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A Tweed Fisheries Biologist’s Week – Saturday 6th June

Saturday 6th June: Down to Paxton House for the first exploitation netting of the year. We've long being doing this in September, just after the netting season finishes, but are now trying to see what the exploitation rate is earlier in the year. For the September fish, less than ten per cent of our tagged Salmon are caught upstream by anglers (which should be the rate for all the fish at that time) but earlier in the year, the proportion caught is presumably higher.  Find a small audience at the netting station – the event has been publicised by Paxton House as well as ourselves, but nothing for anyone to see to begin with – 4 shots of the net with nothing, then a couple of Sea-trout, then 3 more shots with nothing and then, as the flood tide has its full effect, two reasonable shots. End up catching eight Sea-trout and three Salmon. One of the Sea-trout must have been close to 10lbs. All in good condition, the Sea-trout particularly so. One of the Salmon very much fitted the description of a “June Jumper”, a traditional netsmen's term for June fish, being lean and with a large tail.

Monday 7th June: Out with Barry to do a lamprey survey on the lower Gala where engineering works for the Waverley railway are to be carried out. Having done a lamprey survey of the whole Gala in 2004 when found it to be full of larvae from top to bottom, was expecting to find lots at these sites, which turned out to be the case. Caught nearly 200 in one sample. While working here, had a visit from an old post-graduate colleague from my days at Otago University (NZ) in the 1970's. He's been Chief Executive of the Fish and Game Council of NZ ( = the ASFB & the various shooting organisations here + statutory responsibilites for salmonid fishing) since graduation. Catch up on all sorts of news while getting on  with the sampling. Anyone who knows anything about the NZ environment  finds the sort of advertisments put out here distinctly amusing: the “Free Range Cows” advert for Anchor Butter, for instance. This gives an impression of “clean and green” – but in NZ, the Fish & Game Council ran a campaign called “Dirty Dairy” to highlight the devastation caused to rivers by intensive dairying – the pollution  by run-off from heavily grazed, fertilised and manured land and, in particular, the de-watering of rivers to irrigate pasture land for dairy cows. I hadn't heard much about this last before – but now hear that irrigation is increasingly used by dairy farms, with massive centre-pivot systems up to 800m long, that rotate over whole sets of fields, where the fences are of a type that can be run-over by the pivot wheels and then rise up again. The other NZ advert that amuses is the general tourist one about “100% Natural” – actually, NZ is the world's worst case of devastation by alien species. In the 19th and early 20th centuries, there were “Acclimatisation Societies” whose aim was to bring in and release any animal or bird  thought useful or decorative, and species were brought in from all around the world. I can remember as a student going up vantage points in lowland NZ and looking around to see if I could see a single native plant or animal – and in most cases, I could not. Every blade of grass, bush, tree, bird  I could see was an alien from some other part of the planet. Even in the bush in the mountains, the most likely bird to see is a Chaffinch !

Tuesday 9th June: Out with Barry again, this time to do more work on the Bullhead population near Ashkirk, an unwelcome alien species here. Find that it has extended its range downstream by at least 100m since last year, and possibly further, as still finding them when finished. Will keep on working downstream till find the new edge to the population and then will try and remove them from the newly colonised areas at least and so keep a lid on them till some long-term solution can be found. Kenny at TweedStart, James at a meeting to draw up a protocol for dealing with Signal Crayfish.

Wednesday 10th June: Spend the morning with a visiting statistician from FRS, showing him our historical catch data which could be useful for long-term analyses of Salmon trends. In the afternoon start putting together a draft response to the Water Framework Directive,s SolwayTweed River Basin Management Plan.

Thursday 11th June: All day drafting a response to the consulation on the Tweed Area Management Plan of the SolwayTweed River Basin District of the EU Water Framework Directive.

Friday 12th June: A full scale mobilisation and down to Coldstream to net the river along with members of the Coldstream Angling Association. This was also our Benefactors' Day, so an interested audience on the bank as well. The netting went well, but only one large fish, a 73.5cms Eel – last time we did this bit, we had good numbers of large Grayling and some good trout as well. This part of the river is notorious for its large trout and has been fishing well this season so the fact we didn't catch any suggests they just got out of our way. No Sea-trout either despite reports of a catch of 300 on Monday night at one of the netting stations.  Good numbers of smaller fish, mainly Salmon Parr, some of which were pretty obviously still smolts, and 6″-7″ trout. Also Grayling fry of around 60mm in length. In all, 183 fish. As we also needed a genetics sample from this part of the river, went in with the electric-fishing gear afterwards. A very different sort of technique here, compared to the usual burns. Here I had to spot the Salmon fry spaced out in their little territories and put the Anode on top of them to catch them – there's so much space in this sort of place on the big river they otherwise detect the electricity coming and clear off before they can be caught. Interestingly, these fry were smaller than those I was electric-fishing earlier this week near Ashkirk – perhaps a sign of later spawning in this downstream area. Also electric-fished some of the shoals of little fish visible along the bankside and found that they were not Baggies but Grayling fry. This is the first time I've actually seen shoals of Grayling fry and they do look a bit like the usual Baggies you see shoaling on the edge of the banks, so I'll have to look more closely in future. A good lunch with the Benefactors afterwards.

On leave next week