Fishes

FISHES

of the Lower Susquehanna River Watershed

With (forthcoming) commentary on the species including notes from the historic writings of nineteenth-century geologist, naturalist, and philologist Professor Samuel Steman Haldeman, Linnaean Society of Lancaster City and County naturalist Jacob Stauffer, and ichthyologist Tarleton Hoffman Bean.


Samuel Steman Haldeman was born in 1812 at Locust Grove along the Susquehanna River just downstream of Conewago Falls near Bainbridge, Lancaster County, Pennsylvania.  In 1842 and 1844, he was the first to describe the Chesapeake Logperch (Percina bimaculata), a fish which was long considered to be synonymous with the widespread Common Logperch (Percina caprodes) until recent mitochondrial DNA analysis proved it to be a valid species unique to the lower Susquehanna and other tributaries of the upper Chesapeake Bay.  (Mathew Brady image-Library of Congress)
Tarleton Hoffman Bean (back row left) with co-members of the Smithsonian Institution staff, circa 1878.  Bean was born in Bainbridge, Lancaster County, Pennsylvania, in 1846 and spent his youth along the Susquehanna River there.  He studied botany at the nearby Millersport State Normal School, present-day Millersville University.  (Smithsonian National Museum of Natural History image www.si.edu)

SPECIES STATUS KEY

extinct-a native species no longer existing or living.

extirpated-a native species no longer occurring in the wild in the Lower Susquehanna River Watershed.

exotic-a free-ranging escaped or released non-native species or variety; most are unwanted pets, domesticated farm animals, or zoo specimens.

introduced-a non-native species released into the waters of the Susquehanna watershed, including fishes stocked to create temporary populations as well as those that establish self-sustaining breeding populations—often at the expense of one or more native species.  Introduced fishes include “native transplants”, species native to North American waters, but not indigenous to the Susquehanna and its tributaries.

Federally Endangered-a native species listed by the United States government as imminently in danger of extinction.

PA Endangered-a native species listed by the Commonwealth of Pennsylvania as imminently in danger of extinction or of extirpation as a breeding species in the state.

MD Endangered-a native species listed by the State of Maryland as imminently in danger of extinction or of extirpation as a breeding species in the state.

Federally Threatened-a native species listed by the United States government as under threat to become an endangered species in the foreseeable future.

PA Threatened-a native species listed by the Commonwealth of Pennsylvania as under threat to become an endangered species in the state in the foreseeable future.

MD Threatened-a native species listed by the State of Maryland as under threat to become an endangered species in the state in the foreseeable future.

PA Candidate-an uncommon native species that could, in the future, become listed by the Commonwealth of Pennsylvania as endangered or threatened in the state.


A LIST OF THE FISHES

of the Lower Susquehanna River Watershed

Classified using traditional taxonomic ranks and selected cladistic groups.

 Domain-Eukaryota

Kingdom-Animalia

Phylum-Chordata


Class-Hyperoartia?:

The lampreys, a group with disputed relationships to other chordates, are, in accordance with traditional listings of fishes, placed here.

Order-Petromyzontiformes

Family-Petromyzontidae

Lampetra aepyptera (Least Brook Lamprey)-PA Candidate

Petromyzon marinus (Sea Lamprey)

Least Brook Lamprey (Lampetra aepyptera).  (United States Fish and Wildlife Service image of specimen in NCTC Freshwater Fisheries Teaching Collection)
Sea Lamprey (Petromyzon marinus).  (NOAA Fisheries image by Paul Music)
Sea Lamprey (Petromyzon marinus).  (NOAA Fisheries image by Paul Music)

Subphylum-Vertebrata

Superclass-Osteichthyes/Clade-Euteleostomi:

The “bony vertebrates” including the Actinopterygians, the ray-finned fishes, and the Sarcopterygians, the lobe-finned fishes and tetrapods.  All members of the clade Sarcopterygii presently occurring in the Susquehanna watershed (amphibians, reptiles, birds, and mammals including humans) are tetrapod descendants of extinct lobe-finned fishes.

Class/Clade-Actinopterygii:

The ray-finned fishes.

