Open source intelligence (OSINT) reveals that Marine Mammal pens were present at the Russian Navy’s base in Tartus, Syria, for a period in 2018. The deployment does not appear to have been reported previously. The mammals were likely part of anti-diver defenses at the base, which is the a crucial logistics hub for Russian forces operating in the country.
Two rectangular pens are clearly visible on commercial satellite imagery between September and December 2018. Based on the size of the pens the mammals involved were most likely seals. Dolphin pens are normally larger and octagonal in shape. The same goes for the Beluga whales used in colder waters such as the one which found itself in Norway in April 2019. The Russian Navy is known to train seals for anti-diver missions, but exact details of the current inventory of marine mammals is unclear.
There is a lot for Russia to protect in Tartus. It is their only naval base in Syria and more generally, the Mediterranean. Virtually all of the Bosporus Express traffic of arms and equipment is heading there. And it is the home port of the permanent Mediterranean squadron, known as the 5th Operational Squadron. This has warships and even submarines, although their deployment there is complicated by the Montreux Convention which was intended, in part, to stop submarines being deployed between the Black Sea and Mediterranean. This hasn’t stopped Russia deploying its Black Sea Fleet subs to Tartus however.
The exact location of the pens, on the end of the main military quay, is actually a spot within the Syrian Navy’s area. However the berths there are generally used by Russian forces and the pens were flanked by Russian naval vessels. So combined with what is known of Russia’s marine mammal program infrastructure, there seems little doubt that it was a Russian deployment.
It is not clear why the mammal deployment only lasted a few months. Possibly their mission may have been specific or of a fixed duration. Or maybe it was experimental, to build up the Russian Navy’s resurgent marine mammal program’s capabilities. Or the deployment was not considered a success and was abandoned.