The triple-trellis technique does not require identification of fish 

 recaptured more than once whereas the Jolly does so a model was devised 

 which simulated multiple recaptures and Jolly estimates were calculated 

 both with and without correction for multiple recaptures. The total 

 population for the 5-week sampling period was obtained by adding the 

 calculated number of recruits per week to the initial estimate. Weeks 

 with survival probability (Jolly's phi) greater than 1 were assumed to 

 have large recruitment so that the number joining was adjusted upward by 

 the proportion above 1. Negative recruitment numbers were treated as 

 zeroes. The population estimates (to nearest 1,000) for 1975 ranged 

 from 147,000 as determined by the triple-trellis technique to 160,000 + 

 39,000 (2 standard errors) for the Jolly technique with correction for 

 multiple recaptures to 168,000 + 37,000 for the Jolly technique without 

 the correction. The corrected Jolly estimate (Table 2) was used in 

 subsequent reports as the best estimate for the 1975 Niantic River 

 population of winter flounder. 



In 1976, the winter flounder population survey was designed for use 

 with the Jolly method (NUSCo 1977). Fish were still marked by fin 

 clipping but recaptures were also tagged with a spaghetti tag to eliminate 

 the problem of not recognizing multiple recaptures. Sampling began 

 during the first week of March and continued through the last week of 

 April and approximately 1,000 winter flounder were marked per week. A 

 total of 9,856 winter flounder were marked and 699 were recaptured. The 

 total population was calculated as 83,000 + 13,000 (Table 3). 



The population survey in 1977 took place during the weeks of March 

 7 through May 9. Freeze branding replaced fin clipping as the method of 

 marking and both week and station codes were branded on individual fish 



