I'h'EFACE vii 



SESSIONAL PAPER No. 38a 



is not feeding, according to zoologists. In the opinion of the commission, sea-lions 

 should be reduced in number, or driven away from localities where damage can be 

 done: but on many rookeries there is no necessity for extermination, especially as valu- 

 able products (oil, leather, and fertilizer) might be obtained by creating a sea-lion 

 industry. In such case, a wise method would be to adopt official control of sea-lion 

 destruction conjointly with conservation, and a certain number only to be killed each 

 year. 



The second part of the report describes, in detail, the various rookeries, and esti- 

 mates the total number of sea-lions upon them. 



II. LOBSTER IXVESTKiATIOXS. LOXCI BEACH POXD, X.S.— 

 (Prof. A. P. Kxight). 



The author, in his report on the lobster investigations at the Government pond 

 in Xova Scotia, during the season of 1915, commences by distinguishing between the 

 nature of the sea lagoon, or pond of 5 acres, and the pond of three-quarters of an 

 acre enclosed by cement walls. In 1914 the latter leaked extensively, but the depart- 

 ment repaired the leak. Later, leakage again occurred, but was repaired, and on Dr. 

 Knight's arrival on June 26, 1915, the water was 5 feet 8 inches deep, at low water. 

 Next month it leaked again, and the rearing boxes (10x10x2^) rested on the mud, 

 and by August 7, two boxes were immersed 5 inches in the mud. At the United States 

 lobster station, at Wickford, K.I., where rearing was first carried out, there is always 

 12 feet of water underneath the boxes at low tide, excepting at one corner, where 

 there is 5^ feet. 



Early in July a vegetable parasite threatened the young larvae, there being 40,000 

 hatched in the four boxes by July 14, but the parasite was Licmophora Lynghyei 

 (in 1915), instead of the species in 1914, Synedra investiens. To avert loss of fry, two 

 boxes were removed into the water of the bay, but 20,000 fry were retained in two boxes 

 were removed into the water of the bay, but 20,000 fry were retained in two boxes 

 in the pond. Nearly all the latter were lost, only twenty-one surviving, in the second 

 stage, on July 30. On August 2 a further trial with over 20,000 fry had a similar 

 disappointing result; only 146 fry, in the second stage, survived until August IT. 

 When canvas shades were used, to shut off the sunlight, the first stage lasted nine 

 days instead of thirteen (when unshaded), and the water was 1 degree warmer. The 

 greater success at Wickford. where 40 per cent of the lobster fry were reared, may 

 be due to: (1) greater depth of water under the boxes; (2) comparative absence of 

 mud and diatoms; (3) a higher temperature, 68° to 75° instead of 58-09° to 58-9°, 

 and these conditions are of paramount importance. If the sea-water were heated to 

 68° or 70°, it would require 250 pounds of coal every twenty-four hours to efi'ect this, 

 as 2 cubic feet of water i^er minute passes through each rearing box. 



The adult lobsters, early in 1915, were found to be covered with growths of 

 sea-weed, and from that cause, and the miaddy water, out of 167 left in the pond, 

 33 appeared to have perished; but of 312 not more than 38 died from the pound-condi- 

 tions in 1915, the reduced mortality being due to care in collecting, feeding, and 

 distributing them, and in shorter detention. 



The author's notes on the egg-laying of lobsters are very interesting. Half of 

 the females extruded only a few hundred eggs, instead of many thousands, and at 

 least 80 per cent of these eggs were unfertilized. Unfertilized eggs soon drop off, 

 and it is easy to see why fishermen find so many she-lobsters not carrying eggs, and 



