6 GEORGE V SESSIONAL PAPER No. 33a A. 1916 



IV. 



LOBSTER SAI^CTIJARIES AND HATCHING PONDS: AN INVESTIGA- 

 TION OF THE LONG BEACH LOBSTER POND, DIGBY 

 COUNTY, NOVA SCOTIA, IN 1914. 



By Professor A. P. Knight, M.A., M.D., F.R.S.C, etc., 

 Professor of Animal Biology, Queens University , Kingston. 



(With six plates). 



ACKNOWLEDGMENTS. 



Acknowledgment is due to the Department of Naval Service, Fisheries Branch, 

 for placing all the berried lobsters in the pond at the disposal of the scientific staff. 

 Without these it would have been impossible to carry on the investigation. 



Acknowledgment is due also to Professor Prince, the chairman of the board, for 

 furnishing important references to the literature of the subject. In fact, it was he 

 and Professor Macallum, the secretary of the board, who suggested the invt stigation. 



SCIENTIFIC STAFF AT THE POND. 



A. P. Knight, M.A., M.D., Professor of Physiology, Queen's University. 



H. G. Perry, M.A., Professor of Biologj-, Acadia I'niversity. 



W. E. Sullivan, Ph.D., Professor of Anatomy, University of Milwaukee. 



A. B. Dawson, Acadia University. 



W. Arnold Mersereau, University of New Brunswick. 



RESULTS OF THE INVESTIGATION. 



The following summary of the results of the investigation and of the conclusions 

 reached will indicate the lines of the research. 



In considering whether a rearing plant should be permanently located at Long 

 Beach, certain very obvious disadvantages must be squarely faced: — 



(1) The place is not easily accessible, consequently transportation and freight 

 charges are excessive. 



(2) The water is too cold and, therefore, delays the development and moulting of 

 the larvae. 



(3) There is not nearly depth enough of water even under the pre-ent number 

 of hatching boxes, there being only 18 to 20 inches under our four boxes at low tide, 

 whereas there should be at least 6 feet. If the full complement of boxes (24) are to 

 be installed, an area of 400 feet by fiO feet by 10 feet depth would have to be provided. 



(4) Too great a growth of moulds, diatoms, and Cyanophycese, causing pollution 

 of the water and sickness and death among the larvae. 



(5) Too much cloudy and foggy weather, thus depriving first stage larvte of the 

 sunshine into which they naturally swim whenever they can. 



As against these disadvantages may be placed two very important adviintages, 

 namely, placidity of surface and suitable salinity. The surface of the pond is pro- 

 tected from high winds throughout its length by a hill on the west side and the high 

 sea wall on the east. According to Mr. Martin, whq investigated the subj' ct last 

 season, the salinity nearly equals that of the bay of Func^'y. The amount O"*" fresh 



