Some persons seem to think that it is impossible for the Water Ouzel to walk at the bottom of the water, owing to its body being of less specific gravity.  I will not argue the point with them, but disbelieving my own eyes, I will endeavour to submit with a good grace; otherwise I should have said that I have repeatedly seen it doing so, from a situation where I had an excellent opportunity of observing it, the window of a building directly over the place where it was feeding.  It walked into the water and began to turn over the pebbles with its bill, rooting almost like a pig, and it seemed to have no difficulty whatever in keeping at the bottom at all depths where I could see it; and I have frequently observed it when the water just covered it, and its head appeared above the water every time it lifted it up, which it did incessantly, turning over a pebble or two, then lifting its head, and again dipping it below to seize the creepers (aquatic larvae) it had disturbed from their hiding-places.  Besides, its speed was too slow for diving.  Every aquatic bird with which I am acquainted moves much faster when diving than when it is swimming or walking, and its course is generally in a straight line, or nearly so; but the Water Ouzel, when feeding, turns to the right or left, or back again to where it started, stops and goes on again, just as it does when out of the water.  Yet when it wished, it seemed to have the power of altering its own gravity, as after wading about two, or perhaps five minutes, where it could just get its head out, it would suddenly rise to the surface and begin to swim, which it does quite as well as the Water-hen.  The awkward, tumbling, shuffling wriggle which it appears to have, is occasioned by the incessant motion of its head as it turns over the gravel in search of creepers, which appear to me to form the bulk of its food.

Sir George Mackenzie seems to think that these birds destroy salmon spawn, and this opinion is prevalent in Scotland.  If it is correct, it would go far towards putting an end to my partiality for them; but I rather think that they are unjustly accused, and believe they are catching creepers when they are supposed to be eating spawn.  If this is the fact (and it is well worth ascertaining) they are rendering an essential service to the fisheries instead of injuring them, because these creepers (the larvae of the stone-fly, bank-fly, and all the drakes) are exceedingly destructive to spawning-beds, and as the Water Ouzel feeds on them at all other times, and as they are more abundant in the winter than at any other season, I think this is the more probable supposition.  Of course, if Sir George Mackenzie has shot the bird, and speaks from his own knowledge, after dissecting it, there can be no doubt of the fact that it destroys spawn; but if he merely supposes so because the Water Ouzel feeds in the same streams where the salmon are spawning, it is very probable he is mistaken, for the reasons before mentioned. (May 29th, 1834).