PROGRESS IX BIOLOGICAL IXQUIRIES, H>21, 19 



aquatic vegetation the blue-spotted sunfish will prove a valuable 

 addition, and if very shallow or swampy areas occur, the mud min- 

 now. The common killifish is very effective in fresh and brackish 

 tidal marshes, and the translucent killifish is useful in upland creeks 

 and dams. Eapid multiplication of small fishes should be encouraged 

 by providing suitable nesting sites and protection for the fry. 



(lambusia, the favored top minnow of southern waters, has not 

 survived the northern winters but multiplies so rapidly that it may 

 be used effectively again.st both C'ulex and Anopheles in small ijonds 

 and Avater gardens bj^ planting a small number each spring. Small 

 goldfishes are useful in fountain basins and small ponds with clean 

 sides, and, for use in rain barrels and tanks, are preferable to Gam- 

 busia. 



FISH-CULTURAL EXPERIMENT WORK. 

 EXPEIUMEXTS IX I'Kdl'ACJATI X(; AND KKAKING FISH IN TONUS. 



The Fairport station has contiuued its \ ahiable experimental work 

 in reference to the propagation and rearing of fishes in ponds. Cer- 

 tain observations Avere made on the value of fertilizing ponds with 

 chemicals and manure. l)ut data oljtained to date are inconclusive. 

 Further study will be directed toward this probkMU. 



The small poiub Avliich for several years has been luindled as a farm 

 pond witii miuimum care and expense, has yiehle<l \aluable informa- 

 tion. Originally it was stocked with bluegill sunfish. Occasionally, 

 when necessary, the jjond has been wintered out. There has been no 

 manipulation of the pond in any resjx'ct other than the control of tiie 

 number of bluegills of varions ages in it. During the past year the 

 actual production of fish meat in the j^onds has been .S.'^H pounds jier 

 acre. Of this, however, fisiics of edible size represented about o-"') per 

 cent of the total fish-meat production. In this connection it may be 

 well to note that the avei'age annual jjroduction of beef per acre on 

 untilled meadowland is said to be 125 pounds; that for hogs is 225 

 pounds. 



Buffalofish, Ictiohiis ci/prinello^ artificially reared in the station 

 ponds, reached maturity and produced young for the first time at the 

 age of 4 3'ears. They averaged l.'i.G inches in length and approxi- 

 mately 2 pounds in weight. 'J'he small-mouth bull'alofish, I(f'i()hH>i 

 }>uhahiH^ which in previous years had failed to spawn in the experi- 

 mental ponds unless an artificial rise in the level of the pond was 

 produced, spawned this year in a pond in which the rise did not 

 occur. AVhile the production of fry of this species does not api)ear 

 to be as numerous ius for tho.se fish held in the pond with artificial 

 rise, the occurrence indicates that the rise is not entirely necessary, 

 though it may be advantageous. 



Tiie channel catfish, htahinift pvnctatux^ for which this station 

 showed the feasibility of pond culture, has continued to spawn in the 

 ex])erimental ponds. Certain 4-yeai'-old offspring of wild stock came 

 to sexual maturity during the yeai' and ])roduced the first brood of 

 truly domestic fish. Tlie adaj^tabiiity of this species to pond culture 

 is suggested by the fact that the catfish has spawned in certain of the 

 smallest jjonds on the reservation, one of which has a water-surface 

 arpa, when completely full, of only 3,485 square feet (less than one- 

 twelfth of an acre). 



