The Nonindigenous Occurrences section of the NAS species profiles has a new structure. The section is now dynamically updated from the NAS database to ensure that it contains the most current and accurate information. Occurrences are summarized in Table 1, alphabetically by state, with years of earliest and most recent observations, and the tally and names of drainages where the species was observed. The table contains hyperlinks to collections tables of specimens based on the states, years, and drainages selected. References to specimens that were not obtained through sighting reports and personal communications are found through the hyperlink in the Table 1 caption or through the individual specimens linked in the collections tables.

Morone americana × mississippiensis
Morone americana × mississippiensis
(White Perch × Yellow Bass)
Native Hybrid

Copyright Info
Morone americana × mississippiensis

Common name: White Perch × Yellow Bass

Native Range:
Hydrologic Unit Codes (HUCs) Explained
Interactive maps: Point Distribution Maps

Nonindigenous Occurrences: Hybrids of M. americana and M. mississippiensis were first found in 2000 in the middle Illinois River, Illinois (Irons et al. 2002).  The following year another 32 specimens were collected.

Table 1. States with nonindigenous occurrences, the earliest and latest observations in each state, and the tally and names of HUCs with observations†. Names and dates are hyperlinked to their relevant specimen records. The list of references for all nonindigenous occurrences of Morone americana × mississippiensis are found here.

StateFirst ObservedLast ObservedTotal HUCs with observations†HUCs with observations†
IL200020051Lower Illinois-Lake Chautauqua

Table last updated 5/9/2022

† Populations may not be currently present.

Means of Introduction: White perch (M. americana) invaded the native range of yellow perch via the Chicago Shipping Canal from the Great Lakes, where it is also introduced.  It gained access to the Great Lakes via the Erie Canal system in New York (see account for white perch).

Status: Established in the middle Illinois River.

Impact of Introduction: Hybridization and competition may represent another threat to the already dwindling yellow bass of that region (Irons et al. 2002).

References: (click for full references)

Irons, K.S., T.M. O'Hara, M.A. McClelland, and M.A. Pegg.  2002.  White perch occurrence, spread, and hybridization in the middle Illinois River, upper Mississippi River system.  Transactions of the Illinois State Academy of Science 95(3):207-214.

Other Resources:
Fact Sheet for Morone americana - USGS Nonindigenous Aquatic Species Database

Fact Sheet for Morone mississippiensis - USGS Nonindigenous Aquatic Species Database

Author: Fuller, P.

Revision Date: 5/9/2019

Peer Review Date: 8/20/2004

Citation Information:
Fuller, P., 2022, Morone americana × mississippiensis: U.S. Geological Survey, Nonindigenous Aquatic Species Database, Gainesville, FL, https://nas.er.usgs.gov/queries/FactSheet.aspx?SpeciesID=2395, Revision Date: 5/9/2019, Peer Review Date: 8/20/2004, Access Date: 5/16/2022

This information is preliminary or provisional and is subject to revision. It is being provided to meet the need for timely best science. The information has not received final approval by the U.S. Geological Survey (USGS) and is provided on the condition that neither the USGS nor the U.S. Government shall be held liable for any damages resulting from the authorized or unauthorized use of the information.


The data represented on this site vary in accuracy, scale, completeness, extent of coverage and origin. It is the user's responsibility to use these data consistent with their intended purpose and within stated limitations. We highly recommend reviewing metadata files prior to interpreting these data.

Citation information: U.S. Geological Survey. [2022]. Nonindigenous Aquatic Species Database. Gainesville, Florida. Accessed [5/16/2022].

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