The MBA MarClim® time-series has just been published by MBA's Nova Mieszkowska and the MarClim team in the scientific journal Global Change Biology. The time-series tracks shift in the range of species in response to climate change, and discovered intertidal invertebrates are showing some of the fastest responses of animals in any natural system.
The MarClim® project time-series data contributes to national monitoring, and has the most spatio-temporally extensive time-series for rocky intertidal organisams globally. Data stretches back to the 1950s for native species of macroalgae and invertberates that have a range of thermal evolutionary origins. Annual surveys are carried out at over 100 sites around the UK coastline, including locations beyond the current range-edges of species, to ensure detection of any future shifts in species biogeographic distributions. The MarClim project builds and strengthens links between the policy, science, conservation and climate change communities. This enables effective networking and strong linkages to be made during the MarClim work across all areas, and enhances the value and ownership of the end products and conclusions.
Changes in rocky shore community composition as responses to climatic fluctuations and anthropogenic warming can be shown by changes in average species thermal affinities. In this study, we derived thermal affinities for European Atlantic rocky intertidal species by matching their known distributions to patterns in average annual sea surface temperature. Average thermal affinities (the Community Temperature Index, CTI) tracked patterns in sea surface temperature from Portugal to Norway, but CTI for communities of macroalgae and plant species changed less than those composed of animal species. This reduced response was in line with the expectation that communities with a smaller range of thermal affinities among species would change less in composition along thermal gradients and over time. Local-scale patterns in CTI over wave exposure gradients suggested that canopy macroalgae allow species with ranges centred in cooler than local temperatures (‘cold-affinity’) to persist in otherwise too-warm conditions. In annual surveys of rocky shores, communities of animal species in Shetland showed a shift in dominance towards warm-affinity species (‘thermophilization’) with local warming from 1980 to 2018 but the community of plant and macroalgal species did not. From 2002 to 2018, communities in southwest Britain showed the reverse trend in CTI: declining average thermal affinities over a period of modest temperature decline. Despite the cooling, trends in species abundance were in line with the general mechanism of direction and magnitude of long-term trends depending on the difference between species thermal affinities and local temperatures. Cold-affinity species increased during cooling and warm-affinity ones decreased. The consistency of responses across different communities and with general expectations based on species thermal characteristics suggests strong predictive accuracy of responses of community composition to anthropogenic warming.
Mieszkowska lab website www.mba.ac.uk/fellows/nova