Order-Acipenseriformes

Family-Acipenseridae

Acipenser brevirostrum (Shortnose Sturgeon)-Federally Endangered/PA Endangered/MD Endangered

Acipenser oxyrhynchus (Atlantic Sturgeon)-extirpated-Federally Endangered/PA Endangered/MD Endangered

Shortnose Sturgeon (Acipenser brevirostrum).  (NOAA image)
Atlantic Sturgeon (Acipenser oxyrhynchus).  (NOAA image)

Order-Lepisosteriformes

Family-Lepisosteridae

Lepisosteus osseus (Longnose Gar)-extirpated

Longnose Gar (Lepisosteus osseus).  (United States Fish and Wildlife Service image by Ryan Hagerty)

Order-Amiiformes

Family-Amiidae

Amia calva (Bowfin)-introduced

Bowfin (Amia calva) are indigenous to the Great Lakes, the Mississippi and Ohio Rivers, and the Atlantic and Gulf Coastal Plains south of Virginia.  They were introduced into the lower Susquehanna River as native transplants in the years prior to 1972’s Hurricane Agnes.  Few were seen after the polluted floodwaters receded.  (United States Fish and Wildlife Service image by Ryan Hagerty)

Order-Anguilliformes

Family-Anguillidae

Anguilla rostrata (American Eel)

American Eel (Anguilla rostrata).  (Vintage 35 mm image)
American Eel (Anguilla rostrata).

Order-Clupeiformes

Family-Clupeidae

Alosa aestivalis (Blueback Herring)

Alosa mediocris (Hickory Shad)-PA Endangered

Alosa pseudoharengus (Alewife)-introduced

Alosa sapidissima (American Shad)

Dorosoma cepedianum (Gizzard Shad)

A Blueback Herring (Alosa aestivalison) on the top and, for comparison, an Alewife (Alosa pseudoharengus) on the bottom.  (NOAA Fisheries image)
Hickory Shad (Alosa mediocris).
Alewife (Alosa pseudoharengus) during migration.  (NOAA Fisheries image by Jerry Prezioso)
A catch-and-release angler returning an American Shad to the Susquehanna River.  (Vintage 35 mm image)
An American Shad (Alosa sapidissima) on the top and, for comparison, an Alewife (Alosa pseudoharengus) on the bottom.  (NOAA Fisheries image by Jim Hawkes)
Fishes of the Lower Susquehanna River Watershed: Gizzard Shad using fish passage
Gizzard Shad swimming by the counter’s window at the York Haven Dam Fish Passage just upstream from Conewago Falls.
Schooling juvenile Gizzard Shad (Dorosoma cepedianum).  (Vintage 35 mm image)

Order-Cypriniformes

Family-Cyprinidae

Campostoma anomalum (Central Stoneroller)

Carassius auratus (Goldfish)-introduced

Clinostomus elongatus (Redside Dace)-upper Susquehanna species

Clinostomus funduloides (Rosyside Dace)

Ctenopharyngodon idella (Grass Carp)-introduced

Cyprinella analostanus (Satinfin Shiner)

Cyprinella spiloptera (Spotfin Shiner)

Cyprinus carpio (Common Carp)-introduced

Cyprinus rubrofuscus (Amur Carp—including ornamental Koi)-exotic

Exoglossum maxillingua (Cutlip Minnow)

Hybognathus regius (Eastern Silvery Minnow)

Luxilus cornutus (Common Shiner)

Margariscus margarita (Pearl Dace)-MD Threatened

Nocomis micropogon (River Chub)

Notemigonus crysoleucas (Golden Shiner)

Notropis amoenus (Comely Shiner)

Notropis atherinoides (Emerald Shiner)-exotic

Notropis bifrenatus (Bridle Shiner)-upper Susquehanna species-PA Endangered

Notropis buccatus (Silverjaw Minnow)

Notropis hudsonius (Spottail Shiner)

Notropis procne (Swallowtail Shiner)

Notropis rubellus (Rosyface Shiner)

Notropis volucellus (Mimic Shiner)-introduced

Phoxinus eos (Northern Redbelly Dace)-extirpated-upper Susquehanna species-PA Endangered

Pimephales notatus (Bluntnose Minnow)

Pimephales promelas (Fathead Minnow)-introduced

Rhinichthys atratulus (Eastern Blacknose Dace)

Rhinichthys cataractae (Longnose Dace)

Semotilus atromaculatus (Creek Chub)

Semotilus corporalis (Fallfish)

Tinca tinca (Tench)-introduced

Large Minnows

 

Large Shiners

 

Minnows

(with a splint-like first ray in the dorsal fin)

 

Shiners

 

