0.4 - 



0.3 - 



CO 

 O 



z 



D 

 O 

 Q. 



I- 0.2 



I 



o 



HOMEWOOD LAKE 



HEAVY STOCKING 

 POOR FISHING 



UJ 



0. I 



1933 



FORK LAKE 



NO STOCKING 

 GOOD FISHING 



FALL 



SUMMER 



BLUEGILLS 



I SPRING 



1934 



1935 



1936 



1937 



1938 



FIG. 8. — Increase in weight of bluegllls In Homewood Lake under conditions causing 

 stunting, and increase in Fork Lake under optimum conditions. The growth of the 1938 

 brood bluegllls, spawned in Fork Lake, is shown through 1938 and 1939, 



LIMNOLOQICAL OBSERVATIONS 



Llmnologlcal observations on Fork Lake for 1939 Included a continuous record of water 

 temperatures at a depth of about 3 feet with a Frlez recording thermograph, plate 1; trans- 

 parency readings made with a standard Secchl disc; and water levels read at weekly inter- 

 vals or oftener. These records have been compared with average weekly maximum and minimum 

 air temperatures and rainfall, recorded at the Decatur weather station, about 6 miles from 

 Mount Zion. Frequently, vertical temperature sections were taken with a reversing ther- 

 mometer. Records were begun the first week in March, after all the ice of the lake had' 

 melted. 



Rainfall, transparency and water level readings are listed in table 9. In table 10, 

 maximum and minimum weekly air temperatures are listed, together with average water tem- 

 peratures. In fig. 9, these phj^ical data are summarized in a single illustration. At 

 the top of this figure are shown the average weekly maximum and minimum air temperatures 

 and their relation to average water temperatures. The difference between these maximum 

 and minimum air temperatures for any week is 20 to 30 degrees F., with the water temper- 



12 



