338 BULLETIN OF THE UNITED STATES FI9H COMMISSION. 



brooks and ponds where it finds plenty to eat it eats only a small piece 

 of every fish it catches, then lets the fish go, and hunts for another. 

 The presence of an otter can easily be ascertained by its tracks, which 

 are recognizable by the distinct impression of the webbed feet, and by 

 its excrements, generally deposited on flat stones, and containing scales, 

 fish-bones, shells of crustaceans, and remnants of water-beetles. Its 

 presence is also generally indicated by half-eaten fish lying on the 

 shores. 



Small ponds can easily be protected against otters by wire fences 

 about 50 centimeters [20 inches] high and extending t ^e same distance 

 below the ground. As soon as there are indications of otters near large 

 ponds, the whole neighborhood should be carefully searched, and when 

 jwsitive traces of otter have been found, steel-traps should be set, es- 

 pecially near the place where the otters regularly come ashore. 



Among the birds the principal enemies of pond culture are the king- 

 fisher, the heron, the duck, and the diver. Sea-eagles, gulls, and cor- 

 morants are found only near very large ponds or lakes ; and we need 

 not mention them here. 



The kingfisher {Alcedo ispida L.) is a very beautiful bird with brill- 

 iant plumage, 16 or 17 centimeters long [about G.J inches], with a long, 

 straight, and sharply-pointed beak, and short tail. The upper part of 

 the head and neck have a dark greenish-black color, with narrow, close 

 sea-blue bands. The shoulders and wings are dark sea-green, the back 

 has a beautiful blue color, and breast and belly are cinnamon-colored. 

 From the root of the beak a cinnamon-colored, and below it a dark 

 sea-blue streak extends below the eye as far as the shoulder. The 

 throat has a yellowish-red color, the beak is black, and the root of the 

 lower part of the beak and feet are bright red. The kingfisher is not 

 gregarious, but lives alone near brooks, rivers, and ponds, where, chang- 

 ing about between some favorite places, it hides as much as possible, 

 sitting on poles, stones, or overhanging branches close to the surface 

 of the water, and watches for its prey. Frequently it may be seen 

 darting over the water, swift as an arrow, and plunging into it head fore- 

 most, soon to return, carrying in its bill its prey. Its food consists prin- 

 cipally of small fish and crustaceans, and also of large insects. Accord- 

 ing to Brehm, the kingfisher on the average devours every day ten or 

 twelve small fish, each about as long as a man's finger. It therefore 

 becomes very dangerous in trout brooks and ponds, especially as it is 

 by no means so rare a bird as is generally supposed, but is found in con- 

 siderable numbers near brooks containing fish. Max von dem Borne, 

 of Berneuchen, has during fourteen years caught upward of seven hun- 

 dred kingfishers near his ponds. As the kingfisher is in the habit of 

 sitting on stones or stakes projecting a little above the surface of the 

 water, it is easily caught in small steel-traps on whose ju-ong a small 

 piece of wood is placed, inviting it to rest. When caught, it flutters 

 about and falls into the water, with the trap, where it is soon drowned. 



