Common Bullfrog — Part 7

Rana catesbiana Shaw

Each of us has actually before him, or in memory, a typical pond or small lake, for our country is everywhere made picturesque by them. We have waded there for lilies, or fished from its sheltered coves for pickerel, or perhaps for frogs. It is called, indiscriminately, "the lily-pond," or "the frog-pond." The lilies make a large part of its beauty, the Bullfrog a large part of its life. The Bullfrog is the spirit of the place. (Fig. 290.) Independent, self-composed, silent, he may sit for hours with no slightest movement to tell that he is alive. But he is fully alert to every disturbance of the water and to every shifting shadow. Not only is he alert in sight and hearing, he is ready in muscle for a sudden movement at any second. If a dragon-fly skims over the water's surface in front of him, the insect is swallowed quickly. If a sparrow comes for its daily bath beside what seems to be a moss-covered stone, its brown tail feathers are seen a moment later protruding from the frog's mouth, while the frog is sitting sedately in just the same spot. Sometimes a bird drops from the overhanging bough above, because of the correct aim of some gunner and becomes a trophy for the frog instead of for the man.

However, it is not appetite alone that brings into play the alert senses and muscles of the Bullfrog. Let a bear approach from the wooded shore ever so stealthily, when his paw comes down suddenly over the frog, he finds he has nothing but water-weeds and mud to pay him for his trouble. (William J. Long.) A heron hunting frogs has no chance of catching the Bullfrog, if the frog is on the bank. It is only when the Bullfrog is in the mud that he is speared by the powerful beak. Ages of generations of contest with this enemy have not taught the frog to bury the hinder portion of his body when he plunges into the mud. He may not see the snake, his greatest enemy, and so, at last, he is lost. But what eyes could see its sinuous body moving so cautiously, neither shape nor motion differentiated from the surrounding water and the waving plant stems?

And so, in pond and marsh, the contest goes on, as it always has in past ages. Each day the life of the individual is given to maintain the life of the species, and the balance of life among the races is kept, although the scales may tip somewhat now in one direction and now in another. Very definite and very emphatic is our admiration for the individual. Each represents high specialization along a given line of development, and seems perfected to the minutest detail in its fitness for its life. Each is so invisible in its environment that it seems wonderful that an enemy ever finds it at all. Each is supplied with the power of extremely rapid movement. However, certain characteristics may be of the greatest advantage to a given individual, but of the greatest danger to that individual when the same powers are possessed also by an enemy. Thus the rapid flight of a bird or insect is counteracted to its disadvantage by the invisibility and rapid movement of the frog, and these characteristics of the frog are offset fatally for him by the same characteristics and the power of stealthy approach in the snake.

So life goes on, and gladsome but arduous days are passed by the denizens of the pond.

1882. Notes on the Habits of the Savannah Cricket Frog (Acris crepitans). Amer. Nat., vol. xvi, pp. 707-711.