Download Species Description, Current Range, and Habitat

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White Bass
Morone chrysops
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Striped Bass
Morone saxatilis
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Species Description and Current Range
White Bass and Striped Bass are members of the temperate true bass family. The species name
for White Bass, chrysops, means golden eye, a defining characteristic of White Bass. The species name for Striped Bass, saxatilis, means ‘among the rocks’ referring to preferred Striped
Bass spawning habitat. The only documented population of White Bass in the PNW is in
Southwest WA, near Vancouver. Striped Bass were introduced over a century ago to the Pacific
Coast where their range now extends from Northern Mexico to BC. The largest populations of
Striped Bass are in San Francisco Bay, CA and Coos Bay and the Umpqua River in OR. Smaller populations exist in the Columbia River and along Vancouver Island.
White Bass live only in large freshwater lakes and rivers. Striped Bass spend their whole lives
in freshwater when living in landlocked lakes, but can be anadromous. Landlocked adult
Striped Bass reach 7-14 kg with saltwater fish growing even larger. White Bass weigh only
about 1 kg. Thirty to fifty days after hatching, Striped Bass resemble adults (only smaller). Juvenile Striped Bass and adult White Bass are difficult to distinguish: both are silver with longitudinal dark stripes and a double dorsal fin comprising spiny and soft portions. The best way to
distinguish the two species is to look in their mouths. White Bass have a single heart shaped
tooth patch and Striped Bass have two distinct and parallel tooth patches on the back of their
tongue. Wipers, a White Bass/Striped Bass infertile hybrid artificially propagated since 1965,
have been introduced into lakes and reservoirs throughout the US.
Impacts to Communities and Native Species
True bass are predatory with healthy appetites for smaller fish, and are responsible for the decline of native species of fish throughout their introduced range. The population of Striped Bass
in Coos Bay, OR steadily increased throughout the 1950s and 60s, consuming hundreds of
thousands of juvenile salmon, contributing to the decline of salmon.
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Individual Species Accounts – 100 Worst Invasives
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Control Methods and Management
Both of these are sport fish and are managed as game species. In OR, Striped Bass have not
been restocked in areas where they were previously abundant to lessen predation on native fish.
Paradoxically, there are still strict daily catch limits in OR (what are the catch limits?) to ensure
the future of the Striped Bass population.
Life History and Species Overview
Striped Bass adults spawn in early summer in freshwater rivers with rocky habitat and swiftly
moving water. Eggs must stay suspended in the water column to survive and hatch out in two to
three days. Larval Striped Bass float downstream and stay in the estuarine nursery habitat for 2
years before moving along the coast and returning to streams to spawn. Females, visibly larger
than males, mature at age 4 and males at age 2. Most Striped Bass spawn yearly, and have a
maximum lifespan of 10-12 years. Larval Striped Bass feed on zooplankton, progressing to a
diet of fish, crabs and other invertebrates. With the construction of reservoirs came the discovery that populations of Striped Bass trapped in landlocked lakes completed their entire life cycle in freshwater. This prompted introduction of Striped Bass into reservoirs and lakes for sport
fishing.
Striped Bass have been an important commercial fish in the US since colonial times. The residents of Plymouth used Striped Bass as a food source as early as 1623. Striped Bass were in
high demand in the MA Bay Colony, and by 1639 some of the earliest conservation measures
were passed, banning the sale of Striped Bass as fertilizer. Legislation in 1776 outlawed the
sale of Striped Bass in winter months, but Striped Bass populations continued to decline
throughout the next two centuries from overfishing and habitat destruction. Declining stocks on
the East Coast prompted the passage in 1980 of the Striped Bass Conservation Act with limits
and closures. Striped Bass stocks have largely been rebuilt; however active management of the
species remains in place.
White Bass are short-lived schooling fish found in large lakes and rivers. They spawn in lakes
and rivers over sandy or rocky bottoms. The eggs are released into the water, sink and adhere to
the bottom, then hatch out in about two days. Young White Bass grow quickly, up to 20 cm
long in the first year, with a maximum length of 30-38 cm. Fish are the preferred food of White
Bass but they will eat invertebrates when fish are unavailable. They generally mature at age
two and have a lifespan of 3-4 years.
History of Invasiveness
Populations of Striped Bass on the west coast descend from fish transported cross-country on
the intercontinental railroad. In 1879, 132 Striped Bass traveled by train from NY to CA in
milk jugs and the survivors were released into San Francisco Bay. Three years later 300 more
fish made the same journey. After release, the Striped Bass migrated north and by 1914 Striped
Bass had spread to Coos Bay, OR and are now found from BC to Baja CA. The White Bass introduction in WA is not well documented, possibly occurring in the 1960s.
Other Sources of Information: 1, 7, 15, 16, 18
References: 5, 6, 22, 28, 30
Author: Katie Barnas, NMFS, Northwest Fisheries Science Center, Seattle WA 981?? USA
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Individual Species Accounts – 100 Worst Invasives