Autumn surveys continue.

No longer can we call our field work ‘summer surveys’ as the beginning of September saw us officially enter into autumn – a slightly depressing though as only a minute ago it seemed like we were in spring with the rest of the year still ahead of us. But as the nights draw in and the countryside changes from verdant greens to yellows and oranges there can be no doubt about the season. As ever water levels are the greatest hinderance to completing our programme of works for the year and as the years draws on weather becomes less and less predictable. On a side note there are two beginnings to autumn; meteorological autumn and astronomical autumn. Meteorological autumn uses a set date (September 1st) for ease and astronomical definition is based on Earth’s orbit around the sun and the autumn equinox, which marks nearly equal day and night.

Last week Ian and I continued to progress with our monitoring of Arecleoch and Chirmorie Windfarms with surveys across the upper Duisk Catchment. These are always interesting and have a mixture of trout, salmon and eels depending upon the watercourse and the accessibility of the burns. The Cross Water has a fantastic waterfall a short distance upstream of Barrhill that prevents salmon and trout migration but doesn’t hold eels back – see image below. The Stinchar catchment as a whole seems to perform very well for eels relative to other Ayrshire watercourse primarily due to the lack of manmade obstacles in the form of dams and weirs. We still find relatively good numbers of eels beyond the Linn Dhu falls which highlights just how incredible eels are at finding their way over obstacles such as this – no doubt the grippy wet moss helps them negotiate these falls and access the plentiful supply of good quality habitat beyond here.

 

On the Cross Water site at Martyrs Tomb we had a number of salmon fry which was encouraging as in 2024 we only recorded salmon parr – this year salmon fry numbers in the Duisk catchment have been very good with some of the highest densities we’ve seen in this catchment during our timed surveys. Salmon can access as far as Lochton Mill on the Duisk catchment before another waterfall halts their progress although anecdotal evidence would suggest that historically fish did make it beyond this waterfall. With less fish returning to our rivers there is less of a driver for salmon to push beyond these difficult obstacles to find unused habitat.