92 U. S. BUREAU OF FISHERIES 
to 14,140 for the present season, and is the highest record obtamed thus 
far in the culture of this species. The greatest previous annual pro- 
duction was obtained in 1938, when 13,600 were hatched in the 7 
concrete breeding pens surrounding the station. gi his is the worl s 
largest terrapin farm, or hatchery, and has supplied approximately 
144,000 of these salt-marsh turtles for restocking coastal areas since the 
artificial propagation of this species was undertaken in 1909. The 
1939 brood has been placed in special hibernating boxes in the large 
rearing house and will be distributed next spring throughout the South 
Atlantic region in cooperation with the various State conservation 
agencies. 
The increased yield from these operations in the past 2 years can 
be attributed to experimental improvements made under the direction 
of Dr. Prytherch and Capt. Charles Hatsel, with respect to reducing 
the concentration of brood stock in certain of the breeding pens. For 
example, in one pen where the adult terrapin were provided with 
twice as much space in 1938 and 1939 as in 1937, the production of 
young increased from an average of 8 per female in 1937 to 10 and 
1114 per female, respectively, in 1938 and 1939. Also, in the two 
new large pens, which provide ample room for the brood stock, the 
total production of young for each group of 500 adults—consisting 
of 400 females and 100 males—increased from 1,200 in 1937 to 3.360 
in 1938, and 3,490 in 1939. In all of the experimental pens, in which 
crowding has been reduced, the average production of eggs per female 
terrapin showed increases ranging from 20 to nearly 200 percent in 
the past 2 years, with a fertility of over 95 percent. The increased 
production of young diamond-backs in 1989 is particularly significant 
and encouraging because seasonal conditions in that year were appar- 
ently less favorable for breeding than usual, as the 2 “control,” or 
unimproved pens showed a decrease of over 20 percent in output in 
comparison with the average result obtained over a previous 5-year 
period. Also, during 1939, the brood terrapin were frequently dis- 
turbed, and their ege-laying activities were interfered with to a 
considerable extent while a P. W. A. project was in progress. This 
project made extensive improvements by elevating the concrete walls 
of all the pens, providing new tidal gates, and by enlarging the area 
of the egg beds. 
The total brood stock at present consists of 570 males and 2,025 
females, most of which have been in captivity for a period ranging 
from 10 to 25 years. In 1937 one of the pens was stocked with 320 
wild terrapin, at a ratio of 70 males to 250 males, in order to determine 
the length of time required to reach satisfactory eg@ production. 
The output of young terrapin from this group increased from 460 in 
1938 to 790 in 1939. Considerable interest in the terrapin-culture 
method developed at the Beaufort Station has been shown by the 
fisheries commissioners of Maryland and Virginia, who plan to 
inaugurate similar operations in their States within the next 2 years. 
In the spring, the output of the Beaufort Station usually is distrib- 
uted in the coastal region from Maryland to Florida, after the young 
terrapin have been protected and fed for the first 9 months of their 
lives. This work has not only provided a large supply of young 
terrapin for restocking depleted salt-marsh areas, but has saved thou- 
sands from destruction by natural enemies such as rats, gulls, crabs, 
e 
