18 



FISHERY BULLETIN OF THE FISH AND WILDLIFE SERVICE 



this river. The capture of only three juvenile striped bass, however, is significant, 

 and probably indicates that striped bass spawn in the Parker River. Added evidence 

 that this is a spawning area is seen in the fact that striped bass are known to winter in 

 this river, as is shown by their capture through the ice by bow-net fishermen. It is 

 considered likely that this is an example of an isolated spawning area in northern 

 waters, supported at least in part by a resident population, and possibly added to by 

 migrants from the south in exceptional years. Although this is the northernmost 

 point from which juveniles have been definitely reported in recent years, there can be 

 no doubt that they were commonly taken in the coastal rivers of the Gulf of Maine in 

 old times (Bigelow and Welsh, 1925), and there is good reason to believe that other 

 isolated spawning areas still exist north of Cape Cod. 



Another area in which juvenile striped bass were taken was in the Delaware River, 

 near Pennsville, N. J. On November 8, 1937, the author was present when the game 

 protectors for the State of New Jersey Board of Fish and Game Commissioners took 

 104 small striped bass from the intake wells of a large power plant on the Delaware 

 River, where fish of all sorts are regularly trapped against the screens by the strong 

 flow of water, and are removed and liberated in other regions. A length-frequency 

 curve of this material is shown in figure 1 1 . The examination of scales from these fish 

 showed that the bulk of this sampling was composed of yearlings, and that only a few 

 juveniles from about 9.0-12.5 cm. long were present. It is considered probable, there- 

 fore, that the Delaware River region, including some of the smaller streams that enter 

 Delaware Bay, forms another area in which striped bass spawn. 



LENGTH FREQUENCIES OF 

 STRIPED BASS TAKEN IN 

 DELAWARE RIVER NEAR 

 PENNSVILLE, N J , 

 NOV. 8, 1937 



L E N G T H 



Figure 11.— Length-frequency curve of juvenile and yearling striped bass taken in the Delaware River, near Pennsville, N. J., on 

 Nov. 8, 1U37. The number of fish included in this graph is 104. The data have been smoothed by threes (see Table 9 for original 

 measurements). 



It has long been known from the observations of Worth (1903 to 1912) at Weldon, 

 N. C, that striped bass spawn in the Roanoke River. The main observations on the 

 eggs and larvae of the striped bass that are recorded in the literature for the Atlantic 

 coast are taken from Worth's papers, and were made during the time that he con- 

 ducted a hatchery at this point. Bigelow and Welsh (1925) sum up the available 

 information as follows: 



The eggs (about 3.6 mm. in diameter) are semi-buoyant — that is, they sink but are swept up 

 from the bottom by the slightest disturbance of the water — and this is so prolific a fish that a female 

 of only 12 pounds weight has been known to yield 1,280,000 eggs, while a 75-pound fish probably 

 would produce as many as 10,000,000. The eggs hatch in about 74 hours at a temperature of 58°; 

 in 48 hours at 67°. 



In recent years the hatchery at Weldon has again resumed operations, thus affording 

 an excellent chance for the study of the eggs and larvae of the striped bass. Others 

 have already accumulated detailed information on this subject (Pearson, 1938), and 

 the following material (from data collected in 1937 and 1938) included herewith, is 

 therefore nothing more than a brief account of some of the more interesting highlights 

 of the spawning and early life history of the striped bass. 



Spawning in the Roanoke River normally occurs in April and May, although 

 occasionally there are a few stragglers that appear as late as June. It is probable 

 that spawning takes place over a good stretch of the river from Weldon down. (Weldon 

 is over 75 miles by river from Albemarle Sound.) At Weldon the river flows about 

 4 miles an hour, and is approximately 100 yards wide. Water samples taken on 

 March 29, 1937, showed the chlorinity to be less than 5 parts per million (fresh water), 

 the pH 7.7, and the alkalinity 53.1 estimated as milligrams of bicarbonate per liter. 



