River Nadder Invertebrates Survey field trip

Lampreys Tiit Hunt, CC BY-SA 3.0 httpscreativecommons.orglicensesby-sa3.0, via Wikimedia Commons

Well, some of us were brought up on King Henry 1 having died of a 'surfeit of lampreys', but I doubt anyone thought they (if they had any idea what 'they' were) could be found in our very own Nadder.  However, it was Henry who probably 'defined' Clarendon Park, just the other side of Salisbury, and built the Hunting Lodge there - apparently out of Tisbury stone.  So maybe it was Nadder lampreys he died of!

This was a great opportunity to see the myriad forms of life that exist in our local river - including, as it turned out, lampreys - under the expert leadership of David Holroyd who is Membership Secretary Teffont Fishing Club and River Monitoring Coordinator for Salisbury and District Angling Club. ​

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As with our Harvest Mice Nest survey, there was a serious side to this.  David explains that river quality and wildlife is deteriorating at an accelerating rate. This is particularly so in Wiltshire and Hampshire where 95% of the planet’s ‘Chalk stream habitat’ is located - strictly speaking the Nadder isn't itself a chalk stream although very similar. Because of the threat of continued deterioration and its unique nature and biodiversity, the whole of the River Avon and its four tributaries are designated a SSSI and subject to the status of being a ‘Special Area for Conservation’.

David led members including Izzy Fry and other members of our Young Nature Watch group, to a favourite stretch of river, just outside Teffont Evias, where he collected samples from the river and brought them it to the bank for examination close-up in a sampling tray.  As well as the lampreys and a number of insects, there were also brown trout, grayling, chub, dace and minnow.  David says that the Nadder is currently in good health and being monitored throughout its length. 

This is especially important as the Nadder is also a key spawning habitat for the Avon Salmon, which is particularly endangered - and indeed, excitingly, salmon parr were also found. David's full account and list of sightings is here and there's an excellent account of the life-cycle of salmon here.

Andrew Graham said how fascinating – and surprising – it was to discover the wide variety of insects that give life to our rivers.  He added,  'I have never seen a lamprey before and it opened my eyes to how much is going on in the Nadder, which to my ill-informed eyes, has always looked a bit uninteresting going through the village...' 

​Certainly, to judge by these photos, a great time seems to have been had, as they say, by all.  Great weather, too.​