Testing biodegradable interventions to disrupt plant–animal feedbacks and promote seagrass establishment

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Biogeochemical and physical feedbacks are well known to prevent ecosystem recovery even after initial disturbance factors are mitigated. However, multi‐trophic interactions that may maintain disturbed areas have received less attention, despite their potential importance in mediating restoration success. In this study, we surveyed stingray feeding pits and ghost shrimp burrows to explore the potential role of these predator–prey disturbance agents in maintaining denuded areas within seagrasses, and experimentally excluded stingrays with a low‐cost, biodegradable restoration approach—bamboo stakes—to test if limiting predator access could facilitate seagrass recovery. The multi‐site survey revealed high densities of ray pits (approximately 0.9 m −2 ) and ghost shrimp burrows (>60 m −2 ) in bare and seagrass meadow edge areas, and zero to low ray pit and shrimp burrow densities (<0.01 and <28 m −2 , respectively) in areas with seagrass cover above 50%. Over 12 months, the experiment using bamboo stakes—deployed in either a grid or perimeter formation at the center and seagrass‐adjacent edge of bare patches at two sites, where both bioturbators were present—revealed that both bamboo formations reduced ray pits and facilitated seagrass establishment. However, the newly established seagrass became buried by ghost shrimp bioturbation, which drove sediment deposition rates of approximately 10 cm per year. Even along the seagrass edge where seagrass could recover via rhizome expansion, our observations suggest that seagrass colonization was limited by burial. Together, these results suggest that layered approaches to interrupting both trophic and bioturbation interactions may be necessary to reestablish seagrass when multiple inhibitory processes are present.