Omida Lake J-islus 5oy 



trans|K)rtcil M.mf <listaiKc- l)y water currents, and cloubtlcss adheres tu the first 

 object with which it comes in contact: and "in the spawning area most closely 

 observed, this object woiilil necessarily be a grain of current-washed gravel ; in 

 other areas, it would be some plant in the submerged vegetation." The many 

 notes carefully gathered by Hubbs on the life history of this sjiecies suggests to 

 him the following conclusion: "That I.ahiilislhiS siccuJus is a fish characterized by 

 an annual life-cycle, breeding but once at the age of one year, then dying and leav- 

 ing the young-of-the-year as the only link over the winter connecting the genera- 

 tion of one year with that of the next." Cahn {'2j. p. 03) concludes that indi- 

 viduals live from fifteen to seventeen months. He also (p. 64) gives many notes 

 on the breeding of this sjwcies in Wisconsin Lakes. The season was May and 

 June, the time correlated with the temperature of the water. The spawning iK'gan 

 at ()i^° V and reached a climax at J2.i)'' F. in Oconomowoc Lake (p. 66). The 

 fish first were seen in pairs, the male swimming alxtve the female (p. 64 ). During 

 the height of the spawning season several males may be with a female, "but this 

 poly-association usually terminates by one of the males driving away the others." 

 Cahn vividly describes spawning as follows : ".\ school of silversides reveals a wild 

 sight when spawning activities are in full sway. In and out dart the females. \)ut- 

 sued by one or more males, darting this way and that, shooting an inch or more 

 out fif the water and landing again three or four inches from the s|)«>t of their 

 emergence amid a sjiatter of spray, followed immediately by the attending male 

 retinue. Suddenly the female slows down her i»ace and comes to what amounts 

 to a lompanitivc rest. The first male to reach her approaches from the rear and 

 draws up along side. This ajiparently is a signal for the departure of any other 

 males that may l)e pursuing that particular female, for never have I seen any dis- 

 turknnce once a male is associated along side of a female. Other males simply 

 disperse and join the chase of other females." 



Ifiihitat. There is undoubte<lly a seasonal change of habitat for we fouiui the 

 s|H'cies abundant in shallow water in Se|)tember. 191 5. and scarce there during June 

 and July, I<>|6, when we found but one sjiccimen ( Xo. 385^, July jo. at Lower 

 South Hay. Mvermann Cm, p. ^^48) notes a seasonal movement in small lakes of 

 northern Indiana, but this appears difTerent from the one in Oneida I -ike. He 

 says: "It em-s in large scIicmiIs which, during the summer, may In? seen swimming 

 at the surf.ice out in the lake far from shore: while during the spring and late in 

 the fall it comes in near shore, where immense schools may Ixr seen, aiul where it 

 remains even tuUil after tlie ice In-gins to form " 



We foimd the schools of this s|H*cies in Oneida I.ake chiefly over xand and 

 stony liottom, and in all cases where vegetation was scarce. Osburn ("01. p. "f> > 

 considers it to favor sandy or gravelly liotioms in the shallow waters of lakes and 

 it i« found near the surface of deep water ( Hcnslcy. '15, p. 38). RadclifTe ("15. 

 p. 13") says that it lives luuirr a variety of conditions, but occurs in greatest 

 abundance in small sluggisli rivers, nuiddy lowland lakes, ponds, sw.imps, and 

 sloughs. I'.vermann and Clark ( '-•o, \'ol. 1, pp. ,^85, T^jCt) note a shoreward migm- 

 tinn of the sin-cies in the fall and (p. .^76) say that in sununer it is pretty well 

 distributed throjighout the surface waters of the lake, "where they can freqttcntly 

 Ih> seen jumping nut of the water in low hori/ontnl curves, a whole school some- 



