Koster Islands & Kosterhavet · Sweden · Wall
Yttre Vattenholmen
Overhangs, some deep enough to border on caves
Photo: Bengt Littorin · CC BY 2.0
Yttre Vattenholmen is an exposed island off Tjärnö, dived on the wall of its east side. The rock is thick with dead man's fingers and plumose anemones, and divers come for the overhangs and the squat lobsters, edible crabs and decorator crabs on the wall.
Also known as Yttre Vattenholmen (Östersida), Yttre vattenholmen.
Where it is and how deep
58.8755° N, 11.1062° EApproximate position — the dashed circle shows where the site lies; your operator's briefing has the mooring.
The dive
From the jump the dive follows the wall, which is covered in dead man's fingers and plumose anemones with squat lobsters, edible crabs and decorator crabs among them. Lobster, cod, cuckoo wrasse, nudibranchs and dahlia anemones turn up on some dives. The face is cut by many overhangs, some of them deep enough to border on caves, and the wall ends on a shell-gravel bottom at 25 m.
Marine life and season
- Nudibranchs
- Macro critters
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Good | Good | Good | Fair | Fair | Fair | Good | Good | Good | Good | Good | Good |
Season follows Koster Islands & Kosterhavet: Boats run all year and no month stands out; spring and early summer bring brown, low-salinity surface water.
Know before you go
- A very exposed spot with plenty of waves, so the moment of jumping in has to be judged with care.
- Heavy motorboat traffic in summer; dive with a flag and keep a close watch on the boat.
Dive videos
Yttre Vattenholmen 2020-08-29 - Kosterfjorden. Sjukt bra sikt denna dag. Diving in Sweden · Magnus Alexandersson on YouTube
Yttre Vattenholmen Dyk 2 med hummer på rymmen - 2020-08-09 - Diving in Sweden Kosterhavet · Magnus Alexandersson on YouTube
Sources
- Yttre Vattenholmen (Östersida) dykplats | dykarna.nu — dykarna.nu
Photo credits
- Dense underwater forest of olive-brown kelp blades and serrated green fronds over rock covered in red and brown seaweeds, with green-blue water above by Bengt Littorin, CC BY 2.0, via Wikimedia Commons
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Reef
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