Master's MateSafety Initiative Network
The Master's Mate Safety Initiative Network (MMSIn) — like AAA for the ocean, but free & community-driven. Cruisers keeping each other safe: anchor-drag & distress alerts, a verified captains directory, and a watch network that has your back.
Tug
SEIYO MARU
Tug · last seen 35°N 135°E · Jun 2026 · MMSI 431301711 · Call sign JI3719
Not yet on Master's MateType
Tug
Length
44 m
Beam
11 m
Draft
4.7 m
Call sign
JI3719
First reported
Jun 2026
Last reported
Jun 2026
AIS reports
6
SEIYO MARU is a 44-metre tug. Her hull carries 11 metres in the beam and a draft measuring 4.7 metres. Her papers read MMSI 431301711, call sign JI3719. Add SEIYO MARU to the Master's Mate Safety Initiative Network — free to join, and the fleet keeps an eye out for each other.
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Built for boats that work — like SEIYO MARU.
Engine & systems telemetry, live AIS, weather and distress alerting for the vessels that earn their keep.
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Live AIS position · Jun 15, 2026 11:29 UTC
Position
34.6605° N, 135.4394° E
Status
Moored
Speed
0.0 kn
Course
291°
Destination
JP AMX
ETA
05-21 06:30 UTC
Working the Sea of Japan? You're never out there alone.
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Joining the Safety Initiative Network doesn't just put SEIYO MARU on the map. It hands you the full bridge:
Systems Monitoring
Batteries, bilge, tanks, Victron & NMEA 2000 telemetry — your whole boat on one dashboard.
Live AIS & Traffic
See every vessel around you in real time. Closest-approach warnings before they matter.
Weather & Routing
GRIB wind, swell & current on the chart. Plan passages with ETA-calibrated forecasts per leg.
Distress Mesh
Mayday & Pan-Pan that ripple out to nearby cruisers — a watch network that has your back.
Anchor Watch
GPS-precise drag alarms that actually wake you — and your whole crew. Sleep through the night.
Worldwide Charts
Navionics-grade vector charts, satellite & raster overlays, online or off. Your whole cruising ground.
Onboard Cameras
Watch your boat from anywhere — live feeds and 24h recording, straight from your gateway.
Hail Any Captain
A verified captains directory + direct hailing. Reach the boat next to you, or across the bay.
Claim SEIYO MARU and switch it all on
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About SEIYO MARU
What kind of vessel is SEIYO MARU?
SEIYO MARU is a Tug.
Where was SEIYO MARU last seen?
SEIYO MARU was last reported in the Sea of Japan in Jun 2026 on public AIS.
What is SEIYO MARU's MMSI?
SEIYO MARU's MMSI is 431301711. Call sign JI3719.
How big is SEIYO MARU?
SEIYO MARU is about 44 m long, 11 m on the beam, drawing 4.7 m.
Is SEIYO MARU on the Master's Mate Safety Initiative Network?
Not yet. If SEIYO MARU is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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