Morone mississippiensis Jordan and Eigenmann, 1887
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Basis for Listing
The yellow bass is uncommon in Minnesota, where it reaches the northern limits of its rangewide distribution in the Mississippi River. The species has been reported sporadically in the Mississippi River from Pool 8 up to Lake Pepin (Hatch et al. 2003). Dams prevent or curtail the northward migration of this southern species. Given its limited distribution in the state, the yellow bass was listed as a special concern species in 1984.
The yellow bass is silvery-yellow in color overall with dark green on its back. It has a compressed body with 6-9 dark horizontal stripes on the sides. Its soft dorsal fin and spinous dorsal fin are connected, and its anal fin has 3 spines and 9-10 soft rays. The back of its tongue lacks teeth (Hatch et al. in preparation). The stripes on the sides of its body are broken and offset above the front of the anal fin, distinguishing it from white bass (Morone chrysops). The yellow bass can grow up to 45.7 cm (18 in.) in total length, but rarely reaches lengths greater than 30 cm (11.8 in.). The largest specimen from Minnesota was 38.9 cm (15.3 in.) long.
Yellow bass occur in large rivers and their backwaters, impoundments, and sloughs. Historically in Minnesota they occurred in river lakes such as Lake Pepin, but today they are only known to occur in the Mississippi River south of Red Wing.
Biology / Life History
Little is known about the life history of the yellow bass in Minnesota. It breeds in the spring, most actively when water temperatures are 20°C-22°C (68°F-72°F). Eggs are fertilized in the open and get no care. Its diet includes mostly invertebrates and small fishes. Adults at times will eat small yellow bass and gizzard shad (Dorosoma cepdianum) along with insects (Hatch et al. in preparation). The species sexually matures at age 3, and few live beyond 5 years.
Conservation / Management
The yellow bass is a rare fish in Minnesota and it is vulnerable to impacts to its river environment. Furthermore, dams prevent or curtail the northward migration of this southern species, limiting its abundance in the state. Other common names for the yellow bass include bar fish, black striped bass, brassy bass, gold bass, streaker, striped bass, striper, yellow bass, and yellow belly.
Conservation Efforts in Minnesota
The Minnesota DNR Division of Ecological Services received a State Wildlife Grant to conduct surveys for rare fish species in the Mississippi River from the Twin Cities to the Iowa border. These surveys were conducted from 2006-2008 (Schmidt and Proulx 2009), and while the yellow bass was a targeted species, none were found. Additional research needs for the yellow bass in Minnesota include life history studies, genetic analysis, identification of habitat guilds, and identification of limiting factors and opportunities for fish passage around dams.