38 
BULLETIN OF THE BUREAU OF FISHERIES 
Winter feeding, from the standpoint of survival, has resulted in varying degrees of 
success. The highest percentage of survival during the course of the experiments was 
obtained in the 1915 brood when 97.6 per cent of 1,306 animals placed in the brooder 
house in October, 1915, lived until May 15, 1916, at which time the surviving ones 
were removed from the house and placed in outdoor pens (Table 17). The results 
for the preceding brood (1914), however, were the most unsatisfactory, from the stand- 
point of survival, obtained to the present time (1928). Of 1,349 animals placed in 
the brooder house only 53.9 per cent lived until May 24, 1915, when the surviving 
ones were removed from the house. 
The best results under more crowded conditions, such as have prevailed during 
recent years in the nursery house, were obtained with the brood of 1921, of which 
2,395 young were placed in the house in October, 1921. Of this number 87.7 per cent 
lived until May, 1922, when the surviving ones were removed from the house (Table 
17), and this rate, under similar conditions, has not fallen below 68.6 per cent to the 
present time (July, 1928). 
Various methods of sanitation, several different kinds of food, fresh and salt 
water, and wooden and metal (galvanized-iron) tanks have been employed, but 
generally with indifferent success with respect to mortality. After an epidemic of a 
disease (elsewhere described and designated as “sores”) in the brood of 1914, the tanks 
were disinfected weekly with a solution containing potassium permangenate and so- 
dium bicarbonate. In 1922 this method of disinfecting the tanks was abandoned 
largely because it did not prevent the growth of algae. Food and excreta readily be- 
came lodged in the algae, fouling the tanks, and it was necessary to scrape the tanks to 
keep them clean. Thereafter an extra tank was provided, making it possible always 
to have an empty one, and the animals were shifted at about weekly intervals. Each 
trough was allowed to dry, and before replacing the animals it was scalded with hot 
water. This treatment prevented the growth of algae, and a considerable amount of 
work previously necessary to keep the tanks clean was saved. The results with respect 
to mortality, however, were quite indifferent (Table 16). 
It would appear from the rather unsatisfactory records that the death rate during 
the first winter among young terrapins subsisting on foods producing the greatest gain 
in growth (oysters and fresh fish) increased, whereas it decreased when food (salted 
fish) producing little growth was supplied. It does not necessarily follow, however, 
that a larger percentage of the slow-growing animals would reach maturity, for the 
larger and more robust ones appear to stand a much better chance of survival when 
liberated or placed in outside pens. Unfortunately, the data bearing upon this phase 
of the work are very meager. Animals kept in salt water had the appearance of being 
healthier, and generally the death rate appears to have been a little lower. It has 
been thought necessary, however, to supply such animals with fresh water once a day, 
which increases the amount of labor, and the slight advantage gained may not be suffi- 
cient, in practical terrapin culture, to offset the extra amount of work involved. A 
few galvanized-iron tanks have been in use for several years. Such tanks are kept 
clean somewhat more easily than wooden ones, but no advantage from the stand 
point of mortality is apparent. 
Different degrees of crowding of the animals have been tried in the brooder house 
with the view of determining the space requirements of the young animals. In this 
