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THE OUTER REEF: 24-35mts.
Ireland · reef · advanced
24–35 madvancedDeepboat entry
THE OUTER REEF: 24-35mts.
The seaward side of Gurrig Island: ledged, wave-scoured rock from 24 m down to a boulder field that keeps going past 35 m.
Max depth24–35 m
Required leveladvanced
Entry typeboat
Visibility20 m
The dive
The Outer Reef is the seaward half of the pair Waterworld dives off Gurrig Island, at the western end of the Magharee Islands. The centre's own description is short and unusually blunt for a dive-centre page: wild rugged rock, a dive for the experienced, with ledges and crevices holding crawfish, squat lobster, spiny spider crab and cuckoo wrasse, dead man's fingers and sponges and anemones on the rock, and shoals of cod, pollack and mackerel over it. The depth band it publishes is 24 to 35 m.
There is a rare thing for an Irish dive site here: an independent, dated description of the same ground. A BioMar survey station 230 m south-south-west of the pin was dived on 23 May 1996, about 200 m off the west side of Gurrig. It logged a boulder and cobble field at 28 m sloping into deeper water, and inshore of it limestone bedrock falling away sharply in a series of ridges with sharp tops, interspersed with sand-covered ledges. The rock was heavily pitted and considerable surge was felt at that depth. Cover was red algae, dominated by Schottera nicaeensis on most rock surfaces even at 30 m, with relatively few animals visible; Alcyonium digitatum, the dead man's fingers the centre names, was there in moderate numbers, with Cliona celata, Pachymatisma johnstonia and the sea cucumber Aslia lefevrei in the crevices.
Those two accounts do not fully agree. The centre calls the site particularly rich; the survey found a red-algae reef with comparatively little animal life on the exposed faces. The older Irish dive guide to these islands explains the mechanism: in winter the south-west faces take the full force of the Atlantic gales, which have a sandpaper effect and leave very little growth, while the easterly faces carry kelp forest. This is one of the south-west faces. Expect scoured, sculpted rock with life concentrated in the crevices and under the ledges rather than covering the open surfaces.
Access is by boat only, ten to fifteen minutes out from Scraggane Pier at Fahamore. At 35 m this is the deepest of the pins Waterworld publishes for the Maharees, and the centre's own line about it being a dive for the experienced is the one to take seriously.
- Limestone ridges with sharp tops falling away between sand-covered ledges
- Boulder and cobble field at about 28 m sloping into deeper water
- Dead man's fingers in moderate numbers, recorded by both the centre and the 1996 survey
- Crawfish, squat lobster and spiny spider crab in the ledges and crevices
- Shoals of cod, pollack and mackerel over the reef
Please note before you go
- 35 m maximum depth, well past Advanced Open Water limits and into decompression planning on air
- Considerable surge was recorded here at 28 m by the 1996 BioMar survey; this is an exposed south-west face
- 8 to 17-18 °C water: drysuit or a thick wetsuit, and the training to use it
- Boat-only access with no shore exit anywhere on the island group
- The centre itself describes this as a dive for the experienced
Access & rules
Mandatory requirementsGetting there
Boat only, ten to fifteen minutes out from Scraggane Pier at Fahamore, north of Castlegregory. Waterworld's centre is about 30 m from the water at the pier and runs two boats, departing at 9am and 11am. A visiting club can launch its own RIB from the two slips at Scraggane, which has a wide gradually sloped slipway, toilets and ample parking; DUSAC reports no difficulty launching or retrieving except possibly at very low tide.
Operator
Access to the site runs through a local operator.
Rules and permits
The reefs lie within Magharee Islands SAC (site code 002261), designated by the National Parks and Wildlife Service for the habitat Reefs [1170]. No diving permit or fee is published for the SAC.
Season
Roughly May to September. Waterworld's own figures put the water at 8 °C at the start of the season and 17 to 18 °C in July, August and September. The older Dive Ireland guide records that in winter these islands take the full force of the Atlantic gales, and that this scouring is exactly what shapes the south-west faces like this one. The BioMar survey dived it on 23 May and DUSAC ran a club trip in June, so late spring is workable when the weather settles.
