An image of the toad taken by MIT

The Massachusetts Institute of Technology (MIT) has been attempting to unravel the mysteries of the loch.

However, MIT said it did not expect to come across the amphibian so far down.

Bob Rines, a lecturer at MIT, will tell the Oceans 07 engineering conference in Aberdeen about the toad and the survey next month.

Conference chairman Professor John Watson, of the University of Aberdeen, said: "They were surprised to find a toad at that depth."

MIT said it had completed a side-scan sonar map of the entire length of the loch - which is about 750ft (228m) at its deepest point.

'Picturesque patterns'

The data has been compared with a geological map of the bottom made by Sir Edward Murray using plumb lines 100 years ago.

The institute said the scan was part of its continuing efforts to find animal remains preserved at the low temperatures at the loch bottom that might explain unusual sightings on the surface.

Professor Watson's presentation to the conference will cover details of how the loch has changed over the past century.

This includes "picturesque patterns" in the silt caused by water pumps for a hydroelectric plant.

Oceans 07 takes place from 18 June to 21 June at the Aberdeen Exhibition and Conference Centre.