FISHERY BULLETIN: VOL. 69, NO. 2 



Table 2. — Surviving transplants, successful transplants, and monthly mortality of transplanted sprigs of Thalassia 

 in a finger-fill canal, phase II, April through October 1967. 



Method of anchoring 

 and treoting 



Trons- 

 plants 



Surviving plants 



Mortality! 



Unsuccessful* 



Successful^ 



May 



July 



Aug. 



Sept. 



Pipe* 



With apexes, with NAPH 

 With opexes, without NAPH 

 Without opexes, with NAPH 

 Without apexes, without NAPH 



Total 



Bricks 



With opexes, with NAPH 

 With apexes, without NAPH 

 Without opexes, with NAPH 

 Without opexes, without NAPH 



Total 



Construction rod^ 

 With NAPH 

 Without NAPH 



Total 

 Grand total 



60 



n 









 33.3 

 16.7 



25 



* Mortality not observed in June. 



' Transplants survived but did not exhibit new rhizome growth. 



* Tronsplants exhibited new rhizome growth. 



* Rhizomes were buried; two sprigs per anchor. 



^ Rhizomes were not buried; three sprigs per anchor. 



« Rhizomes were removed before planting; tv/o sprigs per anchor. 



Pipe and brick were poor anchors. The sprigs 

 anchored with pipe were transplanted with their 

 rhizomes and special care was required in bury- 

 ing them to avoid breakage. Almost half of the 

 24 sprigs held with pipe lived to the end of the 

 experiment, but only 3 exhibited new rhizome 

 growth (Table 2) . Sprigs secured to the bottom 

 with brick were not buried but were simply laid 

 on the bottom and the substrate was scooped 

 over them by hand. They were also transplanted 

 with their rhizomes but were difficult to handle 

 because of their tendency to slip out from under- 

 neath the brick before they were finally set in 

 place. Six of the 24 sprigs lived for awhile, 

 but only 2 were successful. Sprigs that were 

 anchored with brick and failed did so shortly 

 after they were planted. Water movement prob- 

 ably eroded away enough sediment to allow 

 the buoyant sprigs to float from under the brick. 



TREATMENT OF TRANSPLANTS IN PHASE II 



The effect of NAPH on marine grasses is ap- 

 parently similar to its effect on terrestrial plants, 

 primarily inducing rapid and heavy rooting. 



Ten of the 11 sprigs producing new rhizomic 

 growth were treated with it (Table 2) . Because 

 of the small number of transplants attempted 

 and successes achieved, we cannot definitely 

 establish the significance of NAPH in such ex- 

 periments. Our results indicate to us, however, 

 that NAPH was one of the main factors con- 

 tributing to transplant success. 



Particular care was taken to avoid damaging 

 rhizomes and rhizome apexes of sprigs before 

 and during transplanting. No apparent advant- 

 age was gained from this care ; invariably old 

 rhizomes withered away and were replaced by 

 new ones developing from the bases of the short- 

 shoots. 



MORTALITY OF TRANSPLANTS 



Visual checks made throughout the year 

 showed that the most critical period for the 

 survival of turtle grass was during the first 

 3 months after transplanting. In phase I, mor- 

 tality of plugs planted in the canal was 60% 

 through the third month (October), 22.5% 

 through the sixth month (January), zero 



278 



