"Two major processes are threatening the integrity of marine ecosystems: climate change and bioinvasions. Both are of extreme importance to the Levant shores because the region (1) has extreme biophysical conditions, being the hottest, saltiest and most nutrient-poor area in the Mediterranean—and warming may cause regional extinctions; and (2) is a hotspot of marine biological invasions, mostly IndoPacific species that flooded through the Suez Canal. Another local threat is the diminishing of its rocky intertidal ecosystem engineers, vermetid snails, that protect the biogeographically-distinctive intertidal reefs from erosion. Vermetid decrease many mean the deterioration of the ecosystem they form. The threats of climate change, bioinvasions and loss of ecosystem engineers all point to the need of a research program that will monitor the ecological community and biodiversity patterns along the coast at multiple scales and follow their changes over time, together with field and laboratory experiments that will enhance the predictive power of models that forecast future changes in the ecology of the system. This proposal aims to study several ecological aspects of the rocky intertidal along one of the most unique and ecologically-dynamic coasts, and investigate the effects of climate change and bioinvasions in the context of community ecology. Objectives: (1) to launch a long-term monitoring program of community biodiversity along the Israeli coast to enable the detection of long-term changes related to global warming, bioinvasions and other potential influences, (2) to use natural heat-stress events as proxies for the potential effects of extreme climate change events, (3) to test the response of important species to elevated temperatures and CO2, and (4) to study recruitment patterns of influential invasive species and experimentally test their biological interactions with indigenous species and other invaders and their general impacts on biodiversity."