IOO 



BULLETIN OF THE BUREAU OF FISHERIES. 

 ATTAINMENT OF SALABLE SIZE. 



The relation of age and growth to salability is of importance to the prospective 

 terrapin farmer, and for this purpose a table has been prepared showing the number 

 and per cent of terrapins of the 1910 winter-fed and hibernating lots reaching the 5 

 and 6 inch lengths at given ages (Table 4). The rate of growth of the terrapins in 

 captivity is heavily retarded between the 5 and 6 inch lengths. 



Table 4. — Attainment of Marketable Size by Females of 1910 Brood. 



« Estimated. 



It will be noted that in the fifth year only 1.5 per cent of the winter-fed brood had 

 reached the 6-inch length. In the sixth year 6 per cent of the brood had reached that 

 length. The figures in the table appear small when a mere hundred terrapins are 

 considered. To multiply them several times, however, changes them to the exact 

 meaning they would have for the terrapin farmer — not merely to multiply them by 

 the number of hundreds in the one brood alone, but to multiply them also by the num- 

 ber of broods which contain individuals that are reaching the 6-inch mark. 



In the fifth year it appears that 52.7 per cent of the terrapins of the winter-fed 

 brood has reached the 5-inch mark. Although the price paid for 5-inch terrapins in 

 the market is not nearly so much as that for 6-inch, it is evident that selling when the 

 5-inch mark is reached may have its value from a commercial viewpoint. It means a 

 quicker turning over of the money invested and possibly a better business proposition 

 when large numbers of terrapins are considered. For example, a terrapin farmer may 

 rear from the eggs possibly 15,000 or more terrapins per year. Eliminate one-half (a 

 much too large percentage) for death rate during the five years. Now, in the fifth 

 year, 3,750 terrapins will have reached the 5-inch mark. This is approximately 300 

 dozen, which, sold at $20 per dozen, bring $6,000. The market for 6-inch terrapins 

 would have to be especially good to make the two or three years' extra keeping of them 

 pay. However, the market for 6-inch terrapins generally pays double the amount 

 paid for 5-inch terrapins, and there is the possibility that the raising of terrapins to the 

 6-inch length is the more desirable business proposition, especially when it is remem- 

 bered that there will be an increasing number of broods producing 6-inch terrapins 

 after the enterprise has been carried for a few years, not to mention the increasing 



young production. 



CULLING. 



Each brood of newly born terrapins contains a great many which, when held in a 

 warm nursery house, will not eat, or, if they do, do not make any growth. They serve 

 only to bring down to a lower figure the average annual growth increment of the lot. 



