176 Field Columbian Museum ^- Zoology, Vol. VII. 



mended introduction into waters other than those in which they are 

 now found is made with a little hesitancy. I am very sure that the 

 introduction of those that I have named will do no harm, and the 

 chances are that to introduce any or all of them will considerably 

 increase the supply of food fish in the lake. 



If quantity of fishes or of fish food, at the expense of quality, is 

 desired, the German Carp is recommended.* The Carp is a large, 

 coarse fish which grows very rapidly. It is also very prolific. A 

 female of 25 pounds' weight, brought to the Museum a few weeks ago, 

 contained about 1,750,000 eggs. This fish is much cultivated in small 

 ponds in Germany, Austria and other European countries, and for 

 small ponds they are much desired, for they grow more rapidly than 

 do most of our better food fishes. At one year old, they weigh about 

 one pound. At three or four years of age, they grow in ponds to a 

 weight of 6 to 8 pounds. In large bodies of water they grow even 

 more rapidly. In the Fox River, near Chicago, Carp are often taken 

 of over 30 pounds weight. In the Illinois River more pounds of 

 Carp are taken by commercial fishermen than of all other fishes com- 

 bined. The Carp feeds upon plants, and of this class of food there is 

 an abundance in Lake Amatitlan. 



If Carp are introduced into the lake, it would not be so desirable 

 to put into it the Large-mouth Black Bass, or the other fishes men- 

 tioned. In eating vegetation the Carp digs up the bottom, much as 

 do hogs. In this way they might destroy spawning places for Mojarras, 

 Large-mouth Black Bass, and other fishes, and the areas suitable for, 

 spawning places for these fish are small. In addition to this, they are 

 sure to become abundant enough to stir mud and sand around the 

 shores to the extent of making the water very muddy. In this way, 

 the Carp would partially destroy some of the beauty of the lake. 



In the introduction of the fishes mentioned the important thing 

 to decide is whether first-class fishes are desired or not. If they are, 

 the Carp should not be introduced into the lake. It is not nearly so 

 good a food fish as is the Mojarra. If Carp are introduced, the supply 

 of fishes for food will be many times as great as it is now, and perhaps 

 twice as much as if the other species mentioned were introduced. The 

 introduction of Carp is quite sure to decrease the abundance of better 

 fishes, such as the Large-mouth Black Bass, the Crappie, the Rock 

 Bass and the Guapote. For the introduction of any of the fishes 

 mentioned, the food supply is abundant. The water is clear and pure, 

 and the temperature is such that they would feed during the entire 

 year, and thus grow rapidly. 



* Mr. J. W. Tioomb itrongly b«li«vet German Carp ihould not be introduced into this lake. 



