Bruce Payne shares the delights of crayfish-surveying…

During 2018 I had the great pleasure of working with the project team and numerous volunteers on the Culm Community Crayfish project. This project was part of a long-term initiative to safeguard the River Culm’s white-clawed crayfish by capturing important information about populations of both the native and non-native species of crayfish in the River Culm and its tributaries. You can find lots of really interesting information about crayfish, the set up of the many faceted project and what it achieved on the Blackdown Hills AONB website.

There was a massive range of activities that volunteers engaged in across the project but this note concerns the survey activity in the river, the setting of refuge traps, checking them for crayfish at regular intervals and recording our findings. It should be noted that to enable this activity the project team had done an immense amount of pre-work, identifying potential sites, mapping them, securing landowner agreement for access and then running the essential training sessions for volunteers.

What I hope to do here is give you a flavour of my experiences as a member of a survey team, the types of people I met, the things we did, what we learnt, places visited and the fun we had. Oh, and most importantly we did find some native crayfish, and here is one!

A close up of a hand holding a crayfish

Close-up with a white-claw

For all those involved there was a lot of joy in the sharing of new experiences, new acquaintances, new locations and I can recall some excellent picnics in idyllic settings

I spent about 40 days across the summer of 2018 surveying the Culm and its tributaries working with lots of folk from different backgrounds and not only local people. Not surprisingly everyone shared an interest in caring for the environment but from a variety of perspectives. These ranged from retired locals living in and having a care for the Blackdowns, like myself, pre- and post-graduates seeking a career in research or ecological consulting and people from various organisations either partners or on a day’s environmental leave.

Our survey days would start at about 10 meeting in the AONB team office where we would, depending on numbers, organise ourselves into teams of 4/5 and receive information and maps of the survey sites. Each site would be a stretch of the Culm or one of its tributaries where our job was to either set refuge traps at agreed intervals, check those previously set or retrieve them at the end of the survey. We would then get ourselves kitted out with traps (if they were to be set) waders, buckets and various other bits and pieces before heading off to the site.

Once on the road the first challenge was to locate the site and find suitable parking. Neither necessarily easy and on occasion we would need to drop folk off with the gear or perhaps haul the kit across fields to get to the starting point. As many of the sites were on private land we found some fascinating stretches that you wouldn’t otherwise see, but it also meant that negotiating the banks and river could be a little challenging and we soon developed new skills in negotiating the barbed wire to be found in abundance and occasionally in the river! Rambling with intent!

Before touching on the setting and checking of traps best to explain what they look like: think panpipes and you will get the picture, a series of eight tubes about 20cm long of varying diameter, 4-8cm, mounted on a metal backing. Hauling bags of these along the bank was in itself a challenge. A trap was set by placing it in the river, but was it really that simple? It soon became clear that there were quite a few tips and tricks to bear in mind – is the river deep enough but not too deep at this point? The trap needs to be tied to something on the bank – what’s available? It needs to be held down on the riverbed, is there a large rock available? How will I find it again? Ah, we describe its location on our record sheet and that’s also why we’ve brought strips of hazard tape to mark its location. So that was easy!

Now returning to check or retrieve traps you would think should be easier, locating them must be straight forward, we’ve marked them on a map, we’ve tied a strip of hazard tape nearby and you must be able to spot where they are tied to the bank. But due to changes in vegetation, through growth or cattle movement this often became a tricky and time-consuming task when the tape has gone missing and an occasional trap has been washed downstream after heavy rain. There was often a lot of to-ing and fro-ing accompanied by shouts of ‘have you found it yet?’

A volunteer in waders holding a crayfish and smiling

Bruce, happy to have found one of the elusive white-claws!

So, we eventually locate the trap and check it by emptying the contents into a bucket… and is there a crayfish? You need to look twice in the pipes as the smart ones would hang on in there trying to look insignificant. We had been briefed on identification and recording findings and invariably one of the team would be well qualified in this. As mentioned above the detailed results of our findings can be found on the AONB website. We did find a lot of crayfish but as expected we mostly found the invasive species with a few pockets of the native species. The latter findings were always met with great jubilation!

Working in the river there was no shortage of trip hazards and manoeuvring in waders is not the easiest of activities. I think I’m right in saying that I hold the record for the number of duckings (2), though only one witnessed at first hand which minimised my embarrassment. I believe there were 3 runners-up with one each to their name.

What I have described may not sound like a lot of fun but I believe for all those involved there was a lot of joy in the sharing of new experiences, new acquaintances, new locations and I can recall some excellent picnics in idyllic settings. Above all the many volunteers that I worked with had the satisfaction of knowing that they had contributed to an important part of the overall project.

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