Blue green algae

3 August 2019

This morning, as we crossed the road to the Common, Ian, the ranger, was letting a black car through the gates. Commando and I wondered what the people in the car were doing but, as it went in the opposite direction to us we soon forgot about it in the hustle bustle of the parkrun set up.

My plan for the morning mostly involved walking across the Common towards the Beyond Graffiti Tunnel to have a look at the newly repaired bridge across Rollesbrook Stream. At the beginning of last month I noticed the little railway sleeper bridge had collapsed and, a week or so ago, some friends told me it had been fixed so I thought it would be a good mission for the morning. When parkrun RD, Kate, mentioned there was an issue with some kind of algae in the Boating Lake I thought I’d have a look at that too as it was on the way. To be honest I wasn’t overly concerned about the algae. It’s been such a hot humid summer everything seems to have grown like mad and algae sounded fairly innocuous.

As I climbed to the top of the hill by the lake the water did look quite green and the black car I’d seen earlier was on the path on the far side along with Ian and his truck. Perhaps they were there to look at the algae? As one of the cygnets was close to the path on my side of the lake, I was far too interested in taking photos to think much about it.

While I was snapping away a woman came over to me. She was casually dressed in cropped jeans and a T-shirt but, as she was wearing blue surgical gloves, I imagined she was something to do with the people in the black car and was there to look at the algae.

“Someone has poured paint into the lake” she said, “The Environmental Health people are here with Ian looking to see what can be done. One of the cygnets looked sick so Ian and I managed to catch it but I’m worried about the others and the adult swans.”

This explained the car on the other side of the lake. It also made me quite angry. Why would anyone want to pour paint into the lake and how on earth were they going to get it out?

From where I was standing I couldn’t see any paint but the lady, who introduced herself as Sue, told me it was on the other side and was quite bad. As the adult swans were swimming where she had just pointed this was a bit of a worry? If the poor things got paint on their feathers they could easily ingest it and get sick. Perhaps that was what had happened to the cygnet?

When Sue first came over I thought she was one of the people from the black car. Now I realised she wasn’t but, as she was involved in rescuing the cygnets, I guessed she was someone official, perhaps from the RSPCA? Looking at the mended bridge suddenly didn’t seem very important but there was obviously nothing I could do to help and I didn’t want to get in the way so I left Sue trying to coax the cygnet out of the water with swan food.

As I rounded the pond, heading towards Rollesbrook and the bridge, I looked sadly down into the water. It really did look very green and there was some kind of unpleasant scum floating on it. It almost looked as if it was fermenting. Was there really paint in the water or was it algae? Either way things didn’t look good at all.

Just as I’d been told, the little railway sleeper bridge had been repaired but somehow, thinking about the lake, I couldn’t really find much joy in this. Originally I’d been planning to walk through the Beyond Graffiti tunnel and then head around the outside of the Common back to the parkrun finish to get some steps in for my Million Steps Challenge. Talking to Sue meant I no longer had time for this. Besides, I couldn’t stop thinking about the lake and the swans so, after a couple of quick photos, I headed back.

When I approached the lake I could see that Ian’s truck and the Environmental Health car had both gone but Sue was still trying to coax the cygnet out of the water. This time I decided to walk around the opposite side of the lake and see if I could see where the paint had been poured in. The further I went the worse the water looked. Hundreds of tiny fish had come to the surface. They were alive but seemed to be struggling to breathe. Until then I hadn’t even realised there were fish in the lake but it didn’t look as if they’d survive very long unless someone did something fast.

When I reached the south west corner of the lake I finally saw something that looked very much like pale blue paint floating on the water. There was also a strong chemical smell hanging in the air. Thankfully the swans and the remaining cygnet were now on the other side, well away from the danger. There were a couple of forlorn looking ducks and a clutch of ducklings on the bank.

Very quietly and carefully, so as not to scare them, I stooped to take photographs. Then, afraid the birds would jump into the contaminated water, I cooed and clucked and tried to coax them away from the edge. They were having none of it though. The whole thing made me want to cry.

Just the other side of the scummy paint, or whatever it was, Sue was still desperately trying to coax the cygnet out of the water but having no more success than I had had with the ducks and ducklings.

We spoke again briefly. She asked me if I would post some of my photographs on Facebook along with a warning to dog walkers to keep their pets out of the lake. It seemed a small thing to do so I said I would. Then I headed sadly back towards the parkrun finish.

When parkrun was over and we were heading back towards the Bellemoor for coffee, I saw Ian standing by the gate talking to Pete, the keeper of the parkrun PA system. Of course I stopped to chat and ask about the situation with the lake.

It turns out, what Sue was convinced was paint, really was algae. The Environmental Health people had taken water samples to be analysed and were sure it was a blue green algal bloom caused by the unusually hot weather. This algae, which is actually a bacteria called Cyanobacteria, is found in small quantities in almost every body of water, in soil and even living in the fur of sloths. It is not normally a problem but, with the right conditions, still water and hot weather, it can form large blooms which resemble blue green paint. Worryingly, in this state, it becomes highly toxic, not only to wildlife but also to humans.

Ian wasn’t sure what could be done about the algae. Draining the lake wasn’t an option as the algal bloom could get into Rollesbrook and from there into the other lakes. He was going to put up temporary fencing and signs and see if the Environmental Health office had any other suggestions. The poor sick cygnet was in his garden at Holly Lodge and was waiting for the RSPCA to come and look at it. He was hoping they would also be able to catch the other cygnet and the adult swans. While I was relieved it wasn’t paint dropped into the lake by vandals, it still didn’t sound like good news at all.

Please see my copyright information before you copy or use any of the above words or pictures. If you’re worried about privacy or data protection, please see my privacy policy here.

12 thoughts on “Blue green algae”

  1. A revealing story. Best not to post it on FB for fear that it might give some idiot the idea to dump paint into that old, and for me memory filled, boating lake. Let’s hope the water treatment people can assist here and improve the water quality for the ducks, swans and fish Marie.
    Steve Davis,

    1. I think the very warm humid summer has caused this algal seems to be happening all over the country. So sad for the wildlife though.

  2. All pond keepers suffer with this problem every year there is good Sun,light,and fish,or,Wildlife,which feeds it.Pond keepers keep it under control by constant raking.Unfortunately,large tracts of water don’t get the attention needed.It must be constantly controlled.

    1. Interesting. As far as I know the boating lake hasn’t had this problem before but I’d imagine it would be impossible to rake it because of the size.

  3. I know that blue green algae can be deadly to dogs and can kill them very quickly if they ingest it. It sometimes appears on the water of forest ponds though I haven’t yet come across it this year.

  4. Marie, I am editor of an online newsletter (Southern Finnish Lapphund Society) and I would like to put a warning about Blue Green Algae in our next issue. Would you give permission for me to use one of your photos?

    1. Of course. It would be nice if you could credit the blog but go ahead. The BBC used them too for their news item about the algae outbreaks.

Why not tell me what you think?

This site uses Akismet to reduce spam. Learn how your comment data is processed.