Recognizing cephalopod boreholes in shells and the northward spread of Octopus vulgaris Cuvier, 1797 (Cephalopoda, Octopodoidea)
Auke-Florian HIEMSTRA 2015 full article.
This article is particularly interesting because it notes that drilling may NOT be solely by the radula.
Auke-Florian HIEMSTRA 2015 full article.
INTRODUCTION Aristotle was the first to observe octopuses feed on molluscs (see D’Arcy Thompson, 1910), but it was Fujita who discovered in 1916 that a hole was bored in the shell of cultured pearl oysters prior to its owner being eaten; a behaviour independently discovered by Pilson & Taylor (1961) in laboratory tanks. Octopuses are versatile carnivores with a diverse array of prey, ranging from soft bodied to heavily armoured organisms, such as bivalves, gastropods and crustacean (Nixon, 1987). There are different techniques of penetrating a shell to gain the meat inside (Steer & Semmens, 2003). Enteroctopus dofleini (Wülker, 1910), for example, has four techniques of getting into a clam. If possible, they use the easiest way, according to the optimal foraging model, resorting to drilling only when other methods are unsuccessful (Mather & Anderson, 2007). Regardless of their prey size, Octopus will always try the pulling method first (Fiorito & Gherardi, 1999), but if unsuccessful, it changes its tactics and initiates a drilling response (Hartwick et al., 1978). ...
This article is particularly interesting because it notes that drilling may NOT be solely by the radula.
The drilling activities seem to be carried out by another structure within the buccal mass, namely the small conical teeth on the tip of the muscular salivary papilla (Nixon, 1979a), as not one out of ten octopuses drilled again after surgical removal of their salivary papilla (Nixon 1979a; 1979b). Since the discovery of octopus drillings there has been speculation about possible chemical action on the shell (Fujita, 1916; Pilson & Taylor, 1961; Arnold & Arnold, 1969; Wodinsky 1969; 1973). After comparison of the shell surface it was indeed concluded that some chemical dissolution during drilling may occur (Nixon et al., 1980; Ambrose, 1988).