Conditions & tides
Scored by DiveConnect's site-physics model
Marine forecast via Copernicus Marine. Score is a rule-based guide from swell/wind vs. the site's exposure — always dive your own assessment.
Dived here today? How were conditions vs. what we showed?
About this site
Fort Stark sits at the mouth of Portsmouth Harbor in New Castle, New Hampshire, where the Piscataqua River meets the Atlantic. The site takes its name from a former coastal defense installation that guarded the harbor entrance, with fortifications dating back to the Revolutionary era and expanded through the World Wars. Diving here would take place in the tidal waters just off this stretch of the Seacoast, an area known for strong currents moving in and out of the harbor.
AI overviewMarine life here
Confirmed by our research team, reported by independent divers, or observed nearby via iNaturalist — each entry is labelled with its source.
European Green CrabCarcinus maenasReported here · unconfirmed
Asian Shore CrabHemigrapsus sanguineusReported here · unconfirmed
Long-claw Hermit CrabPagurus longicarpusReported here · unconfirmed
Chain TunicateBotrylloides violaceusReported here · unconfirmed
Jonah CrabCancer borealisReported here · unconfirmed
Durable tips from divers — access, hazards, marine life, facilities. For day-of conditions, use the report tool in the conditions card above.
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