46 DEPARTMENT OF THE NAVAL SERVICE 



6 GEORGE V, A. 1916 



at a later date in the summer. Supervision and caretaking over a large area must be 

 limited in some way, or the expense of running the pond would te very great. Con- 

 sequently the department came to the conclusion that the northeast part of 

 the pond should be inclosed by cement walls, making what may be called a cement 

 pound within the natural pond. [See subdivision II of the general plan of the pond.] 

 To ensure that animals confined in it should have an adequate suppV of fresh 

 sea-water, the pound was connected with St. Mary's bay by an earthenware pipe 20 

 inches in diameter, ^hen the tide outside rose higher than the bottom of the pound, 

 a valve opened automatically, and it was expected that a large volume of sea-waler 

 would be retained in the pound. The scheme looked feasible, but the cement pound 

 as it existed in the summer of 1914 was quite useless, because it would not retain 

 water as planned.^ 



OTHER USES FOR THE POUND. 



Three other uses have been suggested for the cement pound besides that of affording 

 protection for berried lobsters. One of these was that the Biological Board should 

 use it for the purpose of rearing lobster larvae to the lobstering stage, that is, to the 

 stage at which young lobsters cease to live at the surface of the water and descend 

 to the bottom. 



In accordance with this suggestion the writer spent three days at the pond about 

 the middle of May, and reported to the board that while no use could be made of the 

 cement pound for the purpose suggested, on account of the insufficiency of the water, 

 even at high tide, he thought a small experimental rearing plant of the Wickford 

 type could be located at the opposite or southwest end. 



Even there the writer was in doubt as to whether there was a sufficient depth of 

 water at low tide. He found the depth to be not more than 5^ feet. The rearing 

 boxes which it was proposed to use would be 4 feet deep and would be immersed about 

 3^ feet in the water so that there would be less than 2 feet below the boxes, where 6 

 feet at least would be regarded as a minimum. Thus, before the experiment was 

 undertaken at all, the insufficiency of the depth of water and area of water in the 

 pond was pointed out. Moreover, this limited area of 25 feet by 75 feet would admit 

 of the installation of only four hatching boxes, whereas the full complement of boxes 

 in the Wickford system contemplates as many as twenty-four boxes. In order, there- 

 fore, to have an area of sufficiently deep water anywhere in the pond, to justify the 

 installation of a complete rearing plant, it would be necessary to dredge an average 

 of about 7 feet from the bottom of the pond over an area of approximately 400 feet by 

 60 feet. Either this, or a deep canal would have to be cut in the sea-wall, and enough 

 water admitted from St. Marys -bay to flood the pond 6 feet deep at low water. Which 

 of the two plans would be the more economical is a question which only an expert 

 hydraulic engineer could decide, but neither plan should be adopted until our present 

 plant has been run for another season at least. 



THE WICKFORD PLAN OF REARING YOUNG LOBSTERS. 



The Wickford plan of rearing lobsters was the result of eight or ten years' of 

 experimentation by Professor A. D. Mead and his assistants working under the auspices 

 of the Ehode Island Fish Commission. Up to 1898 nearly all efforts to increase the 

 lobster supply artificially were limited to hatching lobster eggs in jars. 



Now, lobster hatching must be clearly distinguished from lobster rearing. Just as 

 the hatching of chickens is a different process from the rearing of chickens, so the 

 hatching of lobsters is quite a different matter from the rearing of lobsters. The 



1 Since this report was written, the Deputy Minister of Naval Affairs informs me that the 

 leakage of water from the pound has been stopped, and that the mud and slime on the bottom 

 have been removed under the direction of a Government engineer. 



