7921 ‎(2)‎

• UCREFRP Catalog Number: 7921
• Author: Trembly, T. L. and G. A. Gould.
• Title: Opportunities To Protect Instream Flows In Colorado And Wyoming.
• USFW Year: 1987.
• USFW - Doc Type: Biological Report 87‎(10)‎,
• Copyright Material: NO

the Sacramento and San Joaquin River estuary fed mainly on invertebrates
during the first winter and spring, changing to a diet of small fish the
following summer (Stevens 1966). Gomez (1970) studied the food habits of
young-of-the-year in Canton Reservoir, Oklahoma, and found that crustaceans
and insects were a very significant part of the diet of striped bass 50 to
80 mm TL, gizzard shad (Dorosoma cepedianum) larvae were consumed by striped
bass as early as 53 mm TL, and gizzard shad made up 15% of the diet of 66 mm TL
striped bass. Morris and Follis (1978) reported that striped bass over 1-year
old had reduced growth rates as shad (Dorosoma sp.) declined in Lake E.V.
Spence, Texas.
Adults also tend to be opportunistic feeders (Merriman 1941; deSylva
1973), but landlocked populations usually select clupeids or soft-rayed fish
over other available food items. Striped bass in the Santee-Cooper Reservoir,
South Carolina, fed heavily on mayfly nymphs during the spring months, but ate
clupeid fishes almost entirely for the remainder of the year (Stevens 1958).
Gizzard shad was the dominant food item for striped bass in Keystone Reservoir,
Oklahoma (Mensinger 1971; Combs 1978). Ware (1971) found a preponderance of
threadfin shad (Dorosoma petenense) and gizzard shad in the diet of striped
bass 15 cm (6 inches) and larger from Florida lakes. Threadfin shad was the
primary food item, both in frequency of occurrence and total volume, of adults
from the lower Colorado River .(Edwards 1974) and Lake Powell (Persons and
Bulkley 1982). In the Illinois River, Oklahoma, striped bass 5 kg (11 lb) and
larger fed heavily on rainbow trout (Salmo gairdneri) for the first week after
the trout were stocked but gizzard shad made up 75% of their diet by number
thereafter (Deppert and Mense 1979). Threadfin shad and American eel (Anguilla
rostrata) were the major food items in stomachs of juveniles and adults from
the Apalachicola River, Florida (Crateau et al. 1980, 1981). An abundance of
small threadfin shad was considered critical for rapid growth of striped bass
larger than 110 mm TL in Lake Powell (Gustaveson et ai. 1980).
Adults may feed during spawning migrations (Morgan and Gerlach 1950;
Trent and Hassler 1966; Persons and Bulkley 1982), but likely fast during
spawning (Woodhull 1947; Morgan and Gerlach 1950; Hollis 1952; Stevens 1966;
Trent and Hassler 1966; Manooch 1973).
Compared to natural coastal stocks, striped bass introduced into rivers
and lakes likely grow faster, attaining an average length of about 25.4 to
27.9 cm (10 to 11 inches) the first year and 43.2 to 45.7 cm (17 to 18 inches)
the second year (Scruggs 1957; Stevens 1958; Mensinger 1971; Ware 1971;
Erickson et al. 1972). Juveniles, initially introduced into the Colorado
River from California waters, grew an average of about 15.2 cm (6 inches)
during the first year; river-spawned individuals grew to a mean of about
20.3 cm (8 inches} their first year (Edwards 1974). The mean fork length of
age I and II striped bass from the Apalachicola River, Florida, was calculated
to be 15.6 and 30.7 cm (6.1 and 12.1 inches), respectively (Crateau et al.
1981; Wooley and Crateau 1983). The length of striped bass from the Atlantic
Coast at age I was roughly 12 cm (4.7 inches) and about 22 cm (8.7 inches) at
age II (Merriman 1941). After age IV to VI, females grow faster than males
(Robinson 1960; Mansueti 1961; Bason 1971).
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