Secondly the water is pitch black once you get a few feet down. The water runs off the mountains and down the hillsides surrounding the Loch bringing with it particles of peat which are suspended in
Then there is of course money. To do a sophisticated proper investigation would cost a great deal of money. Most researchers are self financing or get small grants from their workplace. Since the 70s no one seems to have come forward to want to invest in looking for Nessie. Most researchers go up to investigate in their holidays from work, very few are able to afford to spend large amounts of time at the
Which brings us to Nessie. Nessie is seen as a joke due to all the hoaxes perpetuated over the years and very few scientists want to be involved . It can cost you your job and certainly held back some people’s careers. The fact it is seen as a hoax means many people have closed ranks and no longer report sightings and locals laugh when you ask. They don’t want to be seen as foolish. The number of times I have heard “Well I will tell you if you promise not to write it down or anything. I don’t want reporters round”. (I don’t like to tell them that being dyslexic I memorise the conversations but I don’t write them down. It is something I learned to do at meetings at work because I couldn’t write down notes fast enough. By the time I had decided how to spell something they had moved on to something else lol. These days of course I would record them or take a laptop). Though that has been a huge amount of sightings over the years , when you divide them by the number of years , it is not a lot. Nessie is quite shy.( taking the average figure of 3000 sightings since 1930s ,divided by the number of years ( 80) it is an average of about 40 a year ). If you then weed out the unlikely and definite mistaken identity you are left with about 2 unexplained sightings a year. It is not a lot is it? Then the chances of getting a decent photo are even remoter. Most people on seeing something can’t believe their eyes and by the time they have recovered enough to grab a camera ,it is often too late, the whatever it is, has gone. So the odds are against us all. That is a sample of reasons why I think nothing conclusive has never been found to support the existence or non existence of the Loch Ness creature.
The only answer is large amounts of cash and sophisticated equipment and trained people to operate it and interpret results in an all year round expedition to search the loch thoroughly. So if anyone has won the lottery and has a spare million????