Russia added new anti-maritime drones defenses across the inner harbor in Sevastopol. The defensive booms are expected to stops Ukrainian USVs
A satellite image appeared on the network showing water area of temporarily occupied Sevastopol (Crimea) where ships and submarines of the russian Black Sea Fleet are based.
The russian Navy added a new defensive boom which is supposed to protect the area from uncrewed surface vessels (USV). Moreover, there is always at least one Project 22160 patrol ship with the Tor surface-to-air missile system (SAM) on the helipad in the harbor. It was reported by H I Sutton.
The russian Black Sea Fleet defense is being regularly upgraded because of the Ukrainian maritime drones that pose a severe threat to it. For instance, Project 636 Varshavyanka class submarine which carries the 3M-54 Kalibr cruise missiles left the port in the end of December 2022. It was escorted by at leats one Project 03160 Raptor-class patrol boat, the Mil Mi-8 helicopter with a subversive reconnaissance group and Project 22160 patrol ship with the Tor SAM as an anti-aircraft warfare.
Double defensive boom was placed at the entrance to the harbor of temporarily occupied Sevastopol no later December 17, 2022, according to the satellite image that H I Sutton posted in his Twitter. Booms were also set around anchorages and refuelling points for ships and submarines.

Presumably russians expect Ukrainian unmanned surface vessels not to overcome the obstacle due to small size. Similar defense strategy was common during World War I.
Also such extreme type of hostilities as torpedo boat raid on the anchorages was being used in those days. So defensive booms were a necessity since the aerial reconnaissance wasn’t well-developed.
There is a chance that aerial monitoring won’t detect small maritime drones and booms are required. Nevertheless, Ukrainian USVs with a 200 kilogram warhead can have a contact fuze that will certainly facilitate the passing of the defensive booms.

“Similar defense strategy was common during World War I.”
russian WW1 tactics have been outmaneuvered at every step by Ukraine during this war. I see this latest idea being no different. Remember the weird array floating radar that was supposed to save russian bridges, they worked out well didn’t they?
Okay, but that means these ships still cannot sail the Black Sea.
Once they leave the Navy base, it is “All you can fuck” for the drones.