Saving the Killifish of the Adhari Pool in Bahrain
Wednesday 20 April 2005
In late January we received an urgent email from a biologist in Germany asking if we could save a population of Arabian killifish held at HM Customs at Heathrow.
The Arabian Killifish, Aphanius dispar, were due to be sent to Belgium from Bahrain but unfortunately the Belgian authorities would not allow them entry. The fish had been transferred to a local aquatic shop for temporary holding but the shop needed to move them out quickly as they were taking up space.
On the 21 January ZSL staff retrieved the fish and brought them back to our aquarium where they were acclimated to one of our holding tanks. The next several days were spent researching the species' water quality requirements and gathering information about the habitat they came from. During our investigation we discovered a number of fascinating facts not only about the Arabian killifish but also about the particular group that we now held.
The Arabian killifish is a fairly widespread species that occurs from Egypt and Somalia east to Western India. They have an amazing tolerance for desert extremes and can survive in temperatures that range from as low as 10 degrees C in winter to well over 40 degrees C in summer. Some populations live in pure freshwater, others in marine water and still others in hyper saline water. There is even a population living in the Dead Sea.
The population at London Zoo came from a small oasis in Bahrain called the Adhari Pool. This pool was a very popular swimming area with local people for many years. Early traveller's accounts suggest the pool was once used as a watering hole for camels and its waters were crystal clear and warm year round. Thousands of Arabian killifish formed shoals that would surround swimmers when they entered the pool to cool off.
Unfortunately today the Adhari Pool has been altered extensively. The pool has been modernised for swimming and is now used by locals for washing their cars, the detergents running back into the pool. The water levels in the pool are now dropping from excessive use and the remaining water is virtually unsuitable for fish. Concerned biologists decided to capture as many of the remaining killifish to try and save them from certain death. The last 200 fish were caught in a murky drainage channel near a road underpass. Half of the fish went to the Bahrain Aqualife Centre and the other half due to go to Belgium to provide a back up population in case of catastrophe. These are the fish we now hold.
Since arriving we have learned lots about the Arabian killifish. The knowledge gained has enabled us to breed the species already and we now have many fry. Hopefully the Belgian authorities will allow the biologists working with the species to bring them into Belgium. In the meantime, London Zoo will continue to hold, breed and study these fascinating fish. Meanwhile back in Bahrain, biologists are busy looking for a suitable alternative habitat to the Adhari Pool so that the Arabian killifish can be returned to the wild.
article by Brian Zimmerman