Aplodinotus grunniens
Rafinesque, 1819
Common Name:
Freshwater Drum
Synonyms and Other Names:
bubbler, croaker, gaspergou, gou, gray bass, grinder, grunt, lake drum, sheepshead, silver bass, thunder pumper
Identification:
Laterally compressed, silver, deep bodied fish. Has a long dorsal fin relative to its total length containing a deep notch. Mouth is sub-terminal with a blunt rounded snout (Goldstein and Simon 1999). Anal fin has seven soft rays and two spines, with the first being much shorter than the second. Dorsal fin usually has 10 spines and 29 to 32 rays. Possesses 20 to 24 gill rakers (Knapp 1953). A unique feature of these fish is that the lateral line extends into their rounded caudal fin. Scales are ctenoid and the number of scales on the lateral line ranges from 49 to 53 (Hubbs et al. 1991). Except for general coloration and the absence of a dark spot on the caudal fin, this species closely resembles its saltwater relative, the Red Drum ( Trautman 1981; Robison and Buchanan 1988; Etnier and Starnes 1993; Ross and Brenneman 2001; MN DNR 2005; TPWD 2009).
Size:
95 cm maximum length (IGFA 2001), 45 cm common length (Frimodt 1995).
Native Range:
East of the Rocky Mountains in the St. Lawrence-Great Lakes, Hudson Bay, and Mississippi River basins from Quebec to northern Manitoba and southern Saskatchewan in Canada and south to the Gulf of Mexico. Present in the Rio Grande and other Texas rivers, and Gulf Coast drainages from Mobile Bay, Georgia and Alabama, through eastern Mexico to the Rio Usumacinta system in Guatemala (Barney 1926; Page and Burr 1991). This species is native and abundant in Lakes Michigan, Huron, Erie, and Ontario (Richardson 1831; Dekay 1855; Bean 1903; Forbes and Richardson 1908; Halkett 1913; Cudmore-Vokey and Crossman 2000; Roth et al. 2013).
Great Lakes Nonindigenous Occurrences:
The first recorded non-indigenous U.S. occurrence of this species was in 1892 in the Fox River drainage, Kane County, Illinois where it was initially stocked for sport fishing (Bean 1892). In 1996 and again in 2006, it was reported that Freshwater Drum populations were established near the Hudson River estuary in New York (Mills et al. 1996; Schmidt and Lake 2006; Schmidt et al. 2007). The species also was introduced into the Youghiogheny river system in Pennsylvania in 1983, where it was stocked for sport but failed to establish (Hendricks et al. 1983). Two Freshwater Drum were then collected in 1947 from the Moen's Lake chain in Oneida County, Wisconsin, in the upper Wisconsin River drainage, also stocked for sport fishing (Becker 1983). There are no other records of Freshwater Drum from the upper Wisconsin River, and the species is considered native farther downstream near and below the Portage area (Becker 1983). Great Lakes (outside of native range)
Barney (1926) reported no published records of this species existed for Lake Superior, which is therefore considered outside the native range. First collected from Lake Superior in the 1970s and is currently confirmed as overwintering and reproducing in local portions of the St. Louis estuary (Cudmore-Vokey and Crossman 2000; Peterson et al. 2011).
Table 1. Great Lakes region nonindigenous occurrences, the earliest and latest observations in each state/province, 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 Aplodinotus grunniens are found here.
Full list of USGS occurrences
Table last updated 11/2/2024
† Populations may not be currently present.
Ecology:
Aplodinotus grunniens is the only member of its family in North America to occur completely in freshwater habitats. It typically inhabits the bottom of medium to large rivers and lakes up to about 40 to 60 foot depths (Scott and Crosman 1973; Etnier and Starnes 1993). It is tolerant of both clear and turbid conditions (Fremling 1980). Growth rate is also positively correlated with high magnitude flow events (Jacquemin et al. 2015). Individuals have been observed to become stressed when water temperature exceeds 25.6°C and when dissolved oxygen concentrations remain low over an extended period (Priegel 1967). The adult diet consists mainly of immature insects, crayfish, minnows, amphipods, and mollusks, while young fish feed on zooplankton (Daiber 1952; Fremling 1980; Etnier and Starnes 1993). The Freshwater Drum often roots around in the substrate or moves rocks on the bottom to dislodge its prey and will feed throughout all hours of the night (Priegel 1967). It is also likely the exclusive host fish for the freshwater mussels: Ellipsaria lineolata, Leptodea fragilis, Leptodea leptodon, Potamilus alatus, and Truncilla truncata, and is a suitable host for Potamilus ohiensis and Truncilla donaciformis (Chong et al. 2018; Sietman et al. 2018). Spawning occurs in open water during May and June when water temperatures reach 18 to 26°C ( Wrenn 1969; Swedberg and Walburg 1970; Fremling 1980 ). Large females are capable of laying up to 600,000 positively buoyant eggs (Wrenn 1969; Fremling 1980), which float at the surface until they hatch roughly 24 hours later in warmer waters (Swedberg and Walburg 1970). Sexual maturity is reached after 4 to 6 years, with individuals measuring at least about 20 cmin length (Diaber 1953; Priegel 1969; Wrenn 1969). The maximum reported age of this species is 13 years (Altman and Dittmer 1962), but on average, it lives for 6–8 years (Etnier and Starnes 1993; Ross and Brenneman 2001).