Bottom-dwelling Minnows

Central Stoneroller (Campostoma anomalum).
Goldfish (Carassius auratus).
Rosyside Dace (Clinostomus funduloides).  (United States Fish and Wildlife Service image by Ryan Hagerty)
Grass Carp (Ctenopharyngodon idella).  (United States Fish and Wildlife Service image by Ryan Hagerty)
Within the Lower Susquehanna River Watershed, there are two shiners in the genus Cyprinella: the Satinfin Shiner (C. analostanus) and the Spotfin Shiner (C. spiloptera).  These very similar species are generally regarded as inseparable in the field.  Male Cyprinella shiners in breeding condition (center) are known for their white-edged fins and vibrantly colored iridescent scales.  (Vintage 35 mm image)
A possible breeding male Satinfin Shiner (Cyprinella analostanus).  Traditional field marks of the Satinfin Shiner include dark pigment in all margins between the rays of the dorsal fin and a total of nine rays in the anal fin.  (Vintage 35 mm image)
A possible breeding male Spotfin Shiner (Cyprinella spiloptera).  Traditional field marks of the Spotfin Shiner include dark pigment in the margins between the rays at the anterior end of the dorsal fin and a total of eight rays in the anal fin.
Common Carp (Cyprinus carpio).
Cutlip Minnow (Exoglossum maxillingua).
Common Shiner (Luxilus cornutus).
A juvenile Golden Shiner (Notemigonus crysoleucas).
Comely Shiner (Notropis amoenus).  (Vintage 35 mm image)
Emerald Shiner (Notropis atherinoides).  (National Park Service image)
Swallowtail Shiner (Notropis procne).
Rosyface Shiner (Notropis rubellus).  (Vintage 35 mm image)
Mimic Shiner (Notropis volucellus).  (United States Fish and Wildlife Service image)
Fathead Minnow (Pimephales promelas).
A breeding condition male Bluntnose Minnow (Pimephales notatus).
Blacknose Dace (Rhinichthys atratulus).
Longnose Dace (Rhinichthys cataractae).

Family-Catostomidae

Carpiodes cyprinus (Quillback)

Catostomus commersoni (White Sucker)

Erimyzon oblongus (Creek Chubsucker)

Hypentelium nigricans (Northern Hogsucker)

Moxostoma anisurum (Silver Redhorse)-?

Moxostoma macrolepidotum (Shorthead Redhorse)

Quillback (Carpiodes cyprinus). (United States Fish and Wildlife Service image by Brett Billings)
White Sucker (Catostomus commersoni).  (United States Fish and Wildlife Service image by Brett Billings)
Creek Chubsucker (Erimyzon oblongus).  (Vintage 35 mm image)
Northern Hog Sucker (Hypentelium nigricans).  (Vintage 35 mm image)
Shorthead Redhorse (Moxostoma macrolepidotum).

Order-Siluriformes

Family-Ictaluridae

Ameirus catus (White Catfish)

Ameirus natalis (Yellow Bullhead)

Ameirus nebulosus (Brown Bullhead)-includes Gronias nigrilabris (“Conestoga Blind Catfish”)

Ictalurus furcatus (Blue Catfish)-introduced

Ictalurus punctatus (Channel Catfish)-introduced

Noturus gyrinus (Tadpole Madtom)-PA Endangered

Noturus insignis (Margined Madtom)

Pylodictis olivaris (Flathead Catfish)-introduced

An adult Yellow Bullhead (Ameirus natalis).
A pair of juvenile Yellow Bullheads (Ameirus natalis).  (Vintage 35mm image)
Blue Catfish (Ictalurus furcatus).  (United States Fish and Wildlife Service image by Brett Billings)
Channel Catfish (Ictalurus punctatus).  (United States Fish and Wildlife Service image by Brett Billings)
Fishes of the Lower Susquehanna River Watershed: juvenile Channel Catfish
A juvenile Channel Catfish (Ictalurus punctatus).
Tadpole Madtom (Noturus gyrinus).  (United States Geological Survey image)
Margined Madtom (Noturus insignis).
A juvenile Flathead Catfish (Pylodictis olivaris) among the Pothole Rocks at Conewago Falls.

Order-Characiformes

Family-Sarasalmidae

Colossoma or Piaractus species (Pacu species)-exotic

Piaractus brachypomus (Red-bellied Pacu)-exotic

Pygocentrus nattereri (Red-bellied Piranha)-exotic

As juveniles, these Red-bellied Pacu (Piaractus brachypomus) could be mistaken for Red-bellied Piranha (Pygocentrus nattereri).  Both are tropical natives of South America’s Amazon River system.  The former is sometimes sold in the aquarium and food trade using the name of the latter.  Pacu are often called vegetarian piranhas.  They possess teeth resembling human molars while piranhas have sharp-pointed teeth.  As they age, Red-bellied Pacu soon lose their red color and attain lengths of two feet or more, quickly outgrowing most home aquaria.  When no longer wanted as pets, pacu are oft times released into the ponds, lakes, and streams of the lower Susquehanna watershed.  In 2009, an angler caught a Red-bellied Pacu while fishing in the Conestoga River in Manheim Township, Lancaster County, Pennsylvania.  They’ve been found in Lake Placida on the campus of Elizabethtown College, also in Lancaster County.  In autumn, pacu released into the waters of the Susquehanna basin are killed by falling temperatures.  (United States Geological Survey image)

Order-Esociformes

Family-Esocidae

Esox americanus (Redfin Pickerel)-introduced

Esox niger (Chain Pickerel)

