182 FIELD COLUMBIAN MUSEUM ZOOLOGY, VOL. VII. 



enough to be of commercial value. The difficulty of taking it, or any 

 large fishes, from the lake with nets would be so great as to make fishing 

 for them for commercial purposes unprofitable. 



The water in Lake Atitlan is cool enough and pure enough to 

 justify the introduction of Rainbow Trout (Salmo irideus). This is a 

 very beautiful fish, a very excellent food fish, and one very popular 

 with the professional sportsman who fishes for pleasure with hook 

 and line. It is one of the very best American game fishes. This fish 

 grows to a weight of 10 to 12 pounds in comparatively warm water, 

 the average weight being from 3 to 6 pounds. In very cool water the 

 growth is slow, and the fishes may never exceed one or two pounds in 

 weight. The introduction of the Rainbow Trout is very simple and 

 easy, if care is taken. The eggs can be obtained at hatching stations 

 operated by the United States Bureau of Fisheries, packed in ice and 

 shipped to the lake, and there hatched. After trout eggs have been 

 hatched until the eyes appear as dark spots, their development can 

 be arrested by packing them in moss on trays which are surrounded 

 by ice. Eggs packed in this way have been sent to Europe, Argen- 

 tina, South America, and to New Zealand, and they could easily be 

 taken in this way to Lake Atitlan. The small streams which flow 

 into the lake would furnish a limited spawning area, but the supply of 

 fishes could easily be increased by the addition of a small hatching sta- 

 tion on one of the streams. The artificial propagation of trout 

 presents no serious difficulties. Any intelligent person who is careful 

 can, with a little training, successfully operate one of these stations. 

 The Rainbow Trout is a fish which quite readily adapts itself to sur- 

 rounding conditions. Its natural habitat is in water cooler than that 

 found in Lake Atitlan. It is known to live in water as warm as 75 F. 

 and it is very certain that it will do well in a large body of pure water, 

 such as we find in the lake in question. 



In addition to the introduction of Rainbow Trout, the Steelhead 

 Trout (Salmo gairdneri) and the Landlocked Salmon (Salmo 

 sebago) are recommended. These fishes grow larger than do the 

 Rainbow Trout, and their eggs can be transported and hatched ,in 

 the same way. The Trout and Salmon are much more easily intro- 

 duced into the lake than are any others, and they are far more de- 

 sirable. 



The next desirable fishes to introduce into Lake Atitlan are the 

 Large-mouth Black Bass, the Rock Bass and the Crappie. These 

 fishes would probably do well in the lake, but they should not be 

 introduced if any or all of the species mentioned above are put into the 

 lake. No species of fishes will ever become abundant in this body of 



