For one day every year, La Société Guernesiaise may organise trips over to the privately-owned island of Jethou. Yesterday I made my second ever trip, helping to lead two of the groups for ornithology and natural history, with Trevor Bourgaize. It is one of the smallest islands in the Bailiwick , a green gem rising out of the sea south-west of Herm. It benefits from being relatively undisturbed and is a good place to get close (some would say too close) to breeding gulls.
Coming into the tiny jetty, we had good views of Le Crevichon and could clearly see where granite has been quarried in the past. According to Prof. John Le Patourel, in ‘The Building of Castle Cornet’, a record dating from 1566 mentions iron and hammers being taken to ‘Le Creavissham’ to quarry the granite for Castle Cornet. Back then, the castle had to be partially reconstructed to accommodate the increasing use of gunpowder and canon. This quarry, more peaceful now than it was in the mid-sixteenth century, is a known spot for breeding Little Egret, Egretta garzetta, and we did see a few birds in the area, down on the shoreline.
In 1988, this showy bird was recorded just five times and was a ‘vagrant’ which meant that it turned up on Guernsey form time to time. In March this year, twenty-five were seen at the Reservoir on one day and they are now a common sight in reserves with reed beds and along the shore.
Each tour lasts about 90 minutes which is plenty of time to walk around the island, but as we were stopping to take in the wildlife it was rather a rush at the end.
From the jetty, we walked a clockwise route and soon had our first stop to admire a patch of Yellow Bartsia, Parentucellia viscosa. Viscosa because this annual is sticky. It is a semi-parasitic plant, absorbing water and minerals from other plants using root-like structures. It also makes its own food through photosynthesis – evident in the green leaves.
A little further along, on the cliffs that look back to Herm, Puffin and Fulmar are currently breeding and this is where they are most likely to be seen. The first group had good views of the Fulamr typically flying out from the cliffs and circling back on stiff, outstretched wings. They nest on the cliff ledges, Puffin nest in burrows under the grassy slopes. They will be gone by the end of July when the pufflings – what a lovely word – have fledged. They will stay out at sea through the autumn and winter until next spring when they return to land only to breed.
Further on is the gulls main breeding area. This is used by Herring Gull, Lesser Black-backed Gull and Great Black-backed Gull. The path passes very close to some of the nests which now have chicks and some gulls took to the air and made quite a commotion. Although not a real threat to people who just pass by, they can be intimidating and certainly there is the feeling that it is their territory. The Great Black-backed Gull is the largest of all gull species and will predate eggs, chicks and some adult birds of other species. Last year, I saw one with a spider crab which would have made a very tasty supper for me. It picked up the crab out of the shallow water, took it to the water’s edge, snapped off the claws and legs and just punched a hole into the underside of its body – all over and done with in five minutes. What a bird.
Jethou is a unique experience as each group had the island to itself and meant we could enjoy its tranquility, if only for a short time. The author, Compton Mackenzie was the tenant of Jethou from 1920 until 1934. There is a writing hut which he used on the other side of the pine trees in the last photo.
Natural history of the Bailiwick of Guernsey 