released to the Maryland Department of Re- 

 search and Education. The scarcity of shad in 

 the early thirties and the difficulty of obtaining 

 enough fish in spawning condition to fill hatch- 

 eries caused many States to abandon or greatly 

 deemphasize their programs by 1940. In I960 

 only Virginia was hatching shad, and these 

 operations were limited to a small scale in 

 the Pamunkey, Mattaponi, and Chickahominy 

 Rivers. 



Hatcheries, as operated, did not maintain 

 shad runs- -as shown by the steady decline in 

 populations. To evaluate the effect of shad 

 propagation on subsequent runs, Talbot (1954) 

 studied factual information on hatchery op- 

 erations and estin-iated the size of the total 

 populations entering the Hudson River in 

 1915-50; he found no correlation between the 

 two variables. Talbot also reported that the 

 number of eggs obtainable for hatchery op- 

 erations is only a nninute fraction of the amount 

 spawned naturally; the increased survival rate, 

 if one exists from current shad hatchery 

 practices, has not produced and cannot be 

 expected to produce an increase in the shad 

 population. Studies on the Connecticut River 

 revealed findings similar to those on the 

 Hudson. 



Progress might be made in hatchery tech- 

 niques that would justify their re- establish- 

 ment for propagation of shad. As practiced 

 in past years, however, propagation cannot 

 now be justified as a means of sustaining or 

 increasing the catch. 



FISHWAYS 



It was recognized early that where dams ob- 

 struct upstream passage of anadromous fish, 

 fishways should be provided to enable adults 

 to reach upstream spawning areas. Fishways 

 constructed during the late 1800's and the 

 early 1900's failed to pass fish (fig. 30). One 

 exception was a fishway constructed in the 

 Lackawaxen Dam on the Delaware River in 

 1890, which reportedly passed large numbers 

 of shad for a period of about 10 yr. before 

 the dam was destroyed by ice (New York Con- 

 servation Commission of Fisheries, 1891). 

 Unfortunately, no records were available to 

 indicate the design of this structure. In the 

 early 1900's because of the failure of fish- 

 ways, it was generally thought that shad would 

 not use fish-passage devices. For this reason, 

 no fishway was included in Conowingo Dam, 

 which was completed in 1928 on the Susque- 

 hanna River in Maryland. With the continued 

 decline in production during the I930's, con- 

 servationists explored means of restoring this 

 fish to greater abundance. Successful passage 

 of shad through fishways at Bonneville Dam, 

 completed in 1937 on the Columbia River on 

 the West Coast, brought renewed efforts for 

 workable fishways in Atlantic coast dams. 



TX:^ 



\ 



Figure 30. — Ineffective fishway on a lock and dam. Cape 

 Fear River, N. C. The structure is on the far river 

 shore, and little if any water passes through the trans- 

 portation chamber during the months adult shad would 

 be present. 



One of the aims of the shad investigation 

 begun in 1950 was to determine suitable meth- 

 ods for passing this fish over obstructions. 

 The only fishway in operation on the East 

 Coast which successfully passed shad was in 

 the Essex Company Dam, completed in 1919 

 on the Merrimack River, at Lawrence, Mass. 

 Collins (1951) outlined the distinctive features 

 of this ladder-type fishway, built to pass fish 

 over a 30-ft. rise, and estimated that the 

 number of shad ascending the fishway annually 

 ranged from 1,500 to 3,000. Talbot (1953) 

 presented a summary of observations on the 

 use of the Bonneville fishways by shad and 

 the physical factors associated with passage. 

 The total head of Bonneville Dam, that is, the 

 height to which fish must climb in the fish- 

 ways, ranges from 40 to 60 ft. but most conn- 

 monly is about 50 ft. During the 22-yr. period, 

 1938-59, the average annual passage of shad 

 at this structure was 15,475. In I960, 93,368 

 shad passed the dam (U.S. Army Corps of 

 Engineers, 1959, 1961). 



A system for passing shad was completed 

 at Hadley Falls Dam on the Connecticut River 

 at Holyoke, Mass. in 1952 (fig. 31). The av- 

 erage distance between headwater and tail- 

 water elevation at this structure is 50 ft. This 

 system consisted of an attraction chamber, a 

 pressure lock device which enabled fish to 

 reach the forebay level, and an exit flume. 

 After 3 yr., the pressure lock device was 

 abandoned because it failed to pass migrating 

 fish in sufficient numbers to justify its opera- 

 tion; it was replaced with a trap and a bucket 

 lift. Fish were dip netted manually from the 

 trap to buckets (fig. 32), hoisted to the forebay 

 level, and dumped into the exit flume (fig. 33), 



94 



