Vladimir Putin's war chest reportedly includes a unit of military dolphins trained to attack enemy divers.
The Russian President's war efforts were rocked on Saturday when a section of the Kerch Bridge - which links Russia with Crimea - was blown to bits in a suspected Ukrainian attack.
Speculation over the mode of attack has been feverish, with some suggesting a covert operation by a specialised team in the Ukrainian military and others raising the possibility of a long-range missile.
The Kerch bridge was guarded on all fronts with missile defence systems, fighter jets, warships, military divers and heavy artillery.
But one small detail spotted in the dramatic footage of the blast has brought the role of Russia's military dolphins back into sharp focus.
In one CCTV clip, a small wave appeared to roll under the bridge just before the explosives were detonated, fuelling speculation about the possibility of Ukrainian special forces using a boat or water-based drone to launch the attack.
This is exactly the type of attack that the navy dolphins have allegedly been trained to intercept, with reports that the mammals are patrolling the waters across the Azov and Black Sea ready to hunt down enemy frogmen.
While their deployment during the Ukraine conflict is unconfirmed, further speculation over the use of the mammals arose when satellite images showed two dolphin pens were moved to Russia's Sevastopol harbour naval base - which sits on the southern tip of Crimea - in February of this year.
Russia has a history of training dolphins for defence purposes including the clearance of underwater mines and the protection of military sites and ships from the threat of covert enemy divers. The Russian government first started exploring the military uses of marine mammals at the Sevastopol naval base during the Soviet era.
The US and Russia developed the use of military dolphins during the Cold War, harnessing their echolocation capabilities to detect underwater objects such as mines.
More recently, satellite imagery captured in 2018 revealed that Russia was using dolphins at its naval base in Tartus, Syria during the Syrian civil conflict. The US is reported to have spent almost $30m maintaining its own battalion of military dolphins.
Before Russia's invasion of Ukraine in February this year, Gervase Phillips, a lecturer in history, politics and philosophy at Manchester Metropolitan University, told Forces News: "We have nothing like a dog's nose to smell explosives yet and nothing as good at finding things on the seabed as a dolphin or a sea lion.
"There are all kinds of those military roles for which, unfortunately, we have no practical alternative."
The US Navy began its marine mammal programme in 1960, originally hoping to both improve the hydrodynamics of its torpedoes, and its ability to detect objects under water, by studying dolphins.
Ukraine has not yet taken official responsibility for the attack on the Kerch Bridge, with a top aide to President Zelensky quipping that "Putin should be happy. Not everyone gets such an expensive birthday present".
Later on Saturday, the Russian government posted footage of traffic travelling across the bridge following a hasty repair operation.
