Diving in Tenerife

Autumn through winter, roughly September to March, when Squatina squatina rests camouflaged on sand at sites along the south, west and southwest coast, including Abades and Radazul. This is a Critically Endangered species: sightings are never guaranteed, and the responsible approach is to keep distance and never disturb a resting shark.

Not usually underwater. The resident population of short-finned pilot whales off the southwest coast, between Los Cristianos and Costa Adeje, is a boat-based whale-watching draw rather than something divers encounter on a dive. Dolphins turn up in the same waters and occasionally elsewhere around the island, again mostly as a surface, boat-based sighting.

No. Two Natura 2000 conservation zones cover parts of the coast, Teno-Rasca along the west and Sebadales del Sur along the south, but neither is a fishing reserve and neither requires a diving permit, fee or quota. Most of the island's coast carries no formal protection status at all.

Both, depending on where you go. The south, southeast and east coast run mostly shallow, shore-accessible bays suited to Open Water divers and try-dives. The north cluster off Puerto de la Cruz and several west-coast lava tunnels run deeper, current-affected and boat-only, better suited to Advanced Open Water divers and beyond.

La Rapadura, off Puerto de la Cruz: a wall of hexagonal basalt columns diving to 45m, boat-only and rated for expert divers, with a National Geographic cover credit to its name. Valle de los Peces nearby runs even deeper, to 50m, for divers who want the cluster's most demanding profile.

Yes, mainly around Palm-Mar and Tabaiba. El Condesito is a broken, shallow wreck at 9-18m suited to newly certified divers, while El Meridian nearby is an intact hull at 18-30m for advanced divers. Tabaiba's tugboat, deliberately sunk in 2006, sits further east and is penetrable for trained divers.

Warm enough to dive year-round. Summer bottom temperatures run roughly 22-25C, dropping to about 17-19C in winter. A 5mm wetsuit covers most of the year; bring a 7mm or a hood for winter dives, especially on the deeper north and west-coast sites.

Yes, particularly off Puerto de la Cruz and around Garachico and Los Gigantes. Tubo de Garachico runs a single 150-metre passage to a basalt arch, and Labyrinth and La Catedral hold a cave maze and a skylit chamber. Most of these are advanced-rated overhead dives with natural light and a single route, not technical cave penetration, but they still call for AOW-level buoyancy and overhead experience.