26 BULLETIN OF THE UNITED STATES FISH COMMISSION. 



March. Only 6.1 per cent of the total catch were egg lobsters, and while this number 

 would have been increased if the traps had been scattered instead of kept in definite 

 spots, it would contrast markedly with the results at No Man's Land, where more than 

 half of the total catch were lobsters with external eggs (table 1). 



In severe winters lobsters are driven into deeper water or forced to protect them- 

 selves by burrowing in the mud. The effect of sudden or extreme cold upon these 

 animals may be witnessed in lobster pounds, where they are kept iu large numbers 

 to supply the winter market. On the Vinal Haven Islands, near Rockland, Maine, 

 there is a large pound belonging to Messrs. Johnson and Young, of Boston, of 12 to 

 15 acres in area. It is said to have an average depth of 18 feet at low water. In 

 January, 1S93, during a cold snap, ice was formed over this pool to the thickness of 31 

 inches. At this time many of the lobsters died. All the pollock also, which had been 

 placed in the pond, were killed, some of them being 2 J feet long, and large numbers 

 of hake at the same time succumbed. 1 



Lieut. W. M. Wood (207), while transporting live lobsters from New York City to 

 Chesapeake Bay, tried some experiments upon the effect of reducing the temperature 

 of the water. Lobsters placed in water at the freezing-point were just alive after 

 one hour's immersion. He was of the opinion that lobsters could be kept alive for a 

 number of days in a cold chest, with a temperature of from 40° to 50° F. The practice 

 of transporting lobsters by the aid of ice is now generally adopted. 



The annual range of temperature throughout the stretch of coast inhabited by 

 the lobster is less than might be supposed. The temperature of the surface water of 

 Winter Quarter Shoal, Virginia, ranges from 35° to 76° F.; at Five Fathom Bank, 

 New Jersey, the range is 37° to 76°. Delaware Breakwater, which is practically the 

 southern limit of the lobster, is situated between the light-ships anchored upon these 

 two shoals. At Sandy Hook light-ship, north of the Five Fathom Bank, New Jersey, 

 we have an annual range of 33° to 74°; at Bartlett Reef and Hartford Shoal light- 

 ships, on Long Island Sound, it is 33° to 70°. The middle portion of Vineyard 

 Sound, farther east, has a similar range, while at the Brenton Reef and Vineyard 

 Sound light-ships, the region of Block Island, the Elizabeth Islands, and Marthas 

 Vineyard, tlie temperature varies from about 32° to 09°. The range at Woods Hole 

 (see table 2) is about 29° to 73°, taking the means for each month, while the actual 

 extremes are greater. At Pollock Rip light-ship, at the southern end of Cape Cod, 

 the mean range is 32° to 62°; in the Gulf of Maine the same range is obtained by 

 combining the results of observations at all stations. In some places the maximum is 

 only 54°. The preceding data are extracted from a paper by Mr. Rathbun (157). 



Mr. J. H. Duvar says that from 1878 to 1880 the average temperature on the north 

 shore of Prince Edward Island was 56.56° in June, 63.40° in July, and 62.27° in 

 August. The temperature of the water at bottom in 6 to 8 fathoms he estimated 

 roughly at 55°. Lobsters spawn in July on the north shore; in August on the south 



'The inspector of fisheries of Prince Edward Island has an interesting note on the capture of 

 lobsters through the ice in his annual report for 1882 {210). He says that on March 10 of that year 

 there were brought to him "a number of lobsters of a uniform length of body [probably meaning 

 carapace or shell of the back] of 4 inches, and one weighing 3 pounds that had been taken throuo-h 

 the ice by the scoop of a mud-digging machine in a creek off Cascumpeque Bay. They seemed rather 

 sluggish, but not torpid." It is evident that these lobsters preferred to burrow in the mud rather 

 than migrate into deeper water. 



