The crawfish of Sark, fished out and coming back

Sark’s waters are the only place in the British Isles where crawfish are fully protected. The 2024 survey report goes further and calls them the only such waters in the British Isles and Europe. Behind that law sit fifty years of loss, three snapshot surveys and a recovery that has not moved in a straight line.

How the crawfish disappeared

The crawfish is the spiny lobster, Palinurus elephas, and during the 1960s and 1970s it was fished to commercial extinction in the Channel Islands. Commercial extinction means what it sounds like: too few left for catching them to pay.

Then, from 2014, good numbers of juveniles began reappearing around the Channel Islands and southwest Britain, roughly four decades after the fishery collapsed.

In January 2018, an amendment to the Fishing (Sark) Ordinance gave crawfish protected status for three years, to let the stock re-establish, and in 2021 the protection was extended for three more. No other waters in the British Isles protect the species fully.

What the dive surveys found

Whether the protection is working is measured the slow way: snapshot dive surveys of eight reef sites around the island, in 2017, 2020 and 2024.

The 2017 survey counted 15 crawfish, with no juveniles among them. The 2020 survey found an increase at most sites, about 30 animals in total, and every one of them was an adult. Still no juveniles.

The 2024 survey, carried out by Sue Daly with marine biologist Fiona Crouch, counted 17, down at every site but one. Only four were at or above the 23 centimetre legal landing size. Most of the rest were juveniles of 7 centimetres or less, the first juveniles recorded in the whole series.

Read that honestly and it cuts both ways. The count nearly halved, and the large animals largely vanished. At the same time, divers saw young crawfish on these reefs for the first time in the series, which is what a re-establishing population should produce. Three snapshots cannot settle which signal wins.

The octopus question

The 2024 report offers one possible explanation for the drop in large animals: octopus predation. That is the report’s suggestion, not a verdict.

The suggestion has a history of its own. Octopus were once abundant around Sark, until the severe winter of 1962 to 1963 froze the sea edges and wiped them out. From 2023, Sark fishermen began finding octopus in their pots again, part of a wider return across the Channel Islands, southwest England and northern France that marine biologists link to rising winter sea temperatures. If the report’s suggestion is right, one recovery may be complicating another, sixty years after both species were in trouble.

Why nobody will tell you where the reefs are

The survey reports never give the locations of the eight sites, recording them only as letters, Site A to Site H.

That secrecy is the honest choice. A small, slow-growing, fully protected population with its map references published would be simple to strip in a season. The reports share every number that informs a reader and withhold the one detail that could undo the work. Every count from all three surveys, site by site, is on our crawfish survey page.

Why this matters when you visit

Stand on the cliff path, or float in a bay after a wild swimming session, and you are looking at the only waters in the British Isles where this animal is left entirely alone. Most recovery stories reach you as headlines about somewhere far away. This one is happening under the surface of the sea you crossed to get here, counted by divers, kept deliberately quiet, and still undecided. Sark is small enough that a single ordinance covers every reef around it, and that scale, where one decision can shelter a whole population, is worth understanding about the island before you ever pack a bag.

The Getting to Sark guide covers the crossing, and the crawfish survey page has the full dataset behind this article.