The weekly briefing.

Navigation Warning 473/2026 has been cancelled. Vessels that had marked restrictions from that notice should update passage notes and verify the current status with the Hellenic Navy Hydrographic Service if operating in the affected area.

The red light on the west side of the entrance to Mytilini inner harbour, at position 39°06.18'N 026°33.36'E, is reported unlit. Vessels approaching Mytilini after dark should mark the defect and use additional caution until the light is restored.

R/V Aegaeo is conducting seawater, plankton and sediment sampling from 3 May 2026 until further notice across the South Aegean, North and South Cretan Sea, Myrtoo, Karpathio, Rhodes and Kastellorizo sea areas. A wide berth of 0.2 nautical miles is requested around the listed sampling positions.

A temporary red flashing light has been established at Monemvasia Marina on the east coast of the Peloponnese at 36°41.04'N 023°02.23'E. The light has a focal plane of 6 metres and nominal range of 3 nautical miles; vessels using the marina should update local pilotage notes.

Port construction and dredging operations are in progress at Skopelos from 4 May 2026 until further notice, with a separate sea area designated for dropping dredged material. Vessels approaching Skopelos should review the coordinates in the notice and proceed with caution around the works and disposal areas.

Subsea operations by the vessel Ocean Link are being carried out in the Central Aegean from 2 May 2026 until further notice along the line of positions listed in the notice. A wide berth is requested, so vessels transiting the area should plot the line before passage.

A sailing race is being conducted in the Porto Rafti sea area on 1 May until sunset, and on 2 and 3 May from 0800 UTC until sunset. A wide berth is requested around the race area bounded by the coordinates in the notice.

Navigation Warning 546/2026 has been cancelled. Update any operational restrictions or chart notes derived from that warning and verify with the Hellenic Navy Hydrographic Service if there is any doubt.

Three green stable lightbuoys have been established in Nydri Port, Lefkada, with 6 metre focal planes and 3 nautical mile nominal range. Vessels using the North Ionian Sea and Lefkada/Nydri area should update local buoyage notes and confirm positions before night navigation.

Navigation Warnings 476/2026, 533/2026 and 536/2026 have been cancelled. Vessels should remove associated temporary restrictions from passage plans once the cancellation is confirmed against onboard publications.

Until 20 June 2044, navigation, anchoring, dredging, diving and bathing are prohibited inside the defined marine culture area off Gruissan, with limited exceptions for authorised operators, scientific vessels and professional fishing outside the stricter inner zone. Vessels operating on the Aude coast should plot the published boundary coordinates before approaching the concession area.

The Maritime Prefecture has abrogated Order 433/2025, which regulated navigation, anchoring and diving off the Saint-Tropez coastline. Operators that had marked those temporary restrictions should update passage and anchorage notes, while continuing to observe the standing Mediterranean anchoring framework.

The Maritime Prefecture has abrogated Order 377/2025, which had regulated navigation, anchoring and diving off Saint-Raphaël following discovery of an explosive device. Vessels that had retained the temporary exclusion in local notes should remove it after confirming no new local notice has replaced it.

Akrocéan is authorised to install and use a floating LiDAR research buoy at 43°01.440'N 004°16.822'E until 31 March 2027 for wind, wave and current measurement linked to floating wind development. Navigation, anchoring, diving, bathing, fishing and dredging are prohibited within a 500 metre radius except for authorised service, safety and emergency vessels.

From 1 May to 31 July 2026, navigation, anchoring, stopping of registered vessels and craft, and scuba diving are prohibited in 16 defined zones protecting 18 osprey nests on the western coast of Corsica. Vessels cruising around Calenzana, Galéria, Osani, Partinello, Ota, Piana and Cargèse should plot the annexed zones before coastal navigation or tender operations.

The Fiumicino harbour office has issued Ordinance 47/2026 for an open drifting fishing competition at sea. Vessels operating off the Rome/Fiumicino coast should review the PDF for the competition area, time window and safety restrictions before passage.

From 5 to 30 May 2026, a 10 metre radius area off the head of the breakwater mole at Maiori harbour is restricted for installation of a briccola/mooring point. Navigation, anchoring, stopping, bathing, fishing and diving are prohibited in the work area, and vessels entering or leaving Maiori must proceed at minimum safe speed without planing.

Club Nautico Versilia will run the XXIX Trofeo Challenge Ammiraglio Giuseppe Francese offshore sailing race from 1100 local time on 9 May to 0800 on 10 May, on routes between Viareggio, Isola del Tino and Marina di Pisa. Nearby vessels must keep clear of racing yachts, proceed at minimum steerage speed and follow instructions from safety units.

Live artillery firing exercises from Punta Castagna will take place in the Tango 803 sea area on 6, 7, 14, 19, 20, 27 and 28 May and on 9, 11, 18, 24 and 25 June 2026, from 0800 to 1700 local time. Navigation, stopping, fishing and surface or underwater activity are prohibited in the Viareggio jurisdictional part of the area during active periods.

