The sidescan kit

I well remember one session on Ardleigh Reservoir, having used the NASA to locate the feature and depths I wished to fish and having lowered the mud weights, I started tackling up only to be disturbed by the bleeping from the NASA which I had forgotten to turn off. What was strange was the only item that bleeps on these sounders are the depth alarms, which indicate minimum and maximum settings, used by me to indicate significant changes in depth, e.g. bars or spits under the surface. There were certainly none of these in the 27 ft of water and it was the minimum depth warning which was set at about 20 ft that was bleeping, watching the spinner indicated that there was the occasional object moving about beneath the boat, which were surely fish. Being there for the pike I turned the sounder off and got on with tackling up and getting baits out.

A couple of hours passed and with just a couple of small pike coming to the boat I wondered if those ‘fish’ were still there? As soon as I turned the sounder on ‘bleep’, bleep’, sure enough they were. To cut the story short I searched through my tackle for bits appropriate to fishing for what I suspected might be perch and was soon ‘twitching’ a small chrome spoon beneath the boat and it was not long before I got a fish hit the spoon on an upward pull, this perch weighed a couple of ounces under 2 lbs and over the following couple of hours I almost forgot the pike and fished for these perch (pic), taking several more to 2.5 lbs. The lesson was well learnt and on successive trips this phenomena was to be observed and on several trips friends were to catch fish to 4 lbs plus by dropping small lures to the bottom and ‘perking’ for perch.

A new dawn.

I mentioned earlier my lust for knowledge when it came to my fishing and thoroughly enjoyed using the NASA thanks to events like the one related above, but information was filtering into angling about more sophisticated sonar devices that gave greater detail of the bottom, weed and snags and more importantly, identifying fish. Our past President Colin Dyson as editor of Coarse Angler went into great details on his exploits with, if my memory serves me, a Lowrance graph recording sonar, if it wasn't a Lowrance it could have been an Eagle. Whichever, this got my juices bubbling and when an offer came to obtain a Hummingbird 4 ID at an attractive discount I could not resist and was soon indulging in the benefits of the data presented and learning so much more about the places I fished.

The scan head

It must come as no surprise that I started to discover a whole new set of facts about these places and more importantly I could now distinguish much more easily what was weed and what were fish, in fact the ‘ID’ model of the Hummingbird would screech out its sounder at the merest hint of a swim bladder and visually display them as a red dot on the screen, it would further indicate the size of the fish by displaying the red dot over a black dot for bigger specimens. The pictures here show a snap shot of what I was seeing on the screen, telling me about roach and bream shoals I was to find on fisheries I was fishing. Let me say this now, no echo sounder, no matter how sophisticated, will actually catch you any more fish, what it will do however, is help you locate their likely haunts, their prey and very occasionally the fish you seek, but this will only help in location, not guarantee you catching them!

On many of the waters it became clear that where as in the warmer months shoals of roach and bream were to be found all over the fishery, this was very different in the winter months. Large shoals of coarse prey fish will annually congregate in feature areas in extreme cold weather, leaving 99% of the reservoir devoid of little more than small shoals of fry and perch. Most of the pike being caught, coming from in and around the area frequented by this huge shoal of bream and roach. Discovered in one area was a large underwater feature close to a deep channel varying from 25 to 28 ft dependant of reservoir levels. With so many prey fish to feed on the pike could at times prove difficult to tempt! However on a good day the sport could be absolutely brilliant.

Most of the use of echo sounders has related to waters in excess of 20 ft in depth, whilst these are the waters I originally required the sounders for, I have learned to make use of the Hummingbird on shallow waters and in fact on any water, even if I cannot use a boat. One of the shallow waters is a mere near my home where the depths do not exceed 6 ft at the deepest but where the use of this method has brought its rewards with some super catches of zander, after locating the fry shoals, fishing from a boat!

Until you use a echo sounder or sonar you will probably not expect and believe what you see, invariably no fish, particularly in waters shallower than 15 to 20 ft deep. In waters less than 10 ft deep there is seemingly no practical advantage to using a sounder for anything other than depth sounding, that is if you accept the gospel according to the manufacturers and regular users.