Conditions
Visibility20 m
Currentlight
Surgemoderate
WaterSalt water
Depth range24–35 m
Environmentreef
Coralnot sourced
Crowdsquiet
Waterworld gives visibility across its Maharees sites as about 40 m on very good days, around 20 m on average and about 7 m on bad ones; the Castlegregory village guide reproduces the same figures but puts the best days at 30 m, so plan on 20 m. Water runs about 8 °C at the start of the season and 17 to 18 °C in July, August and September. Boats leave Scraggane Pier at 9am and 11am and the run out is ten to fifteen minutes. Because this face looks south-west into the open Atlantic, swell rather than current is what makes or breaks the day.
On current: Dublin University Sub-Aqua Club, which dived the Maharees extensively in June 2009, records the sites as fairly non-tidal with only a small drift even at mid tide, and says the best diving in the group is around Gurrig Island. The older Dive Ireland guide warns of a good current on the third and fourth hours of the tide, but at Inishtooskert further east rather than here. Waterworld nonetheless tags this site as a drift as well as a reef and wall dive, so take the boat's briefing over either. Surge is the more relevant force on this face: the 1996 survey recorded considerable surge at 28 m.
Best months: May, Jun, Jul, Aug, Sep
Questions & answers
How deep is the Outer Reef at the Maharees?
Waterworld publishes it as 24 to 35 metres. The 1996 BioMar survey of the ground just south of the pin found a boulder and cobble field at 28 m that continued sloping into deeper water, so the 35 m figure is the working bottom rather than the seabed. That depth is beyond Advanced Open Water limits and needs deep training and a real gas plan.
Is the Outer Reef a hard dive?
Yes, by the operator's own account. Waterworld describes it as wild rugged rock and a dive for the experienced, and the BioMar survey recorded considerable surge at 28 m on this exposed south-west face. Combine 35 m, 8 to 18 °C water, a drysuit and Atlantic swell and it is not a site to make your first deep dive on.
How do you get to the Outer Reef?
By boat only, ten to fifteen minutes out from Scraggane Pier at Fahamore, north of Castlegregory in County Kerry. Waterworld runs two boats from the pier with departures at 9am and 11am. Clubs with their own RIB can launch from the two slips at Scraggane, which has a wide gradually sloped slipway, parking and toilets.
What will I see on the Outer Reef?
Waterworld lists crawfish, squat lobster, spiny spider crab and cuckoo wrasse in the ledges and crevices, with dead man's fingers, sponges and anemones on the rock and shoals of cod, pollack and mackerel above it. The 1996 survey confirms dead man's fingers in moderate numbers along with the boring sponge Cliona celata, Pachymatisma johnstonia and the sea cucumber Aslia lefevrei, but found the open rock dominated by red algae with relatively few animals showing.
Why is it called the Outer Reef?
The name is relative to Gurrig Island at the western end of the Magharee Islands: this pin sits on the seaward, south-west side and Waterworld's Inner Reef sits 730 m away on the landward side. The distinction is real underwater. The older Irish dive guide to these islands notes that winter Atlantic gales scour the south-west faces almost bare while the easterly faces carry kelp forest.
Is there current on the Outer Reef?
Little, according to the divers who know the group. Dublin University Sub-Aqua Club describes the Maharees sites as fairly non-tidal with only a small drift even at mid tide, and names Gurrig Island as the pick of the group. Waterworld still tags the site as a drift dive, and surge from Atlantic swell is the more relevant force on this face, so take the boat's briefing on the day.
When can you dive the Outer Reef?
Roughly May to September. Water is about 8 °C at the start of the season and 17 to 18 °C in July, August and September by Waterworld's own figures. Because this face looks straight into the open Atlantic, swell decides whether the boat can work it at all, and in winter these islands take the full force of the gales.
Life recorded at THE OUTER REEF: 24-35mts.
