Preliminary observations on factors affecting foraging activity in the limpet Patella vulgata

Abstract

Activity patterns of limpets were studied at two adjacent sites in an Irish sea lough, Lough Hyne, in order to relate timing of activity to physical and biological influences. Activity was suppressed during heavy rainfall, and osmotic stress from dilution appears to have led to increased mortality in transplanted limpets. Activity increased as tides progressed from neaps to springs, and for limpets low on the shore it was enhanced by wave action. It is suggested that lack of activity in calm water may reduce predation pressure from crabs, which caused high mortality in transplanted limpets. Either low relative humidity or dryness of the rock diminished activity of low-water limpets. Differences in feeding activity between low-water limpets and high-water limpets may relate to food supply, since more food was available low on the shore, and the guts of low-water limpets contained more diatoms than those of high-water individuals. Differences between the two sites are at present unexplained but may relate to differences in micro habitats.

Macroalgae contribute to the diet of Patella vulgata from contrasting conditions of latitude and wave exposure in the UK

“…These indirect studies have led to the conclusion that P. vulgata is a keystone species in the intertidal, preventing macroalgal growth through microphagous grazing of epilithic biofilm and associated macroalgal propagules (spores and germlings) (Hill & Hawkins 1991, Jenkins & Hartnoll 2001, Jenkins et al 2005, Coleman et al 2006, Jonsson et al 2006, Moore et al 2007). This view is supported by observational studies of limpet foraging behaviour (Hartnoll & Wright 1977, Little et al 1988, Della Santina et al 1994) and several studies which directly examined limpet gut contents (Hawkins et al 1989, Little et al 1990, Hill & Hawkins 1991.…”

European-scale analysis of seasonal variability in limpet grazing activity and microalgal abundance

“…Error bars = ±1 SE temporal scales than is possible with more conventional techniques of direct observation (e.g. Hartnoll & Wright 1977, Little et al 1990 or those techniques requiring sophisticated recording equipment (e.g. Della Santina et al 1994).…”

Foraging in the limpet Patella vulgata: the influence of rock slope on the timing of activity

“…Animals were scored as active if the Tipp-Ex TM number on the home scar and the shell did not align. The survey was initially conducted on 5 September 1992 (at mean neap tides) and repeated on 11 September (neap^spring tides) and on 15 September (mean spring tides), at which times some of the readings (for sites at East Island and Boundary Bay) were taken from automatic recording devices (as used by Little et al, 1991;N23).…”