vocsel ovjncrs ims that nets in these fisiiurios were lost priiaarlly duo 

 to roGiilar vcar and tear and secondarily as a result of entanglement 

 uitli oDa tractions. The vear and tear is mainly due to the chafing of 

 tiio £;car on the shell and gravel seabeds. The other factor is the 

 reduction of tensile strength caused by microbiological deterioration 

 of tne ttjine. An average of three to four nets are vorn out annually 

 by vessels fishing in these regions. 



From two to five nets are used annually by vessels fishing 

 in Mississippi and Louisiana. Boat ouners there claim that nets saidom 

 •wear out when their vessels fish in the delta area. Nets are lost niainly 

 as a result of bogging. A secondary factor is the sharks which tear 

 groat portions of the cod end section. 



Tests by Robas (195^4 ) have shovm that in southern -waters 

 menhaden nets treated with copper napthonate and seine tar retained ac 

 inucn as 82 percent of their tensile strength after tliroe months' exposure. 

 After a similar period of exposure untreated twine or pine tar-treated 

 nets retained no tensile strength. It is believed that considerable 

 savxngs in net costs in the shrimp fishery, especially on the Atlantic 

 coast, can be made by treating nets in copper based solutions. 



Nylon trawls which have a reputation for being more durable 

 tttin cotton have been tried in various areas. In South Carolina one 

 experienced fisherman reported that the not spread well if the size of 

 tiiG doors was reduced. A dii'ficulty apparently arose whenever the nylon 

 not had to bo mended which prompted this particular fisherman to abandon 



its U33, 



In Texas, a net maker reported that cod ends made of mylon 

 lastod throe times as long as those made of cotton. The cost is about 

 35 percent tiigher than regular twine. Thirty- thread nylon or combina- 

 tion nylon netting was recommended. 



One shrimp vessel captain from Broxmsville reported excellent 

 results with nylon netting. He stated that despite the higher initial 

 cost, n-st expenses for a year's operation xrore roducod from :ii>3,000 in 

 19I>3 to '>;ll;.500 in 19Sh by the saitch-ovcr from cotton to r^ylon xiebbing. 

 Tnis vessel operator also used nylon in place of manila rope in the 

 rigging. Ho reported that if a net became hung during traxjling, he 

 ueuaily liianaged to save the nylon net whereas the cotton not often 

 ripped and poi'tions of it wero lost. Perhaps this vjas due to the greater 

 strength of tne nylon xjebbing. He reported no problems as a result of 

 webbing bslng cut on rough surfaces, 



Louisiana vessel owners felt that, since in their particular 

 area the nets and cod ends were being destroyed usually early in thy 

 uoa-lii'e of the gear*, there vjas no real economy in equipping boats with 

 tne more expensive nylon nets which were vulnerable to bogging. 



An increase in tlie use-life of the gear in the Mississippi 

 dolta area depends on reducing the losses caused by bogging down in the 



86 



