A sea monster in Loch Tay?

Does a sea monster reside in Loch Tay?

Loch Tay is a long and narrow freshwater loch with steep sides, over 14 miles in length and 1 mile wide. which follows the line of the valley from the south west to north east. It is the sixth largest loch in Scotland by area and over 150 metres (490 ft) deep at its deepest.

The rivers Lochay and Dochart run into the head of Loch Tay in the west, while the River Tay itself flows out of the loch in the east. Loch Tay acts like a giant reservoir for the River Tay, rumour has it that a strong west wind blowing down the loch can send an extra foot of water down the river.

A number of small ship wrecks have been located in the loch ranging from the remains of a steamship that was blown up in shallow water in the 1950s to an 11 metre long log boat dating to the Middle Bronze Age around 1500 BC.It is popular with fishermen. A Miss Georgina Ballantine ,the ferryman's daughter, caught the largest salmon ever hooked in Britain on the River Tay in 1922, and her record has never been threatened since. So large fish are found in the area.

In 1958:A sea serpent was reported to have been seen on Saturday night in the Tay. The report was made to Fife police by Mr Ronald Avery, bus driver, 3, Milton Crescent, Anstruther and was confirmed by the conductress Miss Betty Kay, Cellardyke. Yesterday Mr Avery said "The bus was standing at the Newport-on-Tay terminus. We were waiting for the starting time and I was standing on the step of the bus looking over the water. It was misty, but about five minutes to eight I was distinctly, about a mile out from Newport Pier, a strange creature moving in the water. Three humps were visible and although it was difficult to tell their colouring I thought they were dark. They were moving towards the Tay Bridge. They disappeared, and then came to the surface again in exactly the same manner a short distance forward. I drew the attention of Betty Kay and together we watched the creature moving towards the Tay Bridge. We must have seen it disappear and surface eighty or nine times, it made a circle towards some boats near the opposite bank. Then it was time for us to move, but I was so impressed that I reported it to the police. I would say it was a sea snake or serpent, about 15 to 20 feet(6 metres)  in length. I don't think the object I saw was porpoises or seals. I've seen sharks and whales in the Indian Ocean but this was the strangest thing I have ever seen in the water.

Then in 2006  Cody Duncan, accidentally photographed the apparent head and neck of something strange in Loch Tay .  He posted  on his blog: "I was doing some editing and saw this weird looking thing. Object enlarged to 300%. Nothing appears in the photo I took 25 seconds before. Perhaps Nessie has a cousin?"
The photograph, shows a black, periscope-like head and neck. 
Source: http://codyduncan.com/blog/2007/12/loch-tay-monster/

There is a history of the Loch Tay kelpie; this supernatural water  horse is said to sometimes appear as a handsome young man.. Each Uisge or kelpie is a shape-shifter who can appear as a fine horse, pony or handsome man. Never try to  ride on its back though. As soon as Each Uisge glimpses or smells the loch its victim will be held fast while it rides to the deepest part of the loch. The rider will be drowned and everything devoured save the liver, which will float to the loch's surface.

So could the Loch Tay monster be supernatural or  does a creature travel up the River Tay into the Loch? It seems strange there has not been more sightings. Dolphins are known to sometimes enter the river and the loch and could appear like a line of humps swimming in formation.Be interesting to see if more sightings are reported.