Future ocean climate homogenizes communities across habitats through diversity loss and rise of generalist species

Abstract

Rising anthropogenic CO 2 levels and the consequent increase in temperature and acidification of the ocean is impacting biodiversity and will change ecosystems in ways that are still difficult to forecast. Understanding the consequences of climate change and mitigating its impacts are urgent priorities for the conservation and management of species and human societies (Doney et al., 2012; Nagelkerken & Connell, 2015). Increases in CO 2 levels and temperature of seawater may affect ecological processes directly by increasing carbonate solubility and impairing animal behavior, and indirectly through changes in food availability, predator densities, or competitive hierarchies

Temperature increase and its effects on fish stress physiology in the context of global warming

“…It is difficult to generalize about the vulnerability of fishes to global warming since their response will depend on multiple factors, including their natural distribution, their intrinsic metabolic capacities and their life history or genetic background (Colossi Brustolin et al ., 2019; Comte & Olden, 2017; Somero, 2010). In addition, fish species or individuals differ considerably in the magnitude of their responses to specific stressors (Barton, 2002; Mommsen et al ., 1999), including increased temperature (LeBlanc et al ., 2012; Madeira et al ., 2013).…”

Identifying “vital attributes” for assessing disturbance–recovery potential of seafloor communities

“…Since the Baltic seafloor is a naturally low-diversity system, it might be envisioned as a proxy for a future world, where current trajectories of biodiversity loss predict increases in biotic homogenization and fragmentation across landscapes (Blowes et al, 2019;Brustolin et al, 2019 Here, dispersion in the recovery trait space (FDis I ) was related to variability in initial recovery among sites, where high FDis I was related to slower initial recovery. This constrained number of outcomes likely decreases the recovery and adaptive potential of this system in the long term and in the face of disturbances that alter the environmental conditions (e.g., climate change).…”

Ocean acidification boosts reproduction in fish via indirect effects

“…Increased primary productivity and primary producer biomass under ocean acidification enhances food availability to both vertebrate and invertebrate herbivores [29,30], whose increased abundances and productivity fuel abundances at higher trophic levels [31]. While increased productivity is frequently observed at multiple food web levels, studies suggest that generalists, or "weedy" species, benefit most from this resource increase due to their life history characteristics, including wide and flexible trophic and habitat niches [32,33]. This allows generalists to quickly adapt to a changing environment to the detriment of more specialist species.…”