Apologies for the loss of last week's Bioblog. I tried to delete a duplicated photograph that I put on Thursday's entry, but it deleted the whole article !

Monday 16th June : On leave

Tuesday 17th June: Most of the day drawing up a report on a Lamprey investigation we carried out for Scottish Water on the Meggat, just below the dam, on Friday.  What has happened is that with the flow of the Meggat itself being  regulated by the dam and it not therefore having large floods any more, a delta of boulders has been created in its channel where the Glengaber burn joins it. This has ponded back the water so that the gauging weir that is supposed to measure the compensation flows released from the Meggat Reservoir is under about half a metre of water and is unusable. To get it back into use, the delta has to be removed, and the ordinary requirement for such work is that it be done outside the period when there are Salmon eggs in the gravel (October to April) so that redds are not damaged. However, the Tweed is also a Special Area of Conservation (SAC) for Lamprey and SEPA raised the question as to their presence in the area - which we were unable to answer for Scottish Water, not having sampled for Lamprey nearer than the mouth of the Meggat in St. Mary's Loch (where they are present). While Lamprey larvae are very widespread within the catchment, their numbers are usually at very low levels, with only the occasional hot-spot in prime habitat and it is difficult to predict where such spots might occur. There was nothing for it therefore but to turn out to look. To my great surprise, the very unpromising looking habitat - no sand or silt at all - turned out to have relatively good numbers of larvae, presumably because of the slack water. I had not come across a site before where  suitable conditions for Lamprey larvae were created solely by slow water flows without any fine sediments being visible at all. Consequently, I lost my bet to Barry that there would be no larvae to be found and now owe him a "substantial" meal -whatever "substantial" may mean ( a large plate of porridge is a "substantial" meal, for example)

A trout of about 1lb brought in from Boleside that had been found moribund there yesterday - proved to have had well developed Furunculosis. Was in very good condition, so not clear why it should have succumbed - although the river is low, the water is not unduly warm.

Wednesday 18th June: A day in the office, doing masses of little things and sorting out all sorts of e-mails that needed answering. Read scales from a 9lb 15oz Sea-trout caught on the 21st May - a Maiden fish, and only 1 winter at sea. A draft report in on the thin Grilse of 2006 which showed how extreme some of the weights had been, though in the context of the general decrease in sizes that has been going on since the 1950's, the significance of the episode is uncertain. Comments in, at last, on the work packages I drafted for the North Sea Sea-trout programme & so found out what bits I'd missed putting in.

Thursday 19th June:  A large document in from SEPA about funding for restoration of freshwaters and coastal areas. This is all part of the Water Framework Directive process by which all water bodies in the EU are being classified into five grades. All waters not making the top two grades have to have plans established for bringing them up into these two top classes. The "characterisation" process has been underway for a couple of years now, to rank each water course and loch into one of these five grades and we have been assisting in the process with our data on fish. Restoring waters to improve their grades is the next step and this document is the beginning of it. As "connectivity" is one of the factors that has to be considered in grading water courses, easing obstacles to fish migration can be funded under these proposals. Creation of buffer zones, wetlands and quite a range of activities as well. SEPA is not looking to do such work itself, but will fund others to do this so we are having to consider what we would like to see done here and how it might fit. In the evening, out with Kenny and some of the Earlston Angling Club to do some main channel electric-fishing on the Leader to find takeable-sized trout for scale collection. Though the water is low, it is really too wide to be effective and we see big Grayling breaking back past us - also, we lose the biggest trout we see, about a lb. Get 8 takeable trout for scales and more just under size.

Friday 20th June: More proposals to study come in, this time from RAFTS about the genetic mapping of Scottish salmon populations. This has been in gestation for some time, and is now taking shape. Essentially, it is now known that within even quite small river systems there are numbers of distinctive salmon populations that seldom interbreed. Even where there are no physical barriers such as lochs or waterfalls to break up spawning areas into distinct units, separate populations can be found with ranges of about 5kms or so. We have the genetic mapping of Tweed salmon as one of our management priorities as we need to know which parts of the river produce which types of fish - where do Spring, Summer and Autumn salmon come from ? Once we can map the juvenile populations we can take samples from adult fish caught in the estuary at different times of year and so link them to a juvenile population and thereby find out what sort of fish those juveniles become. All our electric-fishing sites which, at the moment, just give information on juveniles in general, will be able to be categorized in future as being "Spring", "Summer" or "Autumn" juvenile sites. Juvenile strengths can then be matched with adult population strengths and allow greatly improved management of the river. It will be a huge step forward and will transform salmon management in Scotland as a whole.