The growth rate of the Muslim population is in decline - from 3.8% in 2000 to 2.4% in 2014. Despite this, the Muslim population is still growing faster than any other in Israel - with the Jewish growth rate at 1.9%, Christian at 1.6%, and Druze at 1.5%.
Israel is one of many countries in the world today where the Muslim birthrate is in decline. This is a global trend. It runs completely contrary to the apocalyptic fantasy of Muslims outbreeding every other religion and taking over the whole world.