A spearfishing competition will take place off Cecina and Vada from 0730 to 1330 on 10 May 2026, with 31 May as reserve date. Navigation, stopping, landing, fishing, bathing and any diving activity are prohibited inside the marked race field during the event.

The entrance and exit of Cetara harbour are closed to all vessels from 0800 to 1200 on Tuesday 5 May 2026 while pontoon Antonio unloads stone material for the new submerged breakwater. Navigation, anchoring, stopping, bathing, fishing and related marine activities are prohibited in the work area during the operation.

The La Maddalena harbour office has issued Ordinance 050/2026 for works in the Padule area. Vessels, tenders and diving activity around La Maddalena should review the ordinance and keep clear of the works area until the restriction is lifted.

Mazara del Vallo port is affected by widespread silting and variable depths. Until further notice, access to the Porto Nuovo is limited to vessels with maximum draught of 5.20 metres, vessels between 4.50 and 5.20 metres must monitor tides and maintain at least 50 centimetres under-keel clearance, and berthing at Ruggero II is limited to vessels up to 4.50 metres draught.

The Gargano Triathlon Sprint swim leg will take place off Spiaggia Castello, Manfredonia, on 10 May 2026 from 0900 until the end of the race. Navigation, anchoring, stopping, diving, fishing and other surface or underwater activity are prohibited within about 100 metres of the race field.

From 4 to 31 May 2026, during daylight and favourable weather, pontoon Cobra will transfer inert material from the Malamocco area to the Mo.S.E. artificial island at the Lido inlet. Vessels transiting the Malamocco inlet and the channel behind the Mo.S.E. island must keep a safe distance, reduce to minimum steerage speed and avoid creating dangerous situations around the working vessel.

Transport Malta has issued the formal cancellation of the earlier notice reporting the East Cardinal Buoy at Merkanti Reef as destroyed. Vessels operating in Maltese waters should update chart notes and confirm the current buoyage status before passage near Merkanti Reef.

The Marshall Islands Registry sets out the shared responsibilities of Recognized Organizations and Aviation Inspection Bodies for plan review, approval, survey, audit and certification of helicopter landing areas on RMI-flagged yachts. Yacht managers with helicopter facilities should check that structural, firefighting, refuelling, hangar, safety management system and operations manual responsibilities are allocated correctly, and note that a Helicopter Landing Area Technical Certificate is not an operational Helicopter Landing Area Certificate.

The Cayman Islands Shipping Registry updates guidance on large yacht heliports, including the REG Yacht Code Annex H framework, Aviation Inspection Body and Recognized Organization roles, equivalent arrangements, initial certification, firefighting systems and periodic inspections. Owners and managers should confirm that operational intent, aircraft selection, SMS aviation elements, heliport operations manual, crew training, annual inspections and any private-use helicopter operations are addressed before helicopter use.

Lloyd's Register reports that MEPC 84 met in London from 27 April to 1 May 2026 and continued work on the IMO Net-Zero Framework without reaching a compromise position, with further intersessional GHG meetings planned before MEPC 85. The summary also flags agreed ballast water amendments, a new North-East Atlantic ECA for NOx, SOx and particulate matter, and continuing work on strengthened SEEMP requirements.

DNV reports that MEPC 84 continued discussions on the IMO Net-Zero Framework after the October 2025 extraordinary session was adjourned, with divergent positions still unresolved. Operators should track the next GHG intersessional work because DNV also notes progress on supporting technical guidelines, ballast water survey and testing requirements, NOx certification for alternative fuels, and amendments linked to the North-East Atlantic ECA.

DNV's Q1 review reports 64 detentions for DNV vessels, compared with 52 in Q1 2025, with shortcomings in safety management implementation, maintenance, fire detection, fire doors, emergency fire pumps, drills and emergency generators recurring as detention drivers. Operators should prepare for the Paris and Tokyo Memoranda cargo securing campaign from September to November 2026 and current fire-safety inspection focus areas.

The Shipowners Club summarises the EU's 20th Russia sanctions package, including 46 additional shadow fleet vessel listings, tanker sale due-diligence obligations, transaction bans on Murmansk, Tuapse and the Karimun Oil Terminal, and future maritime services restrictions linked to Russian oil and LNG activity. Members are reminded that cover is not available for trade breaching applicable sanctions and that due diligence records should be retained.

The Shipowners Club article, developed with Nautical Nexus, discusses how artificial intelligence, natural language processing and onboard behavioural data may supplement audits by detecting fatigue, communication breakdowns, procedural drift and equipment interaction risks in real time. Operators considering such tools should also address privacy, consent and flag-state or data-protection requirements before deployment.

Pantaenius sets out practical sustainability measures for boat owners, framed around reducing pollution, emissions, chemical runoff and waste while cruising. Captains can use the article as a prompt for onboard housekeeping, provisioning, maintenance and waste-management reviews before the main season.