Mass Mortality of Foundation Species on Rocky Shores: Testing a Methodology for a Continental Monitoring Program

Abstract

Global concern around substantial losses of biodiversity has led to the development of a number of monitoring programs. Networks were established to obtain appropriate data on the spatial and temporal variation of marine species on rocky shores. Recently, the Marine Biodiversity Observation Network Pole to Pole of the Americas (MBON P2P) program was established and is coordinating biodiversity surveys along coastal areas throughout the continent. The goal of this paper was to test the usefulness and adequacy of a methodology proposed for the MBON P2P program. Changes in benthic assemblage cover were studied on monitored sites in northern Patagonia before and after the 2019 austral summer. Long-term dynamics of mussel bed is described based on existing data. Results showed that assemblages before the 2019 austral summer were different from assemblages after it. Thus, a mussel mass mortality event could be detected with this methodology. It took less than a year for mussel cover to drop from 90 to almost 0%; even where substantial changes in mussel bed cover were not registered in the previous ~20 years at the study area. This simple methodology is an adequate tool for monitoring rocky intertidal habitats. Yearly monitoring is needed, as a minimum, to perceive this kind of process timely. Real-time detection offers the opportunity of properly understanding the causes that lead to the loss of key community components, such as these foundation species. Furthermore, it would provide early warning to decision-makers enhancing the chances of conservation of natural environments and their ecosystem services.

Changes in the composition of invertebrate assemblages from wave-exposed intertidal mussel stands along the Nova Scotia coast, Canada

“…Therefore, mussels are particularly relevant for the ecology of the coastal environments they inhabit. Intertidal stands of mussels, however, are increasingly being lost in relation to the ongoing climatic and oceanographic change ( Sorte et al, 2017 ; Seuront et al, 2019 ; Mendez et al, 2021 ; Fields & Silbiger, 2022 ; Raymond et al, 2022 ; Cameron & Scrosati, 2023 ; Scrosati, 2023 ). This is, in fact, a trend seen also in other marine foundation species such as corals, seaweeds, seagrasses, salt marsh plants, mangroves, and other bivalves ( Wernberg et al, 2024 ).…”

Robots Versus Humans: Automated Annotation Accurately Quantifies Essential Ocean Variables of Rocky Intertidal Functional Groups and Habitat State

“…Intertidal invertebrates and algae are exposed to extreme weather and climate variability with large fluctuations in temperature, salinity, and water availability (Madeira et al, 2012). Mass mortality events have been reported from intertidal sites across the globe (e.g., Harley, 2008;Mendez et al, 2021), and the incidence of marine heat waves is increasing (Hobday et al, 2016). It is not clear yet what the potential consequences of these mortality events are for patterns of species distribution, biodiversity, and ecosystem services (Román et al, 2020;Vye et al, 2020).…”

Application of a Simple, Low-Cost, Low-Tech Method to Monitor Intertidal Rocky Shore Assemblages on a Broad Geographic Scale

“…Communities within these habitats are exposed to particularly harsh environmental conditions that lead to adaptations of the local species (Bertness et al, 2006). In addition, a range of anthropogenic threats may add stress to communities and lead to changes in cover of dominant space occupiers (Mendez et al, 2017(Mendez et al, , 2021Sorte et al, 2017).…”