214 Conservation Department 



few were taken considering the emphasis placed on the catching 

 of little carp. This may be due to the destruction of large numbers 

 of eggs by natural causes, to little carp living in deeper water 

 than the young of game fishes or to some protective habit as tak- 

 ing shelter in the mud bottom and thus escaping our nets. 



Both in the canal and in Oneida lake yearling carp were taken 

 in the seine together with adults. The weight of these young 

 carp from the lake averaged one-half pound ; the total length nine 

 inches. Those caught in the canal w^ere somewhat smaller. 



Migration. — With an object of determining to what extent carp 

 migrate, we placed an aluminium tag on the caudal fin of two 

 hundred adult carp. Each tag bears the initials N.Y.C.D. together 

 with a number which identifies each fish with a record of its length, 

 weight, sex, the date and exact place of liberation. The distri- 

 bution of tagged fish was as follows : — 



Oneida lake 70 



Erie canal at New London 50 



Seneca division of canal 50 



Oswego canal 30 



It is anticipated that through more extensive seining operations 

 and the cooperation of local fishermen, who catch tagged fish, 

 many of the tags will be returned together with the place of 

 capture, so that our records may be completed. The degree of carp 

 migration, its direction and rate outside of a purely natural history 

 interest has an important bearing on the subject of carp control. 



Food Habits. — The digestive tracts of forty-two adult carp 

 taken at ten different places in the barge and Oswego canals were 

 examined by Mr. Sidney Britten.* His condensed report 

 follows : — • 



Plant material 31.4 per cent. Per cent 



Vegetable debris 25 . 



Filamentous algae 5.0 



Seed 1.4 



Animal matter 68.6 per cent. 



Insect larvae 24.8 



Snails 16.4 



Midge larvae 5.0 



Bivalves 6.5 



Ostracods 4.8 



Malacostraca 3.0 



Animal debris 2.8 



Oopepods 1.9 



(Madoeera 1.6 



Decapoda 1.1 



Insects .5 



Crustacea ( unideiil ilied ) .2 



* Scientific assistant in field unit. 



