Eels in Urquhart Bay, Loch Ness
Still frame from video recording
The new tv camera has been tested down to 80 metres in Urquhart Bay and near Urquhart Castle over the past week and the new arrangement of lights is now producing the best image quality and visual range ever. In less than ideal circumstances some really interesting footage of unusual eel behaviour has been recorded, together with some educational encounters with less animate denizens of the bay.It seems the field of view in many shots is at least 3 metres ( 10 ft) wide, and fish over 4 metres (13 ft) away can be seen.
The Lowrance Bluewater 200M sonar unit on loan from Richard Carter performs far beyond expectations. The original cable some 6m (20 ft) long was chopped off and replaced with 100 metres of RG59 co-axial cable. There is naturally some loss of performance but we can still receive signals back from objects over 20 metres ( 66 ft) in front of the transducer.
The horizontal element in the tail fin performs its design function in tipping the unit "nose down" as it is lowered to the bottom, causing the loch bed to appear on the sonar display screen well before it comes into visual range. Once on the bottom, the unit levels out and the sonar then acts as a "look ahead" or "forward search sonar" giving excellent warning of submerged trees and other dangers. It seems to have no effect on fish - they behave the same way whether it is switched on or not. Future experiments are planned to explore the deployment of the equipment from a "dead ship" - i.e. one with no engine running, and also using infra-red illumination which was in use when we had the best encounters with "vertical eels".
Here are a few stills from the video
record. Anyone wishing to have copies of the video tapes for private study
should contact me.
Has this been observed before?
The following three frames show a group of eels which
were vertical in the water when first seen, and appeared to slowly retire
into holes in the sediment as the camera approached them. One fish of another
species of fish is seen swimming in their vicinity, while a second lay
motionless on the bottom a metre or two away.
All photographs Copyright Dick Raynor 2000
We have seen quite a few eels in Urquhart Bay, and now
we have found the first traffic cone on the bottom of Loch Ness. We will
keep you informed of any future developments of this sinister kind.