Biological Survey — Oswego Watershed 79 



into deep water. The yearling carp were found in schools similar 

 to the adult carp but not associating with the more mature fish. 



Young carp are found scattered over a favorable habitat, each 

 individual conducting itself independently of other young carp. 

 In seining it was never possible to catch more than two or three 

 of them in any one haul. On July 21 at Damon's point twenty 

 little carp were taken from one of the shallow set-backs, covering 

 an area of not over thirty square feet. A similar catch was made 

 at Clough's bay July 27, in a growth of short grass. In each of 

 these instances the cover was excellent and this fact probably ac- 

 counts for the large number in a small area, On September 7 at 

 Damon's point a strip of shore three hundred feet long and extend- 

 ing fifty feet into the lake Avas systematically seined. The territory 

 had several beds of Potamogeton pectinatus, Elodea and Chara, 

 each an excellent cover for young carp. Only ten fish were caught 

 in this area. Such data show how widely the young carp of 70 mm. 

 to 100 mm. are distributed over a favorable habitat. 



Invariably a little carp will hide rather than seek safety in flight 

 if molested. It is this characteristic which makes them so difficult 

 to find. When catching them with a hand-net it is possible to 

 work over a whole bed of Chara or Elodea without driving the fish 

 away. Not until they reach a length of about 100 mm. do they 

 seem to appreciate the possibility of fleeing from an intruder. On 

 September 15, several carp over 100 mm. in length were seen to 

 dart out from small patches of Potamogeton (P. pectinatus). 

 Their movements were very rapid and directed toward deep water. 

 Even the youngest carp observed were fast swimmers, comparing 

 favorably with young darters which are frequently found living in 

 the same habitat. Several pens of young carp were kept in Clough 's 

 bay for purposes of study. Here we found they spent a consider- 

 able amount of time completely buried in the mud and sand. This 

 habit is undoubtedly valuable for very young fish living in shallow 

 water, as a means of protection, especially against predacious birds 

 and sudden changes in the temperature. 



Small carp are very sensitive to temperature changes and also 

 to impurities in the water. To test these reactions, young carp 

 were placed in aquaria with young sunfish, bullheads and common 

 perch. A sudden change of temperature invariably affected the 

 carp first, Any pronounced change in the hydrogen-ion concentra- 

 tion, due to the presence of decaying matter, was fatal to the carp 

 although not to the other young fishes living with them. In their 

 natural habitat young carp were seldom found in the vicinity of 

 green algae such as Spirogyra or Cladophora, decaying vegetable 

 matter, or quagmires. 



The feeding habits of young carp are very interesting. On July 

 21 some carp fry 12-26 mm. long were observed feeding, about 

 noon, in a bed of Chara at Damon's point, Twenty individuals 

 were scattered over an area of some thirty square feet. The fish 

 would start in at the base of the stalk, work up the stem and then 

 down the other side, then go to another plant and repeat the 

 operation. At times they would work out onto the leaves, but 



