Some species of fish, amphibians and snails live in these small pools/cavities next to the Dead Sea - these small pools/cavities are fed by underground fresh water springs. None of the animals living in these pools could survive in the Dead Sea. The cavities of these small pools are caused by incoming fresh water (that follows the receding Dead Sea waters) dissolving salt layers just beneath the surface of the Dead Sea banks The number of sink holes/cavities in the Dead Sea region is around 3000, mostly along the Israeli border of the Dead Sea. The sinkholes also exist on the Jordanian border of the Dead sea.
The Dead Sea has been shrinking in size. Example: Twenty-five years ago a spa was built at Ein Gedi on the shore of the Dead Sea. Now that spa is a one-mile trolley ride from the Dead Sea. Why is it shrinking? A major source of water for the Dead Sea is the Jordan River (and therefore the Sea of Galilee) – water has been diverted from the Jordan River by Israel, Syria and Jordan for drinking and irrigation. In the 1960s, Israel and Jordan built plants to divert water from the Jordan River - since the 1960's, the Dead Sea has shrunk by a third of its size. Also, there is little rainfall in this desert area. The shrinking of the Dead Sea and the sinkhole phenomenon described above have been exacerbated by chemical and tourism related activities.
One reason the Dead Sea is salt-rich is that there is no way for water to flow out of it – so, evaporation leaves it salt-rich. The water is so mineral laden that it is around 26% solid. The therapeutic effects and beauty enhancements of the minerals and black mud from the Dead Sea have been touted since ancient times. We saw several people come out of the Dead Sea covered with its black mud. Judy bought some mineral products from the Dead Sea in Tel Aviv - the company's name is Ahava - we saw their factory next to the Dead Sea.
The Dead Sea - lowest point on earth – about 1,300 feet below sea level. It is considered "dead" because its high salinity prevents macroscopic organisms, such as fish and aquatic plants, from living in it. However, bacteria, microbial fungi and one type of algae live in it.
From the Hebrew Bible: The Dead Sea was a place of refuge for King David. King David was said to have hidden from Saul at Ein Gedi on the shore of the Dead Sea. Also, on the shore of the Dead Sea would have been the cities mentioned in the Book of Genesis which supposedly were destroyed during the time of Abraham: Sodom and Gomorra and the three other "Cities of the Plain" - Admah, Zeboim and Zoar.