PROGRESS IN BIOIvOGICAL INQUIRIES, 1934 397 



In conjunction with the Corps of Engineers, United States Army, 

 survey work, analyses, and experimental tests were made back of 

 several of the new dams which have been constructed as part of the 

 Mississippi River channel project and recommendations made con- 

 cerning the effect of these constructions on water conditions, fish food, 

 and other fisheries interests in the impounded waters held by these 

 dams. 



MUSSEL PBOPAGATION 



The mussel propagation experiments which were started at Fort 

 TVorth 2 years ago have been continued throughout the past year, and 

 detailed data collected concerning the growth, mortality, and resist- 

 ance of fresh- water mussels which are being grown under controlled 

 conditions in close quarters in the experimental rac-eways at the 

 Forth Worth project. The results of these experiments continue to 

 to be favorable to this method of artificial propagation, especially for 

 certain species. As a corollary of the work at Fort Worth, a new 

 shipping container has been devised, making it possible to ship live 

 mussels long distances with very little l<:>ss. 



rNDEPENDZNT ACTIVITrES OF THZ FISHZEIZS BIOLOGICAX 



LA30IIAT0EIZS 



WOODS HOLE, iLiSS. 



Lack of sufficient funds for the operation of the Woods Hole lab- 

 oratory prevented the Bureau of Fisheries from providing the custo- 

 mary facilities for independent investigations at this laboratory. 



Robert A. Xesbit. assisted by William C. Xeville. ran parallel series 

 of tests of methods of marking scup by insertion of tags into the 

 coelomic cavity, in which it was found that the most successftil 

 method consisted of inserting flat celluloid strips l^s by tV inches. 

 With this method S percent of the tags were lost during the first 3 

 weeks, and none was lost during the following 12 weeks of observa- 

 tion. By developing a marking technique in which losses are small 

 and definitely ascertained, it becomes possible not only to trace the 

 migrations of this species but also to determine what portion of the 

 mortality is due to commercial fishing and what portion is due to 

 natural causes, two items that are fimdamental in formulating a con- 

 servative policy. 



EEAUFOKT LABOBATOKT 



The Beaufort (X. C.) laboratory was severely damaged to the ex- 

 tent of over 810,000 by the tropical hurricane of September 16. 1933. 

 It was possible, however, with fimds provided by the Public Works 

 Administration, to restore the buildings and equipment by the fol- 

 lowing spring and continue operations for the propagation of the 

 diamondback terrapin, and investigations concerning oil pollution and 

 serious natural enemies of oysters in the South Atlantic and Gulf 

 region. With additional fimds provided by the Public Works Ad- 

 ministration, a bridge has been constructed to connect the lalx>ratory 

 with the mainland, which will increase the protection of the Bureau's 

 property in case of fire and tropical storms and will enable the gen- 



