Grazers as consumers and recyclers

Recent work in the Bracken Lab highlights the top-down (i.e., consumptive) and bottom-up (i.e., recycling) roles that grazers play in intertidal systems and shows how community composition mediates the relative importance of grazers’ top-down and bottom-up roles (Bracken et al. in press). Using a classic grazer-seaweed system on New England rocky shores, we show that grazers not only consume seaweeds but also benefit them by recycling nitrogen. Importantly, the roles of grazers as consumers versus recyclers change depending on which seaweed species are present. This work was published online this week in the journal Ecology.