Means of Introduction:
Freshwater Drum was stocked in the late 1800s in Illinois lakes as a sport fish (Bean 1892), and later in Colorado in the 1950s for the same reason (Everhart and Seaman 1971). It was accidentally stocked in two Wyoming reservoirs in the early 1990s (Hubert 1994). The two fish reported from the upper Wisconsin drainage in Wisconsin were likely the result of fish rescue and transfer operations from the Mississippi River in the 1930s (Becker 1983). Great Lakes
Prior to the 1970s, discovery of this species in Lake Superior was considered highly likely, as it was already present in all of the other Great Lakes, including Lake Huron to which Lake Superior is directly connected (Richardson 1831; Barney 1926). Dispersal through the canal and lock system from Lake Huron is thought to be the primary pathway of introduction (N. Mandrak, Fisheries and Oceans Canada, pers. comm.).
Status:
Established in Lake Superior (Peterson et al. 2011; Roth et al. 2013). Established in Colorado; reported in Illinois, Wisconsin, and Wyoming. Extirpated in Pennsylvania (Hendricks et al. 1983). Great Lakes
Native and abundant in Lakes Michigan, Huron, Erie, and Ontario. Reproducing and overwintering at self-sustaining levels have been recorded in the St. Louis River. With the colonization of Lake Superior, this species is now widespread in the Great Lakes.
Great Lakes Impacts:
Current research on the environmental impact of Aplodinotus grunniens in the Great Lakes outside of its native range is inadequate to support proper assessment. Potential:
As Aplodinotus grunniens are already present and abundant in all of the other Great Lakes, any negative environmental effect of their introduction on Lake Superior is likely to be minimal. However, in 2005, Freshwater Drum infected with Viral Hemorrhagic Septicemia (VHS) were collected from the Bay of Quinte, Lake Ontario (Wren and Lee 2006). The following summer, infected fishes were collected from Lake St. Clair, Lake Erie, and Lake Ontario (USDA 2006). There is no evidence that this virus has yet been transported into Lake Superior by means of A. grunniens, but research has suggested that there is high potential for the spread of VHS with baitfish as a vector (Meyers et al. 1994).
There is little or no evidence to support that Aplodinotus grunniens has significant socio-economic impacts in the Great Lakes outside of its native range.
Aplodinotus grunniens has little or no negative socioeconomic effect on any of the Great Lakes in which it is a native inhabitant, so any negative effect on Lake Superior is likely to be minimal.
Aplodinotus grunniens has a moderate beneficial effect in the Great Lakes outside of its native range.
Potential:
Aplodinotus grunniens constitutes a small portion of the commercial catch in the Great Lakes, serves as a good baitfish, and is commonly fished for sport. These factors imply that it may have some beneficial effects in Lake Superior (Wisconsin Sea Grant 2002). In addition, the inner ear bones, or otoliths, of this species very closely resemble ivory, and are prized as jewelry pieces and charms in many regions today (Knapp 1953).
It also is known to consume the nonindigenous mussel Dreissena polymorpha (Zebra mussel) in the Great Lakes and may contribute to regulating Dreissena polymorpha populations in Lake Champlain (French et al. 1996; Morrison et al. 1997; Watzin et al. 2008). However, size limitation on Dreissena polymorpha consumption by Aplodinotus grunniens may reduce its potential as a biological controller in the Great Lakes (French et al. 1995).
Management:
Freshwater Drum is considered native to all the Great Lakes except Lake Superior, where it has only recently invaded (1970s) and become established (Cudmore-Vokey and Crossman 2000) but is still considered rare. They are also native to the Mississippi River drainage and considered native in each of the Great Lakes states. Thus they are managed principally as a native sportfish throughout the Great Lakes region.
Remarks:
In Wisconsin, there are no other records of Freshwater Drum from the upper Wisconsin River; the species is considered native farther downstream near and below the Portage area (Becker 1983).
This species earned part of its Latin name, grunniens, due to the odd grunting noises it is capable of generating. These noises are produced by a set of muscles located in the body cavity that vibrate against the swim bladder. When removed from the water, they produce a frog-like croaking sound.
References
(click for full reference list)
Author:
Fuller, P., K. Dettloff, and R. Sturtevant
Contributing Agencies:
Revision Date:
8/3/2021
Peer Review Date:
8/3/2021
Citation for this information:
Fuller, P., K. Dettloff, and R. Sturtevant, 2024, Aplodinotus grunniens Rafinesque, 1819: U.S. Geological Survey, Nonindigenous Aquatic Species Database, Gainesville, FL, and NOAA Great Lakes Aquatic Nonindigenous Species Information System, Ann Arbor, MI, https://nas.er.usgs.gov/queries/GreatLakes/FactSheet.aspx?Species_ID=946, Revision Date: 8/3/2021, Peer Review Date: 8/3/2021, Access Date: 11/2/2024
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.