Long‐term declines in an intertidal foundation species parallel shifts in community composition

• DOI: 10.1111/gcb.13425
• Publication Date: 2016-07-13T16:30:32Z
• Authors: Cascade J. B. Sorte; Victoria E. Davidson; Marcus C. Franklin; Kylla M. Benes; Meredith M. Doellman; Ron J. Etter; Robyn E. Hannigan; Jane Lubchenco; Bruce A. Menge
• Keywords: Foundation (evidence); Foundation species

Abstract The earth is in the midst of a biodiversity crisis, and projections indicate continuing accelerating rates global changes. Future alterations communities ecosystems may be precipitated by changes abundance strongly interacting species, whose disappearance can lead to profound other including an increase extinction rate for some. Nearshore coastal are often dependent on habitat food resources provided foundational plant (e.g., kelp) animal shellfish) species. We quantified blue mussel ( M ytilus edulis ), foundation species known influence diversity productivity intertidal habitats, over past 40 years Gulf Maine, USA , one fastest warming regions ocean. Using consistent survey methods, we compared contemporary population sizes historical data from sites spanning >400 km. results these comparisons showed that mussels have declined Maine >60% (range: 29–100%) at site level since earliest benchmarks 1970s. At same time as declined, community composition shifted: four with data, sessile became increasingly algal dominated. Contemporary (2013–2014) surveys across 20 richness was positively correlated mid high zones. These suggest declines critical already impacted community. To inform future conservation efforts, provide database baselines dynamics Maine. Our underscore importance anticipating not only but also identity component strong interactors like potential drive cascading shifts.