I was having a mooch around the vegetation by the River Ely at Cardiff’s Grangemoor Park on Thursday when an official-looking chap approached and asked if I was surveying. I explained that my activity wasn’t anything official but that I am a biodiversity recorder and also that I write this blog … and so we got chatting. It turned out that he is the ecologist for the Cardiff Harbour Authority, and he was there on official business.

Presumably due to the hot temperatures in recent months, the Ely has had a lot more vegetation than usual growing on its surface this summer. I don’t know anything about water vegetation – some might have been algal bloom, some various types of plants that grow in water. On the opposite side of the river from Grangemoor Park there have also been several large raft-like clumps of vegetation that have grown and expanded considerably during the summer. It was these that had prompted the ecologist’s visit as they are, in fact, the highly invasive plant Water-primrose (Ludwigia grandiflora).

Legally, in the UK, Water-primrose is a ‘species of special concern’; unless you have a special exemption, you are not permitted to grow it, sell it, release it into the environment (the National Wildlife Crime Unit website has the full list of regulations), and you must report it if you see it. Of course, if I had known what it was, I would have done that; fortunately, a well-known Cardiff ecologist spotted it and recorded it on 19 August. That was the first time this plant has been recorded in Wales.

The CHA ecologist had subsequently been notified about the plant, as had Defra, the UK government’s Department for Environment, Food & Rural Affairs, and the ecologist told me that a specialist team from Defra would be coming to endeavour to remove the plants this coming week. As you can see from my photos, the Water-primrose is in full bloom, so the authorities will want to remove it before it seeds to prevent its spread. The plant also grows easily from cuttings, so they will have to be especially vigilant about removing all the material. Needless to say, if those of you who live in Britain ever see a plant like this growing in any waterway near you, please do report it to Defra, or your local environmental authority.