When first introduced to water, the cubs show considerable reluctance to swim. This can hardly be because they are unable to do so, but rather owing to a youthful aversion—as in the case of a puppy—to entering a strange element for the first time. The bitch therefore takes them to a stone in midstream, and either pushes them in, or leaves them there until they are at last tempted to enter the water and follow her. On the sea coast otters spend a good deal of time searching for flounders in the shallow pools. They also eat crabs, lobsters, sea anemones, and various crustaceans. Otters sometimes visit the lobster fishers' creels, and there are instances on record of partially grown otters having been found drowned in the creels. On inland lakes and streams otters feed on fresh-water mussels and cray-fish.
As previously mentioned, it is no uncommon thing to find the remains of fur and feather in otter coke. Otters capture waterhens and dabchicks, although we are of the opinion that they prefer other food if they can get it. At any rate we are familiar with a certain reed-fringed pond on the hills, where a bitch otter and two cubs of about 12 lb. weight resided for some months. This pond was also occupied by quite a number of waterhens, yet there were no apparent remains of these birds to be found in the vicinity, which pointed to the fact that the otters left them pretty much alone.
A rather curious thing happened when we visited the pond with hounds. At first the waterhens were much in evidence, but after hounds had been at work for an hour or two, we began to find dead waterhens lying about. These were not killed by hounds, but were drowned, and had practically—as far as we could see—committed suicide. To escape danger a waterhen will keep diving, and the birds under discussion had evidently—owing to the continual presence of hounds—done so until they were tired out, and subsequently perished under water. What made their behaviour stranger still was the fact that there was a small covert adjoining the pond, in which the birds could have found sanctuary on terra firma until all danger was past.
Both dabchicks and waterhens devour fish spawn, so otters do good by thinning out the ranks of these birds. At times otters will take game-birds, and there are authentic records of grouse, pheasants, and duck having been killed by them. One or two instances of this will suffice. In "The Natural History of Sport in Scotland," by Tom Speedy, the latter says: "That he can scent and pounce upon his prey like a fox was demonstrated by following his tracks among snow up Corrie Macshee Burn at Dalnaspidal. The trail left the water-side and showed where the animal had made a bound and caught a grouse in its roosting-place among the snow. Returning to the stream, he had crossed on to a boulder in the centre of the burn, where he devoured part of his prey." The same author mentions a case of an otter on the Biel estate in East Lothian, which dragged a foster-mother hen out of a coop and partly devoured it, as well as a number of young pheasants big enough to sit out amongst the grass. Traps were set, baited with the dead bodies of the birds, and a large otter was secured; the massacre then ceased.
In The Gamekeeper for August, 1913, there is a note concerning the deaths of fifteen sitting pheasants in a covert beside a river. Each bird had a hole gnawed down through the back, the carcasses being left lying near the nests, not an egg having been touched. A duck caught on her nest is treated in the same way by an otter. In The Gamekeeper for June, 1919, there is a note concerning an otter which was caught in a tunnel-trap baited with rabbit paunch. The trap was set in the middle of a one hundred acre wood. The otter was a cub, weighing 9½ lb.
Waterhens and dabchicks, particularly the latter, when taken by otters, are pulled under the water, though they may be captured amongst the reeds and other undergrowth as well. Ducklings sometimes fall victims to the otter, though as a rule big pike do the greatest harm in this direction. Pike have been known to take pheasants as well as duck which had fallen into a lake during the course of a shoot. From available evidence, otters on a stream containing trout and coarse fish seem to prefer the latter. Possibly they are easier to capture than trout. On hill-streams, where the fish are small but very numerous owing to shortage of food, otters must do a great deal of good by reducing the stock.
As far as furred prey is concerned, otters will kill and eat rats, water-voles, and young rabbits. We have on several occasions seen where a small bunny had been caught by an otter. On marshes where duck shooting is carried on, otters find and feed on wounded duck, exactly as do foxes. Here again they do good by acting as scavengers, as well as by putting winged birds out of their misery. Rabbits appear to be the largest four-footed creatures preyed upon by otters, but we have heard it suggested by an old Lakeland dalesman that they will on occasion take lambs. Although we bring forward this suggestion with great diffidence, it is quite possible that there is some truth in it. Our informant lived by the shore of a lake in an out-of-the-way part of the country, where at one time pine-martens were very plentiful. It is a well-known fact that martens will kill lambs, and an otter, which is a much more powerful animal, could easily do the same if so inclined. Anyway, the old dalesman more than once found the carcass of a lamb left close to the edge of the water on the lake shore, with the tracks of otters round about it. Neither a hill-fox nor marten would be likely to drag or carry the carcass to water, and the whole thing certainly pointed to the work of otters.
An otter is a predaceous animal of the weasel family, strong, and active in its habits, and would experience no difficulty in tackling a lamb. It is never safe to be dogmatic in one's statements concerning the habits of wild creatures, because generally speaking, the only regular thing about them is their variability. Cases have occurred where otters were responsible for killing ducks, grouse, pheasants, and rabbits, and though such behaviour is only occasional on the part of the average otter, it shows what he will do when so inclined.
In winter otters are sometimes hard put to it to find food, and they have been known to take poultry at such times. In the same way regarding the dalesman's statement about lambs, an otter may occasionally kill one, although most people would laugh at such an idea. We know that hill-foxes take lambs, having scores of times found carcasses in and about the earths, yet one meets hunting people who resolutely refuse to believe that Reynard ever falls so far from grace as to feed on lamb. A fox will eat trout when he can get it, and so will many dogs. We have one now which eats small trout as greedily as a cat, and no doubt foxes secure many fish when the hill-streams are dead low in summer. It is no more strange for a fox or a dog to eat fish than for an otter to take an occasional lamb. All three are carnivorous—the otter being least so—and when all is said and done, wild animals show very unusual traits at times.
Summing up the otter's feeding habits, we find he kills fish, and in the case of salmon he is certainly wasteful. To set against this he takes many a sickly fish, as well as cannibal trout, all of which are better out of the way. He kills waterhens and dabchicks, both devourers of fish spawn, and he slays quantities of eels, which are the worst vermin to be found in lake or stream. Game is only an occasional item on his menu, and nobody grudges him a few young rabbits.