Shell Damage Patterns in Limpkin Mussel Middens at Bois d’Arc Lake, Arkansas

Abstract

The Limpkin (Aramus guarauna) is rapidly colonizing the lower Mississippi Valley from recently established Gulf Coast populations. Anecdotal reports indicate that it feeds on freshwater mussels and gastropods in Arkansas, but without documentation. Here I report an analysis of Limpkin shell middens from Bois d’Arc Lake in Hempstead Co. Limpkins at this location preyed heavily on Pyganodon grandis (Giant Floater), a large mussel species widely distributed in the Mississippi Valley. Limpkins employ vigorous bill blows to pierce holes in mussels and usually attack the anterior end of the shell. Video and photographs of feeding birds provide new insight on the mechanics of shell opening and tissue extraction. Given the distribution and current populations of mussels in Arkansas, Limpkins have the potential to become regular summer residents in the mussel-rich areas of the state.