Bogton Loch beside Dalmellington was one place I’d never really visited until today. Of course I’d seen it and walked around some of it in the past, but I had no idea of depths or the really anything else other than it has a reasonably large pike population and some of then run to a large size. With permission from the owner we headed to the loch around lunchtime. I was interested to look at where the river enters the loch, particularly to see the weed beds in the margins at that point as I wondered if it may be a great ambush point for pike to predate smolts as they descend during their spring migration.
Armed with a depth sounder and the inflatable boat, Muir and I headed there for a few hours today to see what we could see. Now just by chance I had a wee spinning rod and a few small lures in the van so we took this with us too.
Muir getting the boat ready beside Bogton Loch at Dalmellington.
Almost immediately it was obvious that there was no depth to the loch. The sounder struggled to fix to bottom it was that shallow and I estimate the large majority of the loch is between 3 and 4 feet deep. We only found one point along the south western shore where the depth reached 5-6 feet and a small area on the other side. Much of the bottom was sandy/silt with a carpet of weed over it. Lilly pads have just reached the surface and many more are soon to appear. I don’t think I’ve ever seen as many beer cans dumped into a loch as I saw there today. Take your litter home with you!
The sounder quickly revealed that Bogton Loch was very shallow indeed. I hadn’t expected it to be deep but neither did I expect it to be so uniformly shallow. Th image shows the loch to be 2.2ft deep but you have to add on another foot to account for the transducer sitting below the surface on the transom.
The weedy margings were mainly along the souther shore but they didn’t encroach near the river mouth or outfall and I expect smolts will very quickly pass through the loch although undoubtedly some will disappear down the throats of the pike in the loch but hopefully not too many. It would be an interesting exercise to try a smolt trap upstream on the river and downstream of the outfall to see what percentage are lost.
There were 7 or 8 swans on the loch and a few ducks but we kept an eye out for the osprey from Loch Doon appearing but unfortunately it didn’t. We watched for rising trout but didn’t see any and I expect that they will be few and far between preferring the relative safety of the river to the dangers of the loch. We decided to spin a lure for a while to see what we could catch and failed. I expected to pick up a pike, a perch or two and and possibly even a trout but no. A couple of pike followed the lure to the side of the boat typically turning away at the last moment and eventually we managed to hook a small jack as we headed in but it dropped off right at the boat.
It was a nice day to be out on the water and at least we answered the questions we had but as ever, that raises more but they will keep for the time being. The inflatable is proving very handy and we purchased this though the CIRB Invasives project before it finished to allow us to continue controlling Giant hogweed in difficult to reach places on the River Ayr but it is proving to be very useful for other things too.
There’s not as many pike in the bogton as there used to be, we used to go down when we were boys and catch 5 or 6 a night, but I go down with my boy now and again and only get the odd jack or 2. Maybe it’s to do with the otters on the loch they come out like clockwork just before it gets dark. One went for my boys popper last year n i grabbed the rod off him and brought it in as quick as I could. Fished it for years and never heard or seen a trout caught in it but the river both sides of it has trout. There’s been a few big perch out of it my mate got a 4 punner one night. I agree the litter is a disgrace.
Thanks Colin. I didn’t reckon there were as many pike as I expected or else I would have nabbed a few jacks at least. I also half expected a lot of wee perch but they failed to show. I’m sure otters can’t be responsible for clearing it out too much but I suppose anything’s possible. Perhaps angling pressure is partly responsible too and handling larger pike can certainly cause them problems if not done with due care. They are more fragile than many people imagine.
Angling pressure is actually quite low on the bogton, it probably doesn’t look that way by the amount of rubbish but it’s always been like that. There’s definitely more otters than there used to be, in the bogton and up andvdown the doon from the Ness glen to waterside. I fished down there regularly when I was a boy and never saw any then maybe abt 15 years ago I saw my first otter and since then saw them loads of times in the loch and river but I don’t know if that has to do with lower pike numbers because I am no expert. And also myself and the nosy that do fish it always release the pike. I am not complaining though because it gives the smooth n parr a better a chance of survival. Very few perch in it I have only saw a couple of big ones out of it, think it’s just pike eating pike.
I meant smolts not smooth and boys not nosy. Darn predictive texting.
Stuart
You might like to compare your survey with this one completed in 1906
http://maps.nls.uk/view/74400504
The National Library have I think the whole series on line here
http://maps.nls.uk/bathymetric/index.html
They have of course to be treated with care, where loch have been impounded since the survey (Loch Doon being the obvious local case in point) and perhaps where other factors are at play such as mining subsidence.
G
We have compared the results and they are very similar. The loch has shallowed near the inflow in recent years it seems and a new island is forming. I have always found the old bathymetric surveys to be reasonably accurate but due to the simple method of recording using plumb lines on transects, they often missed features. Modern soar allows greater accuracy and confidence that important features aren’t missed.