Stallion Rock is the top of an underwater cliff that is almost entirely obscured at high tide. A veritable hidden gem, Stallion Rock is vertical in the middle with rounded shoulders and has an undercut base along almost all its length. This is a lovely rock pinnacle with vertical walls down to around 35m, an abundance of wildlife and excellent visibility (anything up to 10m).
A typical dive would be to free fall down the face starting just outside of the rock and descending past the overhang at 23m. At 32m the undercut provides a dramatic overhang to explore. When the bottom is reached at 35m, either choose to go north or south and follow the base along until ascending back up the face. The main face is smooth with some diagonal and horizontal cracks. Either side of the face is mostly sand and shells with some scattered boulders. There is some tidal movement, especially around the surface of the rock.
There is an impressive amount of life with sea squirts (yellow ringed, light bulb, gas mantle, leathery, red and fluted squirts), encrusting and cup sponges, tubeworms, common prawns, cushion stars, sea lemons, decorated crabs and squat lobsters in every available crevice. Fish such as dogfish, conger eels, cod and pollack congregate under the overhangs at the base or cruise in the current at the shoulders. There is some life on the face itself, notably plate shaped sponges (Axinella infundibuliformis) attached to the main face. The wall plunges from the surface to 30m or so and is covered in life. Anemones observed on this site include sealoch anenomes and protanthea anemones, thought to be specific to Scottish sea lochs and discovered relatively recently. There are even occasional scallops to be found on the sandy bottom.
It is worth noting that Seasearch Surveyor George Brown photographed a remarkable encounter in Loch Fyne in November 2012, whilst diving from Fyne Pioneer. At Stallion Rock, George descended to 18m and found a small indentation in the wall at the back of which was a sessile ascidian. After taking some photographs, the ascidian was witnessed lunging at a small amphipod, perhaps 2-3mm in length, and then swallowing it whole. It has only been possible to identify this as a predatory ascidian, normally found at depths of 1,000- 2,000m.
Swimming too close to the wall will disturb the sediment and impair visibility. The visibility is usually good but even so it is normally pitch black at the base of the wall. Some tidal movement can be present which speeds up as it goes round the rock especially near the surface but is not normally a consideration. After heavy rains, the visibility can drop to around 3m due to silt run off from the shoreline and the consequential halocline. Dropping under the silt-line, the visibility will improve again but sunlight will be quickly absorbed by the combination of silt above and depth below. A good torch and back up is essential.
The rock formation, darkness and depth make for a very atmospheric experience. This wall dive is considered one of the most impressive in any Scottish sea loch and is rated with many open-ocean sites.