60 species within 1.5 km · OBISMola molarare · 2 records
Cliona celataoccasional · 7 records
Marthasterias glacialisoccasional · 6 records
Ophiactis ballioccasional · 6 records
Pachymatisma johnstoniaoccasional · 6 records
Thymosia guerneioccasional · 6 records
All 60 species recorded in this area
| Species | How often | Records |
|---|---|---|
| Cliona celata | occasional | 7 |
| Marthasterias glacialis | occasional | 6 |
| Ophiactis balli | occasional | 6 |
| Pachymatisma johnstonia | occasional | 6 |
| Thymosia guernei | occasional | 6 |
| Calliostoma zizyphinum | occasional | 6 |
| Echinus esculentus | occasional | 5 |
| Holothuria forskali | occasional | 5 |
| Homarus gammarus | rare | 4 |
| Maja squinado | rare | 4 |
| Dysidea fragilis | rare | 4 |
| Aplidium nordmanni | rare | 3 |
| Polycarpa scuba | rare | 3 |
| Cancer pagurus | rare | 3 |
| Sertularia argentea | rare | 3 |
| Asterias rubens | rare | 3 |
| Henricia oculata | rare | 3 |
| Aslia lefevrei | rare | 3 |
| Labrus bergylta | rare | 3 |
| Haliclona (Haliclona) simulans | rare | 3 |
| Hemimycale columella | rare | 3 |
| Haliclona (Haliclona) urceolus | rare | 3 |
| Dercitus (Dercitus) bucklandi | rare | 3 |
| Aplidium punctum | rare | 2 |
| Ascidiella aspersa | rare | 2 |
| Diazona violacea | rare | 2 |
| Botryllus schlosseri | rare | 2 |
| Scyliorhinus canicula | rare | 2 |
| Obelia geniculata | rare | 2 |
| Nemertesia antennina | rare | 2 |
| Luidia ciliaris | rare | 2 |
| Amphipholis squamata | rare | 2 |
| Pollachius pollachius | rare | 2 |
| Parablennius gattorugine | rare | 2 |
| Centrolabrus exoletus | rare | 2 |
| Ctenolabrus rupestris | rare | 2 |
| Taurulus bubalis | rare | 2 |
| Mola mola | rare | 2 |
| Raspailia (Raspailia) ramosa | rare | 2 |
| Tethya citrina | rare | 2 |
| Aplysia punctata | rare | 2 |
| Patella pellucida | rare | 2 |
| Antiopella cristata | rare | 2 |
| Myxilla (Myxilla) incrustans | rare | 2 |
| Protosuberites incrustans | rare | 2 |
| Haliclona (Rhizoniera) viscosa | rare | 2 |
| Spongosorites calcicola | rare | 2 |
| Rocellaria dubia | rare | 2 |
| Steromphala cineraria | rare | 2 |
| Clavelina lepadiformis | rare | 1 |
| Polyclinum aurantium | rare | 1 |
| Dendrodoa grossularia | rare | 1 |
| Cetorhinus maximus | rare | 1 |
| Inachus phalangium | rare | 1 |
| Necora puber | rare | 1 |
| Aequorea forskalea | rare | 1 |
| Aglaophenia pluma | rare | 1 |
| Kirchenpaueria pinnata | rare | 1 |
| Leuckartiara octona | rare | 1 |
| Sertularella gayi | rare | 1 |
Nearby sites in Magharee Islands, Castlegregory
Explore all sitesThe Pinicale: 14 to 18 mts0.4 km
Magharee Islands, CastlegregoryA gully between Gurrig Island and its offshore pinnacle, walled with soft coral and anemones and petering out into kelp and swim-throughs.
OverHang 16-20mts0.4 km
Magharee Islands, CastlegregoryA Gurrig Island rock face of anemone-covered overhangs and a small cave, worked between 16 and 20 m.
THE CROSS ROADS: 20-22mts0.4 km
Magharee Islands, CastlegregoryOne of five named dives Waterworld works on the reef around Gurrig Island: crossed rock gorges at 20-22 m, read by the operator as two ancient river channels meeting.
THE INNER REEF: 18-33mts0.7 km
Magharee Islands, CastlegregoryKelp on the top, then a clean rock wall running roughly half a mile down to sand at 33 m, on the landward side of Gurrig Island.
Square Rock 12-22 mts1.6 km
Magharee Islands, CastlegregorySquared-off rock forming gullies and swim-throughs at 12 to 22 m in the channel between Inishtooskert and Illaunimmil; the only published description is one sentence long.
THE POINT: 18-22mts.1.6 km
Magharee Islands, CastlegregoryBoulders, overhangs and anemone-covered canyon walls at 18 to 22 m, in the middle of the Magharee Islands where the dive centre's named sites cluster.
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