LOBSTER SANCTUARIES AND HATCHING PONDS 47 



SESSIONAL PAPER No. 38a 



former process has been carried on in our Dominion hatcheries since 1891. Hitherto 

 our liatcheries have confined their efforts to scraping the eggs from the abdomen of 

 the mother lobster, placing them in jars of well aerated sea water and, when the young 

 have come out of their " shells," emptying them into the sea. Many millions of young 

 lobsters have been hatched in this manner every year since 1891. 



The rearing of lobster babies for three or four weeks before putting them into 

 the sea is the main feature of the Wickford system. In this system the mother lobsters 

 do the hatching just as naturally as they hatch the young in the sea. The only 

 difference is that in the Wickford plant the mother or berried lobsters are placed in 

 large hatching boxes 10 feet long by 10 feet wide and 4 feet deep, set down in the sea 

 about 3i feet. The water in these boxes is kept aerated by revolving paddles. The 

 animals are shaded by canvas covers, and regularly fed. You may call these boxes 

 the "nests" of the mother lobsters if you like. At any rate they serve the same 

 purpose as nests do in the rearing of young birds. 



Every evening, especially if the weather is fine and the eggs ready to hatch, the 

 mother lobstef may be seen moving' to and fro those parts of her body to which the 

 eggs are attached, and presently a considerable number of the young escape from 

 their "shells" and swim about near the surface. 



These young are removed from the hatching box to other boxes called rearing 

 boxes of the same size but with different- length of paddles revolving in them. The 

 "babies" are dipped up with shallow dip-nets made of cheese cloth, and are usually 

 counted with the aid of an automatic counter. As many as 25,000 may be put into a 

 rearing box; but at Long Beach we never transferred more than 15,000, and gener- 

 ally only 5,000 to 8,000, as we were anxious to rear quality rather than numbers during 

 our first season. 



With the transfer of the young, or larvae as they will often be called, to the rearing 

 boxes, the real work of rearing young lobsters begins. Feeding the larv£e is perhaps 

 the easiest part of all. At Wickford they are fed chiefly upon hens' eggs, scrambled 

 and pulverized ; but clams and fish finely shredded are equally good. 



Three big difiiculties confront the operator : (1) the aeration of the water in the 

 rearing boxes; (2) the prevention of cannibalism among the larvae; and (3) the spread 

 of infectious disease. 



The aeration of water in the boxes in -which lobsters, young or old, are kept is 

 just as necessary as fresh air is for hiiman beings or for domesticated animals. In 

 fact, the aeration of water for aquatic animals corresponds precisely to ventilation 

 for terrestrial ones; for, just as fresh air must be admitted to our houses, and frowsy 

 air allowed to escape, so the stale sea-water in the hatching and rearing boxes must 

 be replaced by fresh sea water if the lobsters are not to be smothered for lack of 

 oxygen. The mechanism by which aeration is brought about will be described later on. 

 As to cannibalism, it is generally recognized that the younger and weaker larvae 

 are subject to danger from the stronger and more active ones. The more the larvae 

 are crowded together, as they must necessarily be in rearing boxes, the greater the 

 extent to which the habit is likely to grow. Lack of food must tend to promote sucli 

 a habit, as one can readily understand. If, however, the larvae are kept moving about 

 rapidly in the water of the rearing boxes, they are to some extent kept separate from 

 each other and thus the danger of cannibalism would be greatly reduced. Aeration 

 of water and reduction in cannibalism would be both controlh^d, to a very consider- 

 able extent at least, by the rate at which the water circulates in the boxes. 



Perhaps the greatest difiiculty of all is the prevention of disease. Just as human 

 beings are killed by infectious diseases like measles, scarlet fever, diphtheria, .^lual'- 

 pox, and consumption, so our first batch of 40,000, as well as our second batch of 

 30,000, were nearly all attacked and killed by infectious diseases caused by very tiny 

 plants. Three of these plants are known as diatoms, and the fourth as a fungus. 



