Nocturnal Intertidal Marine Biology & Invertebrate Ecology

Four nights on the reef at minus tide, with red light and UV torches, watching what only comes out after dark.

Booking now
Each session2 hr 30 min a session
How oftenOnce a week
Cohort8–10 per cohort
SeasonNovember – March · scheduled against verified minus-tide nights

What you leave with

Octopus, nudibranchs and biofluorescent anemones, seen with your own eyes at night

Rocky coastal reefs during winter extreme low tides, at night. Nocturnal behaviours, biofluorescence, hunting octopus, foraging crabs and anemones that glow under UV.

The tide table decides the dates, not us. Sessions are published a season ahead against verified minus-tide events.

What makes this one worth it

  • Night Navigation, Reef Safety & Night Eyes
  • Cephalopod Hunting & Nocturnal Crustaceans
  • Biofluorescence & Ultraviolet Exploration
  • Nudibranchs, Moray Eels & Marine Conservation

What is included

  • All 4 sessions of the 4-week cohort — 10 hours of instruction
  • A place held for you for the whole run, in a cohort of 8–10
  • Every piece of equipment listed below, provided on the day
  • Your instructor, and their attention in a group this size

What to bring

  • Water, and something to eat if you want it
  • Nothing else — the kit is provided

How it runs

Once a week · 2 hr 30 min a session

Frequency
1x / week — 2.5 hours, on negative winter night tides
Session length
2 hr 30 min
Each month
4 sessions, about 10 hours
Cohort size
8 – 10 participants
Where
Bird Rock / Sunset Cliffs rocky intertidal reefs
Level
All Levels (sturdy footwear required)
Commitment
Monthly — stay as long as it is worth it

What you cover, in rotation

The group works through these in order and then begins again on fresh ground. Join at whatever stage it is on — nothing here assumes you were there for the last one, and nothing runs out — or drop in for a single session if that is all you can manage.

  1. Stage 1Night Navigation, Reef Safety & Night Eyes
    • Tide tables, reading minus tide curves, and night reef walking safety.
    • Preserving night vision with red spectrum LEDs.
    • Intertidal topography and navigating wet sea lettuce and barnacle fields.
  2. Stage 2Cephalopod Hunting & Nocturnal Crustaceans
    • Spotting the two-spotted octopus hunting on open reef.
    • Striped shore crabs, kelp crabs and spider crabs.
    • Hunting strategies and camouflage shifts under low light.
  3. Stage 3Biofluorescence & Ultraviolet Exploration
    • 365nm UV torches revealing biofluorescence in anemones, corals and worms.
    • The chemistry of green and red fluorescent proteins.
    • Plankton sampling and bioluminescent dinoflagellate flashes.
  4. Stage 4Nudibranchs, Moray Eels & Marine Conservation
    • Finding Spanish Shawl nudibranchs and sea hares.
    • Spotting California moray eels in deep crevices.
    • A hot tea gathering at the trailhead and a species debrief.

4 sessions in the cycle, then it begins again on new ground.

Who leads it, and what is provided

Led by Marine biologist / intertidal invertebrate researcher.

Low-tide window scheduling, reef safety, and scientific interpretation.

On the table when you arrive

  • Waterproof red LED headlamps
  • 365nm UV torches
  • Viewing scopes
  • Species field guides

Before you book

Know before you go

  • Dates are set by the tide table and published a season ahead
  • Sturdy closed footwear with grip is required — the reef is wet rock

Cancellations and refunds follow our cancellation policy, which is the same for every activity on this site.

When it runs

August 2026

M
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W
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Runs Not running

Saturday 8 August

  • 6:30pmup to 10 guests

Usually runs Saturdays.

This is the operator’s schedule, not live seat availability. We check the date with them and come back to you — nothing is booked or paid for here.

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