Socks and sea squirts

Carpet sea squirts (Didemnum vexillum) from Japan are moving around the world, presumably hitching rides on boats. In the UK there are currently nine known sites from the Solent to the Clyde, including Holyhead Marina. But Holyhead is the only site where pioneering action is being taken, by the Countryside Council for Wales, to repel the invasion.

They are bad news for our native species, likely to out-compete and smother them in a colonial carpet, hence the name carpet sea squirt. The commercial catalyst for taking action at Holyhead is the proximity and threat to the rich mussel beds of the Menai Strait from which five times the annual UK consumption is exported.

Leathery piece of carpet sea squirt

Considerable work has been done over the past couple of years to eradicate the squirts and I recently met up with the team of eight divers surveying the marina. The good news is that the vast majority of the squirts have been killed off with just a few surviving patches confined to chains that anchor the pontoons to the ocean floor.

The next step is to treat the chains before this season’s larvae are released and this will involve wrapping 150 chains in polythene and bleach. Typically the chains are about five metres long and the bleach powder will be packed into socks – about three socks per chain. So, if you are serving at a shop where someone approaches with a trolley of 225 pairs of socks, you will know that it’s not some sort of fetish but conservation in action.

Walking with wolves

Monday 2^ndJuly meet 12:45 for a 13:00 depart from Tan y Bwlch station on a guided walk into Coed y Bleiddiau, ‘forest of the wolves’, returning via the train leaving Dduallt at 15:30. Four hundred years ago wolves roamed this forest and legend has it that this is where the last wolf in Wales was slain.

In those days the land was owned by the Lloyds of Dduallt and their old house has recently been tree ring dated to 1559. In the census of 1841 there were 52 people living on their 600 acre farm; in the 2011 census there were only 5! Fortunately the land was acquired by the National Trust in the 1960s otherwise this beautiful oak woodland, managed by CCW, would be sitka spruce.

Huw Jenkins (that’s me) will lead this walk on behalf of the Snowdonia Society (Cwmdeithas Eryri). The route through the Maentwrog nature reserve stays close to the railway line but I’ve slashed an off-piste path through the bracken to show you some of my favourite bits.

The woods are full of birds singing away. I’m no bird expert but equipped with BirdVoice(a recent birthday present) we’ll see if together we can identify some of the many songs.

If you wish to join the walk the Snowdonia Society suggests you give them a donation of £2 if you are a member of the society and £5 if not. The one way ticket from Dduallt to Tan y Bwlch can be bought on the train and costs £2.40 or £2.20 for the over 60s. The Ffestiniog Railway have confirmed that the Tan y Bwlch café will be open.

We might see some goats but just in case we don’t, this is what they looked like a couple of weeks ago:

The Snowdonia Society is a registered charity working to protect, enhance and celebrate Snowdonia, its wildlife and heritage. The Society works with local communities, organisations and businesses to achieve this vision.

For full event details or to book a place contact Frances on 01286 685498 or email frances@snowdonia-society.org.uk