Untitla Lake fislus 379 



"All this demonstrates that to lie most effective a portion of the boards should 

 lie in the shallow water for the use of early sjjawners. It also strongly sug},'ests 

 that the flow of water into the iK)nd sIkjuUI Ik- so re|,'ulated as to prcxluce the highest 

 temperatures attainable in the early part of the season. In the morninj,' the supply 

 should be reduced or cut off entirely, while at iii!,'ht. when the water may be warmer 

 than the air, it should be turned on in full supply. 



"In this connection I would reconmiend that where i)racticable water for the 

 su])ply of catfish jHjnds would iK-st be taken from some other pond, so that a 

 higher temin-raturc may be maintained, especially early in the sea.son and during 

 periods of low atmospheric tem|)erature. We have alxnit 32 or 33 catfish in each 

 of our ponds K and M. the former being of about twice the area of the latter. K 

 is supplied direct from the s])rings, M from a 2-inch iron pipe from jwnd L. one 

 of our largest and warmest ponds. The catfish hatch has been more than double 

 in .M what it has been in K and. for all we know, one i>ond is as favorable fc^r the 

 lish as the other, both having muddy bottoms and an abundance of vegetable 

 growth. We believe that the temperature of the two ])onds is responsible for the 

 difference. .\s .soon as the weather grew hot all of the beds were |)laced under 

 boards in j or 3 feet of water and not one in the shallows. 



"This matter of tem])erature may account for the unfavorable results some 

 seasnns when practically no catfish are hatched in even the wild ])onds, and other 

 conditions than temperature may also have a controlling influence. It is proliable 

 that mudily water would be unfavorable and even low atmospheric pressure al.so, 

 lishes Ix-ing more susceptible to changes of pressure than air-breathing animals. 

 "From the start we have watched developments in our catfish ponds K and M. 

 Ihe first ]>oint of special mite is that the fish were seen spawning alwiut a month 

 earlier than usual, although it must Ir- admitted that a nnich closer watch was kept 

 (daily, almost hourly) than ever before. It has Iteen suggeste<l that jMissibly the 

 ciMitentment brought by the homes afforded by the boards may have hail some 

 influence in favoring re])nMiuction. .\t all events our hatch has U-en more success- 

 i\i\ than for the past six or seven years, and we know of no other cause to ascrilie 

 n to. 



"Our first surprise wa- at the >horl jieriod of incubation of the eggs. Itased 

 oil temperature and the period of other fishes, the time should have been alniut .'4 

 to 7,n hours, but these catfish egg-i hatched in less than 20 hours. How much k-.> 

 we do not know, but every effort to find ovit positively will Ik- made during the 

 remainiler of this season and next. In the two cases observe<l so far this season 

 we were thwarted in getting the ex.ict time by the fisli coming off unex|>cctc<IIy 

 early in the morning or in the night. The tem|KTature of the water at the IkvIs in 

 both cases under observ.ilion was 77' i" to 78' j" I"., varying with the time of day. 

 "The first case closely watched was on May S. when at <) 30 a. m, a feniale 

 catfish was seen in a clepression. such as previously descril)ed. in almut i^ inches of 

 water and 3 feet from shore, in fine ]iosition for close ol»scr\atit»n. ."she was over 

 a quantity of light orange -colored eggs, forming a gelatinous mass alx>ut 4 inches 

 wide and 5 long and api>arentlv three- fu\irtl>s of an inch thick or deep. They kvl 

 everv ap|x'arancc of k-ing freshly de|x>sitcd. the water still being somewhat muddy 

 owing to tlic cligging of the depression. The male was lying some thrcr feet away 