Esox reicherti (Amur Pike)-introduced

Esox lucius (Northern Pike)-introduced

Esox lucius x Esox reicherti (“Hybrid Pike”)-introduced-upper west branch species-186 fish stocked in Glendale Lake northwest of Altoona—last documented in 1976

Esox masquinongy (Muskellunge)-introduced

Esox lucius x Esox masquinongy (“Tiger Muskellunge”)-introduced

Northern Pike (Esox lucius).  (National Park Service image)
Muskellunge (Esox masquinongy).  (United States Fish and Wildlife Service image by Eric Engbretson)
The “Tiger Muskellunge” (Esox lucius x Esox masquinongy) is the sterile cross of a male Northern Pike and a female Muskellunge.  These hybrids grow more vigorously under captive rearing conditions than their pure-bred parents.  (United States Fish and Wildlife Service NCTC Freshwater Fishes Teaching Collection image by Matthew Patterson)

Order-Osmeriformes

Family-Osmeridae

Osmerus mordax (Rainbow Smelt)-introduced-upper Susquehanna/upper Juniata species

Rainbow Smelt (Osmerus mordax) were stocked as a forage and angling species in Harvey’s Lake in Lackawanna County (circa 1952) and Raystown Lake in Huntingdon County (pre-1988).  (NOAA Fisheries image by Katrina Mueller)

Order-Salmoniformes

Family-Salmonidae

Oncorhynchus kisutch (Coho Salmon)-introduced-upper Susquehanna species

Oncorhynchus mykiss (Rainbow Trout)-introduced

Oncorhynchus nerka (Sockeye Salmon)-introduced-upper Susquehanna species

Oncorhynchus tshawytscha (Chinook Salmon)-introduced-upper Susquehanna species

Salmo salar (Atlantic Salmon)-introduced

Salmo trutta (Brown Trout)-introduced

Salvelinus fontinalis (Brook Trout)

Salvelinus namaycush (Lake Trout)-introduced-upper Susquehanna species

Salvelinus namaycush x Salvelinus fontinalis (Splake hybrid)-introduced

Coho Salmon (Oncorhynchus kisutch) were stocked (circa 1967) in Harvey’s Lake in Lackawanna County, PA.  (United States Department of the Interior Bureau of Land Management image)
Rainbow Trout (Oncorhynchus mykiss).  (United States Fish and Wildlife Service image by Ryan Hagerty)
Sockeye Salmon (Oncorhynchus nerka) were stocked in Lake Winola west of Scranton (circa 1923), then in Harvey’s Lake near Wilkes-Barre in Lackawanna County, PA (circa 1967).  (United States Fish and Wildlife Service image)
Introductions of Chinook Salmon (Oncorhynchus tshawytscha) in the upper Susquehanna watershed near Scranton failed during the late nineteenth century and again circa 1940.  (United States Fish and Wildlife Service image)
Atlantic Salmon (Salmo salar) were stocked (circa 1975) in Laurel Lake (Reservoir) in the Juniata River watershed in Mifflin County, PA.  (NOAA Fisheries image by Betty Holmes)
Brown Trout (Salmo trutta).  (United States Fish and Wildlife Service image by Robert Pos)
Brook Trout (Salvelinus fontinalis).  (United States Fish and Wildlife Service image)
Lake Trout (Salvelinus namaycush) have been stocked repeatedly in Harvey’s Lake in Lackawanna County, PA.  (United States Geological Survey image)
The Splake (Salvelinus namaycush x Salvelinus fontinalis) is a hybrid created in a fish hatchery by crossing a female Lake Trout and a male Brook Trout.  To the disappointment of avid anglers, a “trophy-size” Brook Trout can instead turn out to be a Splake.  These hybrids have been observed as they transit the fish lifts at the hydroelectric dams on the lower Susquehanna.  (United States Fish and Wildlife Service image by Lindsey Adams)

Order-Beloniformes

Family-Belonidae

Strongylura marina (Atlantic Needlefish)

Tylosurus acus (Agujon)

Atlantic Needlefish (Strongylura marina) wander from the brackish waters of Chesapeake Bay into the fresh waters of its tributaries.  They were probably a regular visitor to the lower Susquehanna prior to the construction of man-made dams.  Since their installation during the late twentieth century, Atlantic Needlefish have occasionally been recorded using the fish lifts at the hydroelectric dams to ascend the river.  (NOAA Southeast Fisheries Science Center image from the collection of Brandi Noble)

Order-Cyprinodontiformes

Family-Cyprinodontidae

Fundulus diaphanus (Banded Killifish)

Fundulus heteroclitus (Mummichog)

Banded Killifish (Fundulus diaphanus).  (Vintage 35 mm image)
Mummichogs (Fundulus heteroclitus).  (Vintage 35 mm image)

Family-Poeciliidae

Gambusia holbrooki (Eastern