Richard J. Howells, Sarah J. Burthe, Jon A. Green, Michael P. Harris, Mark A. Newell, Adam Butler, David G. Johns, Edward J. Carnell, Sarah Wanless, Francis Daunt, 2017. From days to decades: short- and long-term variation in environmental conditions affect offspring diet composition of a marine top predator. Marine Ecology Progress Series. doi.org/10.3354/meps12343.
Climate change is altering long-term mean environmental conditions, such as temperature, and increasing short-term climatic variability, such as weather. Populations will be affected by both, but studies tend to focus on just one scale. The North Sea is one of the most rapidly warming marine ecosystems on the planet, and so is a useful system in which to test these impacts. Here we test the effects of both long- and short-term environmental change on the diet composition of a marine top predator, the European shag Phalacrocorax aristotelis at a North Sea colony over 3 decades. We identified a dramatic dietary change, from a diet dominated by lesser sandeel Ammodytes marinus in the 1980s to an increasingly diverse range of prey in recent years. Over the same period the size of sandeel also reduced. Dietary diversity was linked to ocean warming, while the proportion of sandeel in the diet was lower on windy days. Thus, predicted changes in climate means and variability may have important implications for diet composition of European shags in the future.
See also: BBC news article
Bjerke, J. W., Treharne, R., Vikhamar-Schuler, D., Karlsen, S. R., Ravolainen, V., Bokhorst, S., Phoenix, G. K., Bochenek, Z., Tømmervik, H., 2017. Understanding the drivers of extensive plant damage in boreal and Arctic ecosystems: Insights from field surveys in the aftermath of damage. Science of the Total Environment. doi.org/10.1016/j.scitotenv.2017.05.050.
The exact cause of population dieback in nature is often challenging to identify retrospectively. Plant research in northern regions has in recent decades been largely focused on the opposite trend, namely increasing populations and higher productivity. However, a recent unexpected decline in remotely-sensed estimates of terrestrial Arctic primary productivity suggests that warmer northern lands do not necessarily result in higher productivity. As large-scale plant dieback may become more frequent at high northern latitudes with increasing frequency of extreme events, understanding the drivers of plant dieback is especially urgent. Here, we report on recent extensive damage to dominant, short, perennial heath and tundra plant populations in boreal and Arctic Norway, and assess the potential drivers of this damage.
Rebecca A. Senior, Jane K. Hill, Suzan Benedick, David P. Edwards, 2017. Tropical forests are thermally buffered despite intensive selective logging. Global Change Biology. doi.org/
Selectively logged forests harbour much of the world’s remaining terrestrial biodiversity, but we do not yet know whether this can be maintained under future climate change. One mechanism by which organisms can avoid suboptimal temperatures is by exploiting cooler ‘microclimates’ (climate at spatial scale of mm-m). We used thermal imaging cameras and dataloggers to compare the temperature and availability of cool understorey microclimates in undisturbed primary forest and intensively logged forest on Borneo. Despite major differences in forest structure, thermal buffering potential was comparable between logged and primary forests. As such, the ability of temperature-sensitive understorey species to persist in logged forests under climate change will not be limited by their ability to find and utilise cool microclimates. Selectively logged forests can play a crucial role in the long-term maintenance of global biodiversity.
Rebecca A. Senior, Jane K. Hill, Pamela González del Pliego, Laurel K. Goode, David P. Edwards, 2017. A pantropical analysis of the impacts of forest degradation and conversion on local temperature. Ecology and Evolution.
Temperature has a huge influence on species’ ecology. Loss and degradation of tropical forest changes vegetation structure, which is a key determinant of temperature at the scale at which most organisms actually experience the world (mm to ha). Using data from the literature, we assessed the impact of land-use change on local temperature across the tropics. We found that conversion from forest to agriculture increased temperature by anything up to 13.6°C, but the effect was mitigated below-ground and was not found in forests degraded by activities such as logging. Land-use change can therefore have a huge warming effect even before factors such as droughts and climate change are considered, but certain habitats – such as below-ground and in degraded forests – may be able to protect species from such change.