ted. Total effort expended by each type of gear 

 was determined by multiplying the length of 

 each net, in yards, by the number of days fished 

 by that type of net. The sum of the individual 

 efforts gave total effort in yard-days. This 

 same procedure was used to obtain total effort 

 for all commercial gear. Catch per -unit-effort 

 was obtained by dividing the catch by the total 

 effort (table 1). Effort by bow net and by hook- 

 and-line fishermen was not determined. 



Bow nets are large and cumbersome and 

 as they are left at the fishing site when not in 

 use, they can easily be counted from a boat in 

 the river. At the height of bow net fishing a 

 boat tour of the river revealed that 207 bow nets 

 were in use. Bow nets do not require a license 

 on the Edisto and apparently large numbers of 

 them are fished. Logbooks kept by 47 operators 

 of bow nets, revealed that the average seasonal 

 catch of each net was 19.3 shad (range 2 to 63) . 

 Assuming that this sample was representative 

 of the average catch, it is estimated that the 

 bow nets caught a total of 4,000 fish . 



Sport fishing 



Several camps on the river rent boats, 

 but many of the boats used for sport fishing are 

 privately owned and are brought to the river 

 and launched. A post -card survey was used to 

 estimate the total number of shad taken by sport 

 fishing. The 60-mile sport-fishing area was 

 divided into two 30 -mile sectors; sector 1 ex- 

 tended from West Bank to Harts Bluff, and 

 sector 2 extended from Harts Bluff to Canadys. 

 Each sector was cruised by boat every other 

 day from March 5 through May 1 — , and a post 

 card was given to each fishing party. Each day 

 that a sector was surveyed, it was cruised 

 twice (upstream in mid-morning and down- 

 stream in the afternoon) to contact all fisher- 

 men . Each fishing party was requested to 

 report the number of male and female shad 

 caught, the number of fishermen in the party, 

 and the length of time fished. The card number, 

 sector fished, and date were entered by the 

 census taker. Throughout the census period, 

 317 cards were given out in sector 1, and 70 

 were given out in sector 2. Fifty-six percent 

 of the cards were returned ir^m sector 1, and 

 51 percent were returned from sector 2. 



Calhoun (1950) made a study of post- 

 card response in California, where post-card 

 surveys have been used extensively to estimate 

 the sport-fishing catch. He found that the cards 

 were returned at random, and he could detect 

 no bias in the data. In other words, fishing 

 success or failure did not influence the return 

 of the card. Assuming that the post cards dis- 

 tributed in this survey were returned at random, 

 as was found to be true in California, an esti- 

 mate of the Edisto River shad catch made by 

 hook-and-line can be made. 



According to data obtained from the 

 survey, a total of 376 boats fished in sector 1 

 and 83 boats fished in sector 2. These figures 

 are higher than the total number of cards dis- 

 tributed, because at times all fishing parties 

 could not be contacted. As expected, not all of 

 the cards that were distributed were returned; 

 however, according to data obtained from the 

 returned cards, 179 boats caught 322 shad in 

 sector 1, for an average catch per boat of 1 .80 

 shad, and 36 boats caught 38 shad in sector 2, 

 for an average catch per boat of 1 .06 shad. 



As stated above, the river was surveyed 

 only on alternate days, therefore to obtain the 

 total number of boats that fished during the 

 season, the actual count of boats was doubled - - 

 making a total of 752 boats for sector 1 and a 

 total of 166 boats for sector 2. Multiplying 

 these figures by the average catch per boat for 

 each sector and adding the products (752 x 1 .80 

 + 166 x 1.06) gives a total catch of 1,530 shad. 

 For purposes of this study, the figure has been 

 rounded off to 1,500 shad (table 2) . 



Population estimate 



A tagging and recovery program was 

 conducted to determine fishing rate, size of 

 run, and spawning escapement. Shad were 

 caught and tagged throughout the fishing season 

 at West Bank by means of a set gill net. The 

 catch was inspected regularly to ensure that 

 only vigorous specimens were tagged. A 



3/ Sport fishing began approximately March 5 

 and ended before May 1 . 



