20 THE REPORT OF THE No. 31 



at some hatcheries attendants are frequently employed to guard the spawn at 

 night in order that it may not be destroyed in this way. 



Bass, pickerel, maskinonge, pike, catfish, sturgeon, rainbow trout, and 

 eteelhead salmon (which are now being taken along the north shore of Lake 

 Superior), are spring spawners; brook and lake trout, whitefish and herring 

 spawn in the fall. 



Bass spawn in from ten days to two weeks in water of a temperature of 

 60 deg., F. ; brook trout in from fifty to a hundred and twenty-five days in 

 water from 37 to 50 deg. ; pickerel (Dore or wall-eyed pike) in from 17 to 20 

 days in water of 45 deg. ; maskinonge in two weeks in water of 55 deg. ; stur- 

 geon in six days, in water of 65 deg. ; rainbow trout iand steelhead salmon, in 

 from 42 to 50 days in water of 50 deg. ; lake trout in from 75 to 90 days in 

 iwater of 40 to 50 deg. ; lake herring in 130 days in water of 35 deg. ; and white- 

 fish in 150 days in water of 34 deg. 



A black bass will deposit from 3,000 to 10,000 eggs a season; a brook 

 trout from 500 to 2,500; a maskinonge from 100,000 to 265,000; a pickerel 

 (Dore or wall-eyed pike), from 45,000 to 125,000; a sturgeon from 500,000 to 

 1,500,000; a rainbow trout, — a three-year-old trout will produce from 500 to 

 800 eggs, and one six years old from 2,500 to 3,000; a steelhead salmon from 

 3,000 to 5,000; a lake trout from 5,000 to 15,000; a lake herring an average 

 of 3,500 (but 12,000 have been taken from a If pound fish) ; a whitefish 

 35,000; and a carp 500,000. 



Herring and whitefish eggs are known as ''semi-buoyant," their specific 

 gravity being slightly heavier than water; trout eggs as "heavy," and both 

 as "non-adhesive." 



There are estimated to be 70,000 herring, 74,000 maskinonge, 6,400 lake 

 trout, 36,000 whitefish, 150,000 pickerel (Dore or wall-eyed pike), and 14,400 

 brook trout eggs to the fluid quart. 



The egg of a brook trout is 1-6 of an inch in diameter, of a lake herring 

 1-10, of a lake trout 1-4, of a maskinonge 1-11, of a rainbow trout or steel- 

 head salmon 1-5, of a sturgeon, 1-9, and of a whitefish 1-8. 



(The above information is gathered from the Manual on Fish Culture 

 issued by the United States Commission at Washington, and other sources. — 

 S. T. B.) 



Returning with the Spoil. 



