Find comes months after Russian vessel monitored off Pembrokeshire coast
A SUSPECTED Russian sonobuoy – the type used to track submarine movements – has been recovered from the seabed off Skomer Island, just months after a notorious Russian spy ship was monitored operating off the Welsh coast.
Volunteer divers from Neptune’s Army of Rubbish Cleaners (NARC) discovered the cylindrical device on Saturday, November 15, during a routine seabed clean-up near Wooltack Point. The object, heavily encrusted with marine growth, appears consistent with sonobuoy equipment used by foreign militaries for underwater surveillance. The team also removed discarded fishing weights from the conservation zone.
Sonobuoys are typically deployed from aircraft and use a combination of hydrophones and radio transmitters to detect submarine activity. Some work passively by listening for acoustic signatures; others emit sound pulses and analyse returning echoes, relaying information back to surface vessels or aircraft.
NARC has passed the object to the relevant authorities for assessment.
A wider pattern of activity
The discovery comes at a time of heightened concern about Russian intelligence-gathering in UK waters.
This week, Defence Secretary John Healey confirmed that the Russian spy ship Yantar, part of Moscow’s deep-sea surveillance fleet, has been operating on the edge of UK territorial waters. RAF pilots monitoring the vessel reported that Yantar directed lasers at their aircraft, an action the Defence Secretary described as “deeply dangerous”.
Mr Healey said the UK has “military options ready” should the ship move further south.
Yantar is designed to map, inspect and, if necessary, sabotage undersea infrastructure – including the fibre-optic cables and pipelines that support the UK’s energy supply, internet traffic and banking systems. NATO intelligence agencies have repeatedly warned that Russia’s deep-sea programme poses a strategic threat to Western infrastructure.
It is the second time this year that Yantar has entered the UK’s wider waters. In July 2025, the vessel was tracked off the Pembrokeshire coast, prompting RAF surveillance flights and a Royal Navy frigate being dispatched to shadow its movements. At the time, defence sources told The Herald that the vessel was “lingering unusually close to sensitive undersea cables”.
Local concerns
While the origin of the recovered Skomer device has yet to be formally confirmed, its appearance near a protected Welsh marine site has raised eyebrows – especially given recent Russian movements around the British Isles.
Security analysts note that sonobuoys are sometimes lost or abandoned during military exercises, but the proximity to Skomer’s conservation zone and the timing of the find are notable.
Meanwhile, NARC continue their regular clean-up dives around Pembrokeshire, removing hazardous debris to protect the region’s internationally recognised marine habitats.
