The rapid climate change we are experiencing today poses a major threat to earth’s biodiversity and ecosystem functions. Climate change is expressed in overall warming, increase in the frequency of extreme weather events (for example heat waves or intensifying storms), and in the oceans also sea level rise and acidification.  The biota in Levant Basin (the eastern part of the Eastern Mediterranean) is potentially one the most sensitive marine regions to climate change. This is because the Levant is the southeastern edge (trailing) of distribution of most Mediterranean and Atlanto-Mediterranean species. The coastal water conditions are naturally extreme, being the hottest, saltiest, and having the lowest primary productivity in the Mediterranean. The temperature range of sea surface temperature (SST) on the Israeli coast (at the southeastern corner of the Levant basin) in the 1970-90 was about 15-29 °C. However, satellite data analysis suggested an increase of almost 1oC in the eastern Mediterranean SST between 1985-2006 (re analyzed from http://www.coastalwarming.com). More recent analysis of temperatures measured in-situ >50 kms offshore the Israeli coast, suggested a 3°C SST warming between 1980-2013. In such naturally-extreme environment that is becoming more extreme, native species may be more vulnerable to stress, which can trigger population collapses and possibly extirpations. On the other hand, warming can be an advantage for warm-loving alien species, such as those invading from the Red Sea through the Suez Canal.