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Striped Bass Life Cycle
Spawning
- Spawning is triggered by an increase in water temperature and generally occurs in April,
May and early June.
- Female striped bass can mature as early as age 4, however, it takes several years
(age 8 or older) for spawning females to reach full productivity. Once a mature female
broadcast her eggs in the current, they are fertilized by milt ejected from a mature male
(age 2 or 3). Depending on the size of the female, one female can lay from 14,000 (3
pounder) to 3,000,000 eggs (10 pounder ).A thirty-pound female is capable of
producing as many as five million eggs. In a fast moving current, the eggs hatch out at a
considerable distance downstream from the spawning place. At the time of hatching, the
tiny transparent fish, less than ¼ inch long emerges with a heavy yolk sac attached. It
derives nourishment from this sac. The fry at this stage is at the mercy of the
water currents. Within four to five days, the yolk sac is absorbed and the fry begins to
swim and feed on small crustaceans (Scruggs, 1954).
- The fertilized eggs need to drift downstream with currents to hatch into larvae. A flow
velocity in the river of approximately one-foot per second is required to keep the eggs
afloat. If the egg sinks to the bottom, its chances of hatching are reduced because the
sediments reduce oxygen exchange between the egg and the surrounding water. This need for
flowing water to hatch is the reason Striped Bass don't naturally reproduce in Reservoirs
and lakes across America and must be stocked by the Fisheries Department of each state
where Striped Bass are located.
- Striped Bass males usually reach sexual maturity at two years. Females can reach
maturity at four years. Nearly all of the females are mature at five years of age when
they reach a weight of six pounds or a length of twenty-three inches.
- Some rivers, the Arkansas River is one, do have a naturally reproducing
Striped bass population.
Hatching and Larval Stages
- Striped bass eggs hatch 29 to 80 hours after fertilization, depending on the water
temperature. The larvae's survival depends primarily upon events during the first three
weeks of life.
- Eggs and newly hatched larvae require sufficient turbulence to remain suspended in the
water column; otherwise, they will settle to the bottom and be smothered.. Larvae at this
point have an average size of 3.1 mm.
- The larvae begin feeding on microscopic animals during their downstream journey.
- The mouth forms in two to four days, and the eyes are unpigmented.
- The larvae are nourished by a large yolk mass. Eggs produced by female stripers weighing
10 pounds or more contain greater amounts of yolk and oil reserve and have a greater
probability of hatching.
- Typically striped bass larvae begin feeding on their own about five days after hatching,
depending on water temperature.
Food
- Striped bass larvae feed primarily on zooplankton (e.g. Copepoda,
Cladoceracopepods (crustaceans) in both larval and mature stages, and cladocerans (water
fleas).
- Juvenile stripers eat insect larvae, larval fish, mysids (shrimplike crustaceans) and
amphipods (tiny scavenging crustaceans that lack a carapace and have laterally flattened
bodies).
- Adults are piscivorous, or fish-eaters. soft ray fish like shad (Herring Family) making
up their primary diet.
Habitat
- Mature stripers in fresh water lakes are found in open areas using deeper channels as
paths to feeding grounds on flats, points and humps.
The Fishery
On the east coast the principle gear used in the commercial striped bass fishery
included pound nets, haul seines, and drift, anchor and stake gillnets.
- The recent Atalantic status of the striped bass fishery tells a relative success story,
after more than 10 years of steep decline. Commercial landings in Maryland and Virginia
generally increased from the early 1930s, culminating in a record commercial catch in 1973
of 14.7 million pounds. Thereafter the striper harvest fell steadily to 1.7 million pounds
by 1983. Sport fishermen reported a similar pattern. The decline translated into a loss of
about 7,000 jobs and $220 million in 1980.
- In response to this dramatic downturn, Congress passed the Atlantic
Striped Bass Conservation Act in 1984. Maryland and Delaware imposed fishing moratoria
from 1985 to 1989, and Virginia imposed a one-year moratorium in 1989. Although the
fishery reopened in 1990 following three successful spawning years, it remains tightly
restricted.
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