Although there has been an increase in the number of moors which have reported incidences of Bulgy Eye this season, it certainly does not appear to be the case that the disease has “exploded”.
Instead what seems to have happened is that gradually more and more Moors are being infected, but in the main, not to any large extent. The maximum percentage of infected birds found on Shoot days seems to be below 20%, with very rare incidences of this increasing to nearer 30%, but even on those Moors with high numbers of diseased birds found, the numbers infected drop back quite quickly as the season progressed. What we do not know is how many grouse which are affected do not show visible signs of the disease and therefore look “clean” to the naked eye.
Swaledale and Hexhamshire Common areas all showed increases in Bulgy Eye numbers and this season seems to confirm the fact that higher wetter moors with large grouse populations are in the main the worst affected. Despite having high numbers of grouse, few of the dryer moors seem either to have it at all or if they do, to have it on any scale. Although its spread in the North of England has continued, with Coverdale Moors now finding some diseased birds, apart from one or two more moors in the Lammermuirs which experienced it for the first time last season, there doesn’t appear to have been a spread to any other moorland areas in Scotland. The disease remains Lammermuirs centred in Scotland for the time being.
It was interesting to see that a number of moors that have not been infected did take their bio-security seriously for the first time this year and generally all Guns seemed to go with the spirit of trying to prevent the spread of this very unwelcome disease. Cleaning shoot equipment, boots and car wheels is relatively easy, but it is impossible to clean your dog effectively, so the only answer is to leave your dog behind after he or she has been out on an infected moor or a moor in an infected area. Although there doesn’t seem to be any hard and fast rule, it seems likely that if a dog was carrying peat grouse droppings or any other material which contains Bulgy Eye, about a week between it going on an infected and then going on a non-infected moor should be enough to prevent the spread. However, this is no more than a best guess.
It seems likely going forwards that Bulgy Eye will continue to bubble away in the background and probably will spread to many, if not all, the currently uninfected moors over a period of time, particularly in the North of England. Scotland may fare somewhat better given the greater scale of the moorland areas and the remoteness of much of it. Whilst we know very little about it, we do know that continual high densities of grouse are if not the cause, certainly a common factor (these do not necessarily need to be on one specific moor but can instead be in a close moorland area) and if Moor owners and keepers are wanting to be fairly sure not to have it or if they do have it, to reduce its effects, then reducing the stock down certainly appears to work. It seems from the experience of certain moors in West Northumberland which had it right at the beginning of the outbreak (2010), that there is a threshold below which whilst the disease may continue to be present, it does not manifest itself in any significant way. We do not yet know what that threshold is, but once grouse numbers get to that threshold and particularly in the second year of a rise in grouse numbers, then Bulgy Eye seems to roar away. Below that, it does not “prosper”. The best advice continues to be to not carry too much stock for too long, but to allow your stock levels to vary, so as to deny the host in which the disease needs to thrive.
Although there are reports of worm burdens increasing on some moors, overall, worm densities again seem to be quite low going into the winter, despite it being one of the best grouse years in living memory. It certainly looks good for 2015 assuming the winter and spring play their part!
William Powell Sporting