18 THE REPORT UPON No. 36 



of Ontario, since each was in a position to explain its requirements and views. 

 A certain amount of sacrifice is required on the part of all the fishermen involved, 

 if the fishing industry is to be maintained, and the majority, it is believed, 

 recognize this fact. 



Long Point Bay, Lake Erie: 



In addition to the activities of the Branch in connection with the Lake 

 Erie Fisheries' Survey this year, a temporary fisheries' research laboratory 

 was established at Port Dover, a port of considerable importance from the 

 standpoint of commercial fishing. The field laboratory was established primarily 

 for the purpose of making an intensive study of the limnobiology of Long Point 

 Bay. These studies resulted in the capture and identification of fifty different 

 species of fish inhabiting the bay, their abundance, age, sex, measurements, 

 food, and the general limnology of their habitat. Knowing certain conditions 

 at least, the Department is in a better position to regulate both game and com- 

 mercial fishing carried on there. 



Biological Survey of Trent River Watershed: 



One of the field parties spent an entire summer making a biological survey 

 of the chain of lakes included in that part of the Trent Canal System from 

 Lake Simcoe to Lake Ontario as follows: Balsam Lake, Cameron Lake, 

 Sturgeon Lake, Pigeon Lake, Buckhorn Lake, Deer Bay, Upper and Lower 

 Stony Lake, Clear Lake, Trent River, Crow Bay, and Percy Reach. 



From two to five days were spent on each body of water in the chain and 

 during three weeks in September a more intensive study of Stony Lake was 

 made, especially the upper part. 



The general plan of study was similar to that used in limnobiological 

 studies described in the report for 1928. 



Grand River Watershed: 



A very general survey of the Grand River System was made, as a point 

 of departure for more intensive biological studies next year. 



Fishways: 



This year a systematic examination of obstructions along many of our 

 water courses was made, in order to determine whether the present fishways are 

 suitable or desirable and what steps should be taken to correct existing conditions 

 injuriously affecting fish life. Before erecting a fishway, the height of the dam 

 or obstruction must be considered, and also the possibility of a suitable location 

 for the same. The standard fishway used by the Department appears, from the 

 observations of our field men to be suitable. The feasibility of a fishway depends 

 not only on the height of the obstruction, whether natural or artificial, but also 

 on the importance and value of the migratory species in the stream. The 

 available spawning and feeding grounds for migratory species, both above and 

 below an obstruction, must be considered also, in determining the desirability 

 of introducing a fishway. 



Streams containing rainbow trout should not be obstructed, since they 

 have a tendency to migrate downstream from smaller streams to the deeper 



