Traits affecting nutrient recycling by mobile consumers can explain coexistence and spatially heterogeneous trophic regulation across a meta‐ecosystem

Abstract

Ecosystems are linked through spatial flows of organisms and nutrients that impact their biodiversity and regulation. Theory has predominantly studied passive nutrient flows that occur independently of organism movement. Mobile organisms, however, commonly drive nutrient flows across ecosystems through nutrient recycling. Using a meta‐ecosystem model where consumers move between ecosystems, we study how consumer recycling and traits related to feeding and sheltering preferences affect species diversity and trophic regulation. We show local effects of recycling can cascade across space, yielding spatially heterogeneous top‐down and bottom‐up effects. Consumer traits impact the direction and magnitude of these effects by enabling recycling to favour a single ecosystem. Recycling further modifies outcomes of competition between consumer species by creating a positive feedback on the production of one competitor. Our findings suggest spatial interactions between feeding and recycling activities of organisms are key to predicting biodiversity and ecosystem functioning across spatial scales.

The significance of partial migration for food web and ecosystem dynamics

“…Further, Gounand et al (2014) predicted dispersal can stabilise nutrient‐enriched meta‐ecosystems by redistributing excess nutrients to unfertile ecosystems, but that this is dependent on intermediate rates of dispersal. Studies of feeding movements have documented their potential to have trophic and ecosystem‐level effects, including driving trophic cascades (García‐Callejas et al, 2019), having top‐down impacts that stabilise consumer populations (McCann et al, 2005) and influencing nutrient cycles, which in turn can drive primary productivity (Vanni, 2002) and have implications for species coexistence (Peller et al, 2022). Yet, few studies have explicitly considered how the partial nature of feeding movements mediates these effects.…”

“…Dispersal and feeding movements can also influence ecosystem dynamics (e.g. Gounand et al, 2014; Peller et al, 2022) and be influenced by ecosystem dynamics (Fronhofer et al, 2018; Heckmann et al, 2012). The feedbacks between movement propensity and ecosystem dynamics we describe may, therefore, be common for all movement types.…”

“…To develop a mechanistic understanding, we suggest metacommunity and meta‐ecosystem models (e.g. Guzman et al, 2019; Leroux & Loreau, 2012; Peller et al, 2022) will be a key tool as they allow (1) a simplified, yet explicit representation of trophic and ecosystem dynamics in resident and migratory ecosystems, (2) interactions and feedbacks between ecosystems via movement and (3) the consideration of eco‐evolutionary dynamics. In addition, applying network theory could reveal great insights on how partial migration influences the structure of trophic interactions across migration cycles and the implications for food web and ecosystem properties, such as stability (e.g.…”

“…For instance, theoretical investigations into the effect of non‐dispersal movements often assume it is a property shared equally by all individuals of a population (e.g. Holdo et al, 2011; Peller et al, 2022).…”

Linking animal behavior to ecosystem change in disturbed environments

“…10.3389/fevo.2022 The transfer of energy and matter between habitats and ecosystems is obviously also sensitive to changes in animal movements. Shifts in where animals stay, what they feed on, and where they die, alter biogeochemical processes within habitats and, thus, ecological processes and components, such as primary production and biodiversity (Peller et al, 2022).…”