Fishery bulletin of the Fish and Wildlife Service - NOAA

ABSTRACT
The results of an investigation of the striped bass (Roccus saxalihs) of the Atlantic coast,
from April 1, 1936, to June 30, 1938, are discussed and the systematic characters of the
species described in detail on the basis of the literature and material afforded by fin-ray,
scale, and vertebral counts, and by measurements on more than 350 individuals.
Studies on the fluctuations in abundance of this species over long-term periods show
that there has been a sharp decline in numbers. Dominant year-classes have at times
raised the level of abundance, but the intensity of the fishery is such that their effects have
been short lived. The dominant year-class of 1934 was the largest to be produced in the
past half century, although the parental stock was probably as low as it has ever been.
There is a good correlation between the production of dominant year-classes of striped
bass and below-the-mean temperatures during the periods before, of, and immediately
after the main spawning season.
The striped bass is strictly coastal in its distribution from the Gulf of St. Lawrence
to the Gulf of Mexico, is anadromous, and spawns in spring. Sex ratios in northern waters
show that males seldom make up more than 10 percent of the population, while in waters
farther south the sex ratios are not so disproportionate. Females first mature as they
become 4 years old, males as they become 2 years old. This difference in age at maturity
may account for the small percentage of males in northern waters, for the time of the spawning
season in the South coincides with the ffme of the spring coastal migration to the North,
which is made up mainly of immature females. The age and rate of growth have been
studied by scale analysis and the average sizes of the different age groups, and the growth
has been calculated to the eleventh year.
Striped bass (3,937) have been tagged, and returns have shown that there is a striking
migration to the North in spring, and to the South in fall. The population in northern
waters in summer remains static. These migrations do not occur until the bass become
2 years old, and have their greatest intensity off the southern New England and Long Island
shores. There is little encroachment by the stock in the Middle Atlantic bight on the
populations in the North or South.
The available evidence from general observation, tagging, and scale analysis points
to the conclusion that the dominant 1934 year-class originated chiefly in the latitude of
Cheasapeake and Delaware Bays, and that those fish born as far south as North Carolina
contribute directly only a relatively small fraction to the population summering in northern
waters.
Stomach-content analyses show that bass are universal in their choice of food, a large
variety of fishes and crustácea forming the main diet. It is suggested that the increased
bulk and availability of Menidia menidia notata in Connecticut waters late in summer and
early in fall are responsible for the increase in, or maintenance of the growth rate of striped
bass in this region despite the sharp drop in water temperature at this time.
The parasites of the species are discussed and several new host records listed. It is
suggested that the bilateral cataracts in a high percentage of individuals bass in the Thames
River, Connecticut, are the result of a dietary deficiency.
The decline in abundance of the striped bass of the Atlantic coast over long-term periods
and its causes are discussed from a theoretical point of view, and it is pointed out that the
present practice of taking a large proportion of the 2-year-olds annually is apparently not
an efficient utilization of the supply. It also is pointed out that both the fishery and the
stock would probably benefit from the protection of these fish until 3 years old, at which
time the average individual length is 41 cm. (16 inches), measured from tip of lower jaw
to fork of tail.
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