FISHERY INDUSTRIES OP THE UNITED STATES, 1925 205 



cated that a sharp decline in the fishery occurred subsequent to 1908 

 and reached one of its lowest marks in 1915. Since then there have 

 been rather large fluctuations in the average yield per boat, but the 

 general tendency has been downward. This has established, beyond 

 reasonable doubt, the fact that there has been a considerable decline 

 in abundance during the past 18 years. 



In answer to the second question, with regard to the independence 

 of the Maryland and Virginia fisheries, similar statistics on average 

 catch per boat indicated that the fisheries in the two States were 

 interdependent, for it was found that when a good season was experi- 

 enced in Maryland there was also a good one in Virginia, and the poor 

 years likewise coincided. This was shown by the life-history studies 

 of Churchill. 2 He found that spawning occurred mainly in Virginia 

 waters, that the young gradually moved up the bay into Maryland 

 waters as they grew, and that when maturity was reached most of the 

 females migrated back to Virginia waters to spawn. In order to 

 corroborate this some tagging experiments were undertaken. The 

 one in which 1,000 tagged crabs were released in Maryland waters 

 in the fall of 1925 yielded data of great interest. Twelve of the 

 crabs so released migrated southward into Virginia waters, where 

 they w T ere recaptured by dredges. All but one were females. Ac- 

 tual count of over 9,000 matured crabs taken in the dredge fishery 

 throughout the season of 1924-25 showed that 77 per cent were 

 females. The reverse was true in Maryland, where 69 per cent of 

 {he trot-line crabs were males. Thus, four lines of investigation all 

 pointed to the same conclusion — that Maryland and Virginia are 

 interdependent so far as the crab fishery is concerned. 



In answer to the third question, as to waste, by taking statistics on 

 the number of " peeler " crabs bought by the shedder houses and the 

 number of soft crabs sold by them it was found that in the season of 

 1924 an average of 53 per cent was lost before moulting. This con- 

 stituted the most important loss in the fishery. Second in impor- 

 tance as a loss to the fishery was the taking of buckram crabs. These 

 are of no economic value whatsoever, but if allowed to remain in the 

 water would become valuable hard crabs. 



In order, therefore, to halt the decline in abundance of crabs, the 

 following recommendations were made: (1) That the taking of 

 sponge crabs be prohibited at all times; (2) that the extent of all 

 forms of crab fishing be reduced 30 per cent; (3) that in order to 

 prevent waste all crabs having a new soft shell fully formed under 

 the outer hard shell be designated " peeler " crabs ; (4) that none 

 but " peeler " crabs be accepted by shedder houses; and (5) that the 

 taking of buckram crabs be prohibited at all times. 



In order to ascertain the effect these changes would have, it was 

 recommended further that provision be made for the collection of 

 statistics and biological data throughout future years; and in order 

 that the findings might be acted upon it was recommended that the 

 State fish commissions be empowered to change regulations, subject 

 to the approval of their respective governments. 



The complete report, setting forth the results of the investigations 

 and including these recommendations, was distributed throughout 



- Life history of the Blue Crab, by E. P. Churchill, ir. Bulletin TJ. S. Bureau of Fish- 

 eries, Vol. XXXVI. 1917-18 (1919), pp. 91-128, 2 text figs., Pis. XLVII-LV, Bureau of 

 Fisheries Document No. 870. Washington. 



