Ambloplites rupestris

History of Spread

Ambloplites rupestris (Rock Bass) is native to the St. Lawrence - Great Lakes, Hudson Bay and Mississippi drainages, Quebec-Saskatchewan, south to north GA, north AL and MO (Page and Burr 1991). It was introduced by United States Fish Commission (USFC) starting in 1889 to Atlantic drainages and some western states. Shipments and stocking by the United States Fish Commission continued to 1936. Many state agenicies continue to stock this fish.

A. rupestris was introduced in Atlantic drainages from NH south to the Roanoke River in NC-VA, in the Missouri and Arkansas River drainages in MO, AR, KS, and OK, and in some western states including CA, WA, CO and WY (Hardy 1978, Fuller et al. 1999; Page and Burr 1991). On the East Coast, Rock Bass reached the Hudson River estuary by 1843, via the Erie Canal (Mills et al. 1997). On the West Coast, stockings in the San Francisco Bay drainage in 1874 and later were unsuccessful (Cohen and Carlton 1995), but Rock Bass are established in the Chehalis River drainage in WA (Fuller et al. 1999). At present, this species has introduced to non-native drainages in 23 states, and is established in most of those locations (Fuller et al. 1999). They have aso been introduced to England, France, Mexico, and Puerto Rico, but are known to be established only in France (Lever 1996).

In the Chesapeake Bay drainage, A. rupestris was introduced in PA by Pennsylvania Fish Commission (PFC) before 1880 (Creveling 1881). In VA (and probably also in southern MD) most stockings on the Coastal Plain and lower Piedmont were unsuccessful, probably due in part to high summer temperatures, turbidity and siltation (Jenkins and Burkhead 1993).

James, York, Rappahannock Rivers- Ambloplites rupestris was stocked in 1887-1902, mostly in the Coastal Plain and the lower Piedmont, but these low-elevation introductions seem to have been unsuccessful. The first verified collections occurred in 1928-1944, but these captures were all above Fall-Line, and mostly in upper Piedmont (Jenkins and Burkhead 1993).

Potomac River- Ambloplites rupestris was stocked by the USFC in 1887-1908. The first verified record is 1911 (Jenkins and Burkhead 1993). By 1916, it was 'not uncommon' in the C&O canal at Seneca Creek (Montgomery County, MD), above the Fall-Line (Radcliffe and Welsh 1916). Jenkins and Burkhead's map shows no captures below the Fall Line.

Patuxent River - Two hundred A. rupestris were planted at Sandy Springs 1897 on the nontidal river (Ravenel 1900). Ambloplites rupestris is 'a Piedmont plateau species', and occurs in reservoirs near the headwaters of the Patuxent, but is not found in the estuary (Mansueti 1950).

Susquehanna River - A. rupestris was stocked by the PFC before 1880, but the locations were not specified (Creveling 1881). 'Its existence in the Susquehanna has been known for about twenty years' (Bean 1893). A. rupestris were found 'in fair numbers at most stations' along the river in PA (Bielo 1963). A specimen was collected at Conowingo Dam in 1949 (U.S. National Museum of Natural History 2001), but A. rupestris had probably reached the tidal river long before then.

Upper Bay- A. rupestris were not collected in early upper Bay surveys (Fowler 1917; Fowler 1933; Hildebrand and Schroeder 1928; Radcliffe and Welsh 1917), but were found below Conowingo Dam (McKeown 1984) and on Susquehanna Flats (Howarth et al. 1960). A collection was made from Worton Point, south of Sassafras River mouth (Musick 1972a), but this fish is apparently only occasional in the upper Bay.

Delaware River - Introductions of A. rupestris were made in 1890-1904, 1922, and 1927 (Raasch and Altemus 1991). It is considered an estuarine resident in tidal freshwater by Horwitz (1986), but apparently is rare.

History References - Bean 1893; Bielo 1963; Cohen and Carlton 1995; Cope 1879; Elser 1960; Fowler 1917; Fowler 1933; Fuller et al. 1999; Hardy 1978; Hildebrand and Schroeder 1928; Horwitz 1986; Jenkins and Burkhead 1993; Lever 1996)Mansueti 1950; McKeown 1984; Mills et al. 1997; Musick 1972a; Page and Burr 1991; Raasch and Altemus 1991; Radcliffe and Welsh 1916; Ravenel 1900; Smith and Bean 1898; U.S. National Museum of Natural History 2001

Invasion Comments