U. Bottom samples confirmed the indications of the underwater photographs 

 that surface appearance of the three areas was similar. Mixing of the 

 sandy-mud layer and the underlying clay was more pronounced in both 

 fished areas than in the control. Fished areas were also softer and 

 had less odor of decomposition than the control. No difference in the 

 above physical characteristics was observed between dredged and bull- 

 raked sections , 



$. Breakage of commercial -sized clams was recorded during the experi- 

 mental fishing. Bullraking operations broke about 0.1^ of the clams 

 above U5 mra- but most of this breakage was from handling. Dredging 

 broke about 1.0^ of the clams above 60 mm. in length. Even though 

 dredging breakage vras 10 times that of raking, it is still extremely 

 low in this sandy-mud bottom, and is not considered to be important. 

 The observations of Narragansett Marine Laboratory agree with our 

 records for this type of bottom, but list dredge breakage of 2.9% in 

 rocky bottoms. In one instance, 21.1^ breakage was observed in a 

 rocky-shelly bottom. 



6. Breakage of undersized clams by raking and dredging was found to be 

 negligible in the sandy-mud of the test plot, but this might not be 

 true in rocky or shelly ground. 



7. Observations of recently dead clams made during bottom sampling showed 

 no evidence of significant mortality in either fished area. 



8. No setting occurred on the test plot during the summers of 19U9 and 

 19^0. Therefore, no observations could be made on the effect of fish- 

 ing upon setting and set survival. 



9. Bottom samples and underwater photographs indicated fewer living 

 bottom forms in the test areas than in the control. Decrease in 

 number of tube worms, Gistenides , was especially noted. No difference 

 was shown in the effect of dredging and raking on bottom forms asso- 

 ciated with the clams. 



10. The disappearance of 35.7^ of clams in the control area from 19U9 to 

 1950 has been demonstrated by statistical analyses. A similar dis- 

 appearance of the larger group of clams occurred in the bullraked 

 section between September 30 and December 15, 19U9. Natural mortality 

 could not have caused this loss or shells would have been found in 

 bottom samples. It is therefore concluded that these clams were 

 removed by illegal fishing. 



11. This experiment shows no biological basis for restricting either 

 method of fishing. 



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