, 1987;Mather and Nixon, 1995), and smaller than those observed in mollusks (e.g., Arnold and Arnold, 1969;Nixon and Maconnachie, 1988). The form and size of these drill holes conform with drill holes produced by octopods and reported from extant invertebrates including decapods, even though variation exists in the shape and form of these drill holes (e.g., Arnold and Arnold, 1969;Boyle and Knobloch, 1981;Nixon and Maconnachie, 1988). Bromley (1993) erected the ichnotaxon Oichnus ovalis for these oval drill holes attributed to octopods.…”

“…The radular teeth may be used to remove the organic component of the shell, while the saliva removes the calcium carbonate (Runham et al, 1997). These glands also provide the fluids that relax the muscles of the prey injected after the completion of the drill hole (e.g., Nixon and Maconnachie, 1988). Unlike gastropods that drill, Nixon and Maconnachie (1988) found that the properties of mollusk shells determine the size, shape, and form of the octopod drill hole, and not the size of the predator or the mouth parts of Octopus vulgaris.…”

Distribution, growth rate, and death from octopod and gastropod predation ofTawera bollonsi(Bivalvia: Veneridae) at the Auckland Islands

“…This shape is partly a reflection of the shell structure and sculpture. Cavities drilled by different individual octopus in shells of one prey species have been shown to be more similar than those drilled by one individual octopus in different species of prey (Nixon & Maconnachie 1988). The prey shell structure is important in determining the shape and character of the hole, rather than the size of the predator.…”

Exploitation patterns of <i>Octopus vulgaris</i> in two Mediterranean areas

“…Despite its importance, there is a lack of analytical studies incorporating the multigear approach needed for the evaluation of multigear fisheries. Most of the studies published on the biology of O. vulgaris in the Mediterranean refer to individuals kept in laboratory conditions (Boucaud-Camou et al, 1976;Nixon and Maconnachie, 1988;Villanueva, 1995;Villanueva et al, 1996). A limited number of reports deal with the exploitation of this species by trawls in the Western Mediterranean (Sánchez and Martín, 1993;Quetglas et al, 1998;Sartor et al, 1998).…”