Invasion HistoryFirst Non-native North American Tidal Record: 1971
First Non-native West Coast Tidal Record: 1979
First Non-native East/Gulf Coast Tidal Record: 1971
General Invasion History:
Blue Catfish (Ictalurus furcatus) are native to Mississippi and Gulf of Mexico drainages north to Pennsylvania and South Dakota, south to the Gulf Coast (Alabama to the Rio Grande basin and Soto La Marina basins in New Mexico, Texas, and Mexico) (Page and Burr 1991; Froese and Paul 2018). These fish have been stocked on the Atlantic Slope from Georgia to Virginia, and have colonized estuaries in Maryland, with one record in Delaware. In the interior, they have been introduced to Arizona, Colorado, Idaho, western Washington and Oregon (Lee et al. 1980; Page and Burr 1991; Fuller et al. 1999; USGS Nonindigenous Aquatic Species Program 2018). They were introduced to the southern California in 1969. They were first caught in the San Francisco Bay watershed in 1978 and are established but rare in the Delta (Cohen and Carlton 1995; Dill and Cordone 1997).
North American Invasion History:
Invasion History on the West Coast:
The first stocking of Blue Catfish in California involved a batch of 1755 fish introduced to Lake Jennings, in San Diego County, by the California Department of Fish and Game. The justifications were to provide biocontrol of the Asian freshwater clam Corbicula fluminea, and to provide trophy-sized fish for anglers. Since then, Blue Catfish were introduced to many watersheds in Southern California (Dill and Cordone 1997). In 1978, one fish was caught in the San Joaquin River, and in Clifton Court Forebay in 1986. These fish may have escaped from an aquaculture operation in the Central Valley (Dill and Cordone 1997). Blue Catfish are established but rare in the Sacramento-San Joaquin Delta (Cohen and Carlton 1995; USGS Nonindigenous Aquatic Species Program 2018). In 2017, an 830 mm fish was caught in Clear Lake, in the Sacramento River basin (http://www.foxnews.com/great-outdoors/2017/07/12/monster-catfish-reeled-in-by-california-fisherman.html).
Invasion History on the East Coast:
Blue Catfish (Ictalurus furcatus) on the East Coast, especially the Potomac River, where believed to be introduced as an accidental contaminant of stocks of Channel Catfish (I. punctatus) by the United States Fish Commission at the turn of the century (Smith 1907). However, preserved voucher specimens labelled as I. furcatus were actually I. punctatus (Burkhead et al. 1980), so these early reports are unverified. In the 1960-70s, state fisheries agencies began stocking Blue Catfish to attract trophy fishermen with giant fish. The first planting was in 1964 to Lake Marion, South Carolina, which is in the Santee-Cooper river system. Subsequent state first introductions were: Georgia (1971, Savannah River), North Carolina (1975, Cape Fear and Neuse Rivers), and Virginia (1974-1977, Rappahannock and James Rivers) (Dahlberg and Scott 1979; Jenkins and Burkhead 1993; USGS Nonindigenous Aquatic Species Program 2018). In each state, Blue Catfish rapidly dispersed up and down rivers, and was officially and informally introduced to other tributaries. In some cases, such as the Satilla River, Georgia (Bonivecchio et al. 2012) and the Northwest River, a Back Bay tributary (Tolliver 2016). Blue Catfish are believed to have migrated through brackish water in the Intracoastal Waterway.
Blue Catfish were stocked in Chesapeake Bay watershed starting in the 1980s. In 1987 they were caught at Haines Point, in the Potomac River. They were stocked in reservoirs in the Occoquan basin, a Potomac tributary in the 1980s, so this fish could have been dispersed from there, or could have migrated from the Rappahannock, during time of high river flow (Nammick and Fulton 1987). Sizes of record fishes in the James and Rappahannock estuaries were reported in fishing columns and increased through the 80s and 90s. Catfish were first stocked in the Mattaponi River in 1985, and now occur in the Pamunkey and York Rivers as well. Since 1990, abundance of Blue Catfish has fluctuated in Virginia rivers, but peak abundances have become successively larger (Greenlee and Lim 2011; Schloesser et al. 2011). By 2002 Blue Catfish were widespread and increasing in abundance in the tidal freshwater Potomac (Starnes 2002). From 2008-2010, populations of Blue Catfish have established in the fresh-oligohaline tidal regions of the Patuxent, Nanticoke, Sassafras, and Susquehanna Rivers (Maryland Department of Natural Resources 2010; Schloesser et al. 2011). On August 3, 2011, a specimen was caught at Conowingo Dam, at the head of Chesapeake Bay (USGS Nonindigenous Aquatic Species Program 2018). Blue Catfish range extensions presumably resulted from a mixture of releases by fishermen and natural dispersal. The brackish waters of Chesapeake Bay have been less of a barrier than biologists had expected, these fish have been caught at salinities as high as 15 PSU (Schloesser et al. 2011). They have apparently dispersed across the Bay, or have been introduced, to the Nanticoke River, on the Eastern shore. The first catch there was in Seaford, Delaware in 2010 (USGS Nonindigenous Aquatic Species Program 2018). Multiple record-sized fish have been caught there.
Blue Catfish have been caught in the Christiana River, a tributary of the Delaware estuary, but their establishment there is unknown (2013, Rob Aguilar, personal communication; Delaware Division of Fish and Wildlife 2017).
Blue Catfish (Ictalurus furcatus) are large predatory Bullhead Catfishes in the family Ictaluridae. Fish in this family have four pairs of barbels, no scales, an adipose fin, stout spines at the origins of the dorsal and pectoral fins, and abdominal pelvic fins. The tail fin of the Blue Catfish is deeply forked, with rounded lobes. The adipose fin has a short base, with its free end free at the back, and far from the caudal fin. The base of the anal fin is relatively long, and tapered rearward, with a straight edge and 30-35 rays. The pectoral spines are stout and strongly serrated. The dorsal fin is relatively short, with one spine and six soft rays. The head is broad and depressed. Adults can reach 1650 mm but are usually less than 600 mm. A 1000 mm fish can weigh 23 kg (50 lb.) Blue Catfish are blue-black above, and silver-blue. silver-gray, or white below. They lack the small black spots that usually occur on the Channel Catfish (I. punctatus). The chin barbels are pale, while the other barbels are dusky (Page and Burr 1991; Jenkins and Burkhead 1993; Murdy et al. 1997; Moyle 2002).
Potentially Misidentified Species
Ameiurus catus (White Catfish) is native to the Atlantic Slope, and has been introduced to the San Francisco estuary and the Columbia River. The tail is forked, the pectoral spine has saw-like teeth, and the chin barbels are white. It is smaller than Blue or Channel Catfish (950 mm) (Page and Burr 1991).
Ameiurus melas (Black Bullhead) is native to the Mississippi-Great Lakes basin and has been introduced to the San Francisco estuary and the Columbia River. The tail is squared-off, the pectoral spine lacks saw-like teeth, and the chin barbels are dark (Page and Burr 1991).
Ameiurus natalis (Yellow Bullhead) is native to the Atlantic Slope and Mississippi-Great Lakes basin and has been introduced to the San Francisco estuary and the Columbia River. The tail is squared-off, the pectoral spine has saw-like teeth, and the chin barbels are white or yellow (Page and Burr 1991).
Ameiurus nebulosus (Brown Bullhead) is native to the Atlantic Slope and Mississippi-Great Lakes basin and has been introduced to the San Francisco estuary and the Columbia River and Fraser Rivers. The tail is squared-off, the pectoral spine has saw-like teeth, and the chin barbels are dark. The body has dark brown mottling (Page and Burr 1991).
Ictalurus punctatus (Channel Catfish) are native to the Mississippi-Gulf Basin, and the southeastern Coastal Plain, and has been introduced to the San Francisco estuary and the Columbia River. Adults are large, gray in color, sometimes with scattered dark spots. The caudal fin is deeply forked, and the anal fin has a curved edge (Page and Burr 1991).
Blue Catfish (Ictalurus furcatus) are large predatory freshwater catfish that do enter brackish water. The two sexes are not morphologically distinguishable. They mature at about 400-600 mm, at an age of about 4 years (Carlander 1969; Jenkins and Burkhead 1993). Spawning occurs at 21-24 C. Both sexes prepare a nest in sand or gravel and guard it. Fecundity is roughly estimated at 4,000-18, 000 eggs. Eggs and young are guarded by both sexes. They can be long-lived, a 41 kg specimen was 21 years old (Jenkins and Burkhead 1993). In Virginia tributaries of Chesapeake Bay, growth rate has decreased from 1998-2000 to 2014-2017, probably reflecting more intraspecific comptition (Nepal edt al. 2020).
Blue Catfish range from cold-temperate to subtropical climates. Adults have been collected at 15 PSU in the field (Schloesser et al. 2011). Their habitats include: pools, and sluggish runs over soft substrates in creeks and small to large rivers, impoundments, oxbows, and ponds (Page and Burr 1991). They are omnivorous, but because of their large size, they function as apex predators. In surveys of fish from Chesapeake tributaries, researchers reported their diet to include a lot detritus and plant matter. Fish <300 mm tend to consume more invertebrates, while large fish consume more fishes. Prey composition varied among tributaries and with season, indicating considerable opportunism (Groves and Love 2010; Schloesser et al. 2011); Schmitt et al. 2019). A DNA study of catfish gut contents indicates that Blue Catfish eat a greater quantity and variety of fishes then Channel Catfish (I. punctatus) or White Catfish (Ameiurus catus). Common prey are Menhaden (Brevoortia tyrannus), American Shad (Alosa sapidissima), River Herring (A. pseudoharengus, A. aestivalis), Gizzard Shad (Dorosoma cepedianum), White Perch (Morone americana), and Channel Catfish (Aguilar et al. 2017). Stable isotope studies show that during the spring migration of river herring and shad, the isotopic composition shifted from a freshwater to a marine profile, as a result of feeding on fish newly arrived from the sea (MacAvoy et al. 2000). Overall, Blue Catfish are omnivores, with one of the broadest feeding spectra known (Schmitt et al. 2019).
Fishes, invertebrates, aquaitc vegetation
fishes, birds, humans
|General Habitat||Nontidal Freshwater||None|
|General Habitat||Fresh (nontidal) Marsh||None|
|General Habitat||Grass Bed||None|
|General Habitat||Coarse Woody Debris||None|
|General Habitat||Tidal Fresh Marsh||None|
|General Habitat||Unstructured Bottom||None|
|Salinity Range||Limnetic||0-0.5 PSU|
|Salinity Range||Oligohaline||0.5-5 PSU|
|Salinity Range||Mesohaline||5-18 PSU|
Tolerances and Life History Parameters
|Minimum Temperature (ºC)||30.5||Field, James River, Virginia (Fabrzio et al. 2010)|
|Maximum Temperature (ºC)||None||None|
|Minimum Salinity (‰)||0||This is a freshwater fish.|
|Maximum Salinity (‰)||9||15 PSU, Field, Schloesser et al. 2011. 14 PSU, experimental (Allen and Avault 1971). In careful experiments at 22 C, there was no mortality at 13 PSU and 40-70 h survival at 17 PSU. The calculated LC 50 was 15.2-15.7 PSU for 72 hours. Salinity tolerance was greater for larger fish (Nepal and Fabrizio 2019). There is a field record at 22 PSU from the James River (Tuckey et al. 2017; Nepal and Fabrizio 2019). Howver, 9 Psu may be the maximum fro long-term survival and growth Inepal and Fabrizio 2020).|
|Minimum Reproductive Temperature||21||Carlander 1969|
|Minimum Reproductive Salinity||0||This is a freshwater fish.|
|Maximum Reproductive Salinity||2||Perry 1973|
|Minimum Length (mm)||400||Carlander 1969|
|Maximum Length (mm)||1,650||Page and Burr 1991|
|Broad Temperature Range||None||Cold Temperate-to-Subtropical|
|Broad Salinity Range||None||Limnetic-Mesohaline|
General ImpactsBlue Catfish (Ictalurus furcatus) have been introduced to many East Coast tributaries, and in the San Francisco Bay watershed. However, detailed studies of their predatory impacts and resulting implications for fisheries and conservation are largely focused on Chesapeake Bay. Blue Catfish can be giant, sometimes exceeding 23 kg (50 lbs), which makes them a major attraction for fishers. In the 1960s and 70s fisheries agencies use their large size to justify official introductions and unofficial transfers. In more recent decades, agencies are more concerned about biodiversity and conservation of native fisheries stocks, especially migratory species (MacAvoy et al. 2010; Groves and Love 2010). In Chesapeake Bay, commercial fishing of Blue Catfish is being promoted and the fish is often mentioned in restaurant advertisements (NOAA Chesapeake Bay Office 2018).
Blue X Channel Catfish hybrids are extensively used catfish aquaculture. In 2009, 13% of catfish hatched in US aquaculture operations were hybrids (APHIS Veterinary Services 2011).
|M130||Chesapeake Bay||Economic Impact||Fisheries|
|Blue Catfish (Ictalurus furcatus) are popular sportfish and commercial species, and one of the Chesapeake's largest fishes (Jenkins and Burkhead 1993; Murdy et al. 1997). In the spring and summer of 1995, and 1996, catches of large fish in the James and Rappahannock were frequently mentioned in the Washington Post. As populations increased in the Potomac, record fish captured attention among local fishermen and there was uncertainty in the Maryland Department of Natural Resources as to whether recognizing record catch would encourage illegal introductions of this invasive fish (Thomsen 2010). As a new top predator, they may be reducing abundance of other fishes, particularly shads, migratory herrings (Alosa spp.), and menhaden (MacAvoy et al. 2000; Schloesser et al. 2011). Potentially, Blue Catfish and the other introduced giant catfish, Pylodictis olivaris (Flathead Catfish), may be interfering with attempts to restore American Shad (Alosa sapidissima) (Garman et al. 2010; Groves and Love 2010). Management of Blue Catfish is complicated by need to balance the recreational fishery with the need to protect native fish stocks. Some Chesapeake watermen have switched from Blue Crabs to Blue Catfish, and this invasive fish is advertised by local restaurants (NOAA Chesapeake Bay Office 2018). However, large Blue Catfish have high levels of chemical contamination making them unsafe to eat (Schloesser et al. 2011).Fish ish under 760 mm (30 in.) are considered safe to eat.|
|M130||Chesapeake Bay||Ecological Impact||Predation|
|Predation- Blue Catfish (Ictalurus furcatus) are likely to be important predators, given their size and piscivorous food habits (Carlander 1969; Jenkins and Burkhead 1993). Statistical analyses indicate that Blue Catfish have adversely affected clupeid (herring- family fishes) populations in the James and Rappahannock Rivers (Austin 1998, personal communication). Gut and isotope analyses indicate that anadromous Alosa spp. (Shad, Alewives, Blueback Herring) form a substantial fraction of the Blue Catfish’s diet, resulting in a strong marine signature in the isotope composition of the freshwater predator (MacAvoy et al. 2000). Feeding studies indicate that younger fish in the James, York, and Rappahannock Rivers (smaller than 300 mm) feed mostly on benthic invertebrates, but that larger fishes (300-600mm) feed mostly on fishes. Menhaden (Brevoortia tyrannus) was the most frequent prey species (Schloesser et al. 2011). DNA studies show that Blue Catfish feed on at least 20 species of fishes (Aguilar et al. 2017).|
|S050||Cape Fear River||Ecological Impact||Predation|
Ictalurus furcatus (Blue Catfish) are a major predator on fishes and invertebrates in the Cape Fear River, The largest size class of individuals (<600 mm) had 31% fishes and 42% invertebrates (by weight) in their sotmachs. invertebrates, Asian Clams (Corbicula fluminea) decreased in frequency with fish size ,from 86% (by weight) for fish below 100 mm, to 33% for fish over 300 mm (Belkoski et al. 2021)
|S050||Cape Fear River||Economic Impact||Fisheries|
Blue Catfish are a major game fish in the Cape Fear River (Belkoski et al. 2021).
Regional Distribution Map
|Bioregion||Region Name||Year||Invasion Status||Population Status|
|P090||San Francisco Bay||1979||Def||Estab|
|G170||West Mississippi Sound||0||Native||Estab|
|G330||Lower Laguna Madre||0||Native||Estab|
|G290||San Antonio Bay||0||Native||Estab|
|G310||Corpus Christi Bay||0||Native||Estab|
|G125||_CDA_G125 (Pensacola Bay)||1996||Def||Estab|
|S050||Cape Fear River||1979||Def||Estab|
|S160||St. Andrew/St. Simons Sounds||2011||Def||Estab|
|G320||Upper Laguna Madre||0||Native||Estab|
|G160||East Mississippi Sound||0||Native||Estab|
|S166||_CDA_S166 (Cumberland-St. Simmons)||2011||Def||Estab|
ReferencesAllen, Kenneth O.; Avault, James W. (1971) Notes on the relative salinity tolerance of channel and blue catfish, Progressive Fish-Culturist 33(3): 135-137
Bean, Barton A.; Weed, Alfred C. (1911) Recent additions to the fish fauna of the District of Columbia, Proceedings of the Biological Society of Washington 24: 171-174
Belkoski, David J.; Drzewicki, Maya; Scharf, Frederick S. (2021) Specialized feeding patterns and marine resource use by nonnative catfishes in a coastal river ecosystem revealed by dietary and stable isotopic analyse, Marine and Coastal Fisheries: Dynamics, Management, and Ecosystem Science 13: 564–582
Bonvechio, Timothy F.; Bowen, Bryant R.; Mitchell, Jason S.; Bythwood, Justin (2012) Non-indigenous range expansion of the Blue Catfish (Ictalurus furcatus) in the Satilla River, Georgia, Southeastern Naturalist 11(2): 355-358
Burkhead, Noel M.; Jenkins, Robert E.; Maurakis, Eugene G. (1980) New records, distribution, and diagnostic characters of Virginia ictalurid catfishes with an adnexed adipose fin, Brimleyana 4: 75-91
Carlander, Kenneth D. (1969) Handbook of freshwater fishery biology. Vol. 1., In: (Eds.) . , Ames. Pp. <missing location>
Cohen, Andrew N.; Carlton, James T. (1995) Nonindigenous aquatic species in a United States estuary: a case study of the biological invasions of the San Francisco Bay and Delta, U.S. Fish and Wildlife Service and National Sea Grant College Program (Connecticut Sea Grant), Washington DC, Silver Spring MD.. Pp. <missing location>
Dahlberg, Michael D., Scott, Donald C. (1971) Introductions of freshwater fishes in Georgia, Bulletin of the Georgia Academy of Science 29(245-252): <missing location>
Dill, William A.; Cordone, Almo J. (1997) History and status of introduced fishes in California, 1871-1996, California Department of Fish and Game Fish Bulletin 178: 1-414
Fuller, Pam. L.; Nico, Leo; Williams, J. D. (1999) Nonindigenous fishes introduced into inland waters of the United States, American Fisheries Society, Bethesda MD. Pp. <missing location>
2010 Status of Flathead Catfish in Chesapeake Bay rivers. PowerPoint presentation, archive.chesapeakebay.net/.../49012_12-01-10_Presentation_4_11059.pdf
Greenlee, Bob (2011) <missing title>, Virginia Department of Game and Inland Fisheries Virginia Department of Game and Inland Fisheries, Richmond VA. Pp. 1-6
Greenlee, Robert S.; Lim, Catherine M. (2011) Searching for equilibrium: Population parameters and variable recruitment in introduced blue catfish populations in four Virginia tidal river systems, American Fisheries Society Symposium 77: 349-367
2010 Tidal Blue Catfish in Maryland waters. Powerpoint Presentation archive.chesapeakebay.net/.../49012_120110_Presentation_5_11059.pdf
2012 Texas Freshwater Fishes. http://www.bio.txstate.edu/~tbonner/txfishes/
Jenkins, Robert E.; Burkhead, Noel M. (1993) Freshwater Fishes of Virginia, American Fisheries Society, Bethesda, MD. Pp. <missing location>
Lee, David S.; Gilbert, Carter R.; Hocutt, Charles H.; Jenkins, Robert E.; McAllister, Don E.; Stauffer, Jay R. (1980) Atlas of North American freshwater fishes, North Carolina State Museum of Natural History, Raleigh. Pp. <missing location>
Liuzzo, M.; Alfonso, G.; Beli, E.; Arculeo, M.; Marrone, F. (2018) First record of the alien leech Myzobdella lugubris Leidy, 1851 (Hirudinea, Piscicolidae) in the Palearctic, Limnetica 37(2): 311-318
Lopez-Soriano, Joaquín López; Salgado, Sergio Quiñonero (2019) [First record of Leiosolenus aristatus (Bivalvia: Mytilidae) on the CatalanCoast, Spira 7: 93-95
MacAvoy, S. E.; Macko, S. A.; McIninch, S. P. (2000) Marine nutrient contributions to freshwater apex predators., Oecologia 122: 568-573
Mathis, Wayne N. (1995) Shore files of the Galapagos Islands, Annals of the Entomological Society of America 66(5): 627-640
Maurakis, Eugene; Woolcott, William S.; Jenkins, Robert E. (1987) Physiographic analyses of the longitudinal distribution of fishes in the Rappahannock River, Virginia, ASB Bulletin 34(1): 1-14
Menhinick, Edward F. (1991) The Freshwater Fishes of North Carolina, North Carolina Wildlife Resources Commission, Raleigh. Pp. 45-203
Menhinick, Edward F., Burton, Thomas M., Bailey, Joseph R. (1974) An annotated checklist of the freshwater fishes of North Carolina, Journal of the Elisha Mitchell Scientific Society 89: 24-50
Murdy, Edward O.; Birdsong, Ray S.; Musick, John A. (1997) Fishes of Chesapeake Bay, Smithsonian Institution Press, Washington, D.C.. Pp. 57-289
Nammick, Marta F.; Fulton, Jean M. (1987) A blue catfish, Ictalurus furcatus, from the Potomac River, The Maryland Naturalist 31(2): 58
Nepal, Vaskar; Fabrizio, Mary C. (2019) High salinity tolerance of invasive blue catfish suggests potential for further range expansion in the Chesapeake Bay region, PLOS ONE 14(11): e0224770.
Nepal, Vaskar; Fabrizio, Mary C. (2020) Sublethal effects of salinity and temperature on non-native blue catfish: Implications for establishment in Atlantic slope drainages, PLOS ONE 15(12): e0244392
Nepal, Vaskar; Fabrizio, Mary C..; Connelly, William J. (2020) Phenotypic plasticity in life-history characteristics invasive blue catfish, Ictalurus furcatus, Fisheries Research 230(105650): Published online
Orth, Donald J.; Schmitt, Joseph D.; Hilling, Corbin D. (2020) Hyperbole, simile, metaphor, and invasivore: Messaging about non-native Blue Catfish expansion, Fisheries 45(12): 639-647
Page, Lawrence M.; Burr, Brooks M. (1991) Freshwater Fishes: North America North of Mexico, Houghton-Mifflin, Boston. Pp. <missing location>
Perry, W. G. (1973) Notes on the spawning of blue and channel catfish in brackish water ponds, Progressive Fish-Culturist 35(3): 164-166
Raasch, Maynard S.; Altemus, Vaughn L., Sr. (1991) Delaware's freshwater and brackish water fishes, a popular account , Society of Natural History of Delaware, Wilmingotn, Delaware. Pp. <missing location>
Roberts, Fannon A., III (2-017) Tiny insect thought to be killing coastal cane might only be part of problem, scientists say, Baton Rouge Advocate <missing volume>: Published online
Rodhe, Fred C.; Arndt, Rudolf G.; Lindquist, David G.; Parnell, James F. (1994) <missing title>, University of North Carolina Press, Chapel Hill. Pp. <missing location>
Schloesser, Ryan W. and 6 authors (2011) Ecological role of Blue Catfish in Chesapeake Bay communities and implications for management, American Fisheries Society Symposium 77: 369-382
Schmitt, Joseph D.; Hilling, Corbin D.;Orth, Donald J. (2021) Estimates of food consumption rates for invasive Blue Catfish, Transactions of the American Fisheries Society Published online: <missing location>
Simon, Carol A.; van Niekerk, H. Helene; Burghardt, Ingo; ten Hove, Harry A.; Kupriyanova, Elena K. (2019) Not out of Africa: Spirobranchus kraussii (Baird, 1865) is not a global fouling and invasive serpulid of Indo-Pacific origin, Biological Invasions 14(3): 221–249.
Starnes, Wayne C. (2002) Current diversity, historical analysis, and biotic integrity of fishes in the lower Potomac basin in the vicinity of Plummers Island, MD, Proceedings of the Biological Society of Washington 115(2): 273-320
Starnes, Wayne C.; Odenkirk, John; Ashton, Matthew J. (2011) Update and analysis of fish occurrences in the lower Potomac River drainage in the vicinity of Plummers Island, Maryland—Contribution XXXI to the natural history of Plummers Island, Maryland, Proceedings of the Biological Society of Washington 124: 280-309
Thomson, Candus (8/15/2010) Blue catfish unvelcome in Md.- except in contests, Baltimore Sun <missing volume>: Sports-4
Thomson, Candus (9/27/2010) Blue cafish given a reprieve, Baltimore Sun <missing volume>: <missing location>
Tolliver, Lee (3/26/16) Norfolk man catches big Northwest River catfish, Virginian-Pilot Published online: <missing location>
2003-2022 Nonindigenous Aquatic Species Database. Gainesville, FL. http://nas.er.usgs.gov
Viverette, Catherine B. and 5 authors (2007) Finfish-waterbird trophic interactions in tidal freshwater tributaries of the Chesapeake Bay, Waterbirds 30(Special Publ. 1): 50-62
Wetzer, Regina; Wall, Adam; Bruce, Niel L. (2021) Redescription of Gnorimosphaeroma oregonense (Dana, 1853) (Crustacea, Isopoda, Sphaeromatidae), designation of neotype, and 16S-rDNA molecular phylogeny of the north-eastern Pacific species, ZooKeys 1037: 23-56
Yan, T.; Yan, W. X. ; Dong, Y.; Wang, H. J.; Yan, Y.;Liang, G. H. (2009) Marine fouling on floating installations west of Dongsha Islands, the northern South China Sea, International Biodeterioration & Biodegradation 63: 1079-103