Feeding Preferences of a Generalist Salt-Marsh Crab: Relative Importance of Multiple Plant Traits

Abstract

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Plant defences and the role of epibiosis in mediating within-plant feeding choices of seagrass consumers

“…Our results strengthen the findings from a previous study which showed that leaf structural defences are the primary factor in determining the feeding choices of P. lividus between inflorescences and leaves, whereas nutrient content and secondary chemistry are of secondary importance (Vergés et al 2007b). These findings concur with numerous studies that show structural defences to be of paramount importance in mediating the feeding preferences of a wide range of terrestrial and aquatic herbivores (Coley 1983;Pennings et al 1998;Lucas et al 2000;Hanley et al 2007). …”

Environmental gradients and herbivore feeding preferences in coastal salt marshes

“…Plants experiencing salt stress commonly increase tissue concentrations of salts and/or nitrogen-based osmotica (Flowers et al 1977(Flowers et al , 1986Rozema et al 1985). Salt in food stimulates feeding by Armases (Pennings et al 1998), likely explaining the preference of this crab for plants from the high end of the salinity gradient. Most herbivores would be expected to prefer foods with higher nitrogen content (White 1984), but this may have been partially counterbalanced in the case of insects by higher salt levels and/or by other changes in plants growing in high-salinity soils.…”

Utilization of invasive tamarisk by salt marsh consumers

“…Litter quality C:N ratios of plants have been utilized as measures of litter quality (Sterner and Elser 2002;Pennings et al 1998). To measure C and N content, fresh leaf material from nonsenescent tamarisk and several native plants (S. pacifica, Juncus acutus, J. cornosa) in each block (n = 4) was collected from the study site, rinsed with Milli-Q Ò water, placed in pre-combusted vials or tin boats, dried at 65°C, and kept in a desiccator until analysis.…”