Fishery bulletin of the Fish and Wildlife Service - NOAA

STUDIES ON THE STRIPED BASS OF THE ATLANTIC COAST 15
In conclusion, it may be said that there is every evidence that over a long-term
period the abundance of the striped bass of the Atlantic coast has shown a sharp
decline. Dominant year-classes have at times temporarily raised the level of abundance,
but the intensity of the fishery is such that" their effects have been short-lived.
This is well shown in figure 4, where it will be noticed that the return to a state approaching
the normal low abundance usually follows immediately after the appearance
of a dominant year-class in the commercial catch. In the 1934 year-class, however,
the numbers of striped bass reached such enormous proportions that not only
did the 2-year-olds of 1936 dominate the fishery, but the 3-year-olds of 1937 also
formed the main part of the catch. None the less, the sharp decline in numbers of
bass taken in 1937, as compared with those caught in 1936, is clearly evident, and
there can be little doubt that the members of this dominant year-class will be reduced
within a few years—under the conditions of the present intensive fishery—to a point
where they are negligible.- The rate of removal of the different age-groups of the
striped bass by the fishery is shown in some measure by the percentage of returns
of tagged fish. These percentages are shown in tables 17-20, and 22, It is of interest
that the extreme in percentage of recapture is seen in the case of 303 fish (predominantly
3-year-olds) tagged and released at Montauk, Long Island, N. Y., in late
October 1937. Six months later over 30 percent of these tagged fish had been recaptured.
Furthermore, it is not reasonable to expect that the percentage of tag returns
gives a sufficiently great valuation of the rate of removal of the fish of different ages,
for, among other reasons, no reward was offered for the return of tags, and it is undoubtedly
true that many of the marked fish that were captured were never reported.
It is roughly estimated that about 40 percent of the 2-year-olds of 1936 were taken
during their first year in the fishery, and that at least 25-30 percent of the remaining
3-year-olds were caught in 1937. This means that a minimum of 50 percent of the
2-year-olds entering the fishery in the spring of 1936 had been removed by the spring
of 1938, neglecting the effect of natural mortality. It thus becomes clear why dominant
year-classes only raise the level of abundance over short periods, and why, in
spite of the occasional increases in number, the general trend of the annual catch of
striped bass has been downward. Looking to the future, there is no reason to suppose
that the increased abundance caused by the 1934 dominant year-class—huge as it
was—will produce any lasting effect on the stock. It is more probable that the return
to the normally low level of abundance, so characteristic of the years before 1936, will
soon take place, and that only the production of another dominant year-class will raise
the population of striped bass to such unusually high numbers.
SPAWNING HABITS AND EARLY LIFE HISTORY OF THE
STRIPED BASS
It is commonly stated in the standard ichthyological references for the Atlantic
coast that striped bass are anadromqus, spawning in the spring of the year from April
through June, the exact time depending on the latitude and temperature (Smith, 1907,
and Hildebrand and Schroeder, 1928). Most of the statements on the spawning of
this species have been based on a series of papers in which S. G. Worth (1903 to 1912)
discussed the problem of artificial propagation and presented many interesting sidelights
on the various phases of spawning and early life history from his studies at
Weldon, on the Roanoke River, N. C. Although most of the information in Worth's
work is fragmentary, his observations are of value because there has been so little
work on any part of the Atlantic coast to corroborate and amplify his statements.
The work of Coleman and Scofield (1910) and Scofield (1931) on the Pacific coast
indicates that striped bass spawn from April through June in the low-lying delta
country adjacent to Suisun Bay, Calif., where the water borders between brackish
and fresh.
The presence of young fry and small striped bass in the brackish waters of large
rivers of the Atlantic coast offers proof that this is an anadromous species, and the
absence of juvenile and yearling bass along the outer coast indicates that this species
does not undertake coastal migrations until they are close to 2 years old. Thus
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