28 July 2022

Fieldwork in the Dee Estuary

Your research is only as good as your samples allow it to be! So for a project all about foraminifera analyses, getting samples is important. For my project with my student Alexander, the idea was to compare foraminifera assemblages from the Dee estuary (with her highly industrialised catchment) with those from the Cefni estuary (with much less industrialised catchment). So we needed to visit both locations. And I wanted to start with the Dee. It's a lot further away, it's a lot bigger, and I know it less well. It is easier to adjust what we do in the Cefni to what we do in the Dee than the other way around! And it had taken Alexander a bit of a while to come up with a sampling strategy, but once we had it, we could go. I made sure to book the GPS and a School vehicle. And one rather overcast Friday morning I picked up Alexander from main campus!

I had checked the route beforehand; it shouldn't be too difficult. Just head for Manchester until you see Birkenhead indicated, and then go left twice. That's it! And it really was that simple; just on memory, I got to where we needed to be. And there happened to be a pub there.

I looked at the endless Saltmarsh with its complete absence of shelter, and as my student I barely knew, then I thought maybe we wanted to pop in for a coffee so we could also use the facilities. Having a wee in a saltmarsh with a stranger not very far away is not everybody's idea of fun. So we had a quick beverage in the pub! And then we started the GPS. We were go!

Right by the pub there were actual stairs leading onto the marsh. We took them. It didn't lead to a path, though. The vegetation (mainly sea club rush) was almost as high as we were, and the going was tough! And within 10 m we were standing in the slop. I was glad I had warned Alexander beforehand.

Decorative Parkgate at the head of the marsh

Soon we took our first sample. And got ourselves a GPS location. And then we were on a roll. The one thing that worried me a bit, though, was that the going was slow and the marsh is big and I absolutely did not want to be chased out of the estuary by the tide. Soon I was evaluating scenarios in my head. Scenario one: get all the way onto the sandflat and back in all is well. Not very likely. Scenario two: sample the high and mid-marsh and come back next week to sample the mudflat and sandflat. And then park the car somewhere where you can get to these places without first having to walk over several kilometres of vegetated marsh. Scenario three: sample mud and sand in a big channel and hope for the best.

Big channel

When you are on a saltmarsh, you end up having to cross tidal channels. That slows you down! I have done it many times before, but it still takes time, and Alexander sometimes spent a bit more time looking for a good place to cross. I suppose that's fair; he weighs more than me, so has a higher risk of sinking down deep and getting stuck. But we got a good routine going with me crossing first, taking over the GPS, and him then following. And we were making good progress, but time was ticking away.

I settled for scenario three in the end. It's not ideal, but safety first! I don't say that sort of thing very often, but one doesn't mess with the tide without regretting it. And if push comes to shove we can always tack scenario two on at the end.

Without any scary incidence we got back to the high marsh. We seemed to have found an easier route back, a bit further two the west. But it was too good to be true; at some point we hit a channel. And it looked too deep to cross. We then had to follow it back east to cross it where it was barely existing; that was the exact place where we had crossed it on the way out. But following that channel was hard work; we were again in the person-high vegetation. But what can you do! We had to get back.

Trying to get back through the Sea Club Rush

When we got back to the car we tidied up the GPS and then went into the pub for another beverage, and the opportunity to change in the toilets. And then we could accept the way back! Luckily I found it easy to find my way back. And once on the motorway things got a bit slow; there was a broken-down vehicle that had caused big traffic queues. But we got back to campus in the end. It was already beyond office hours for the technical staff, so I just put the GPS in my own office. Nobody would be needing it over the weekend! And then I could go home. Not a perfect day in the field, but good enough. And next week we’ll be doing the Cefni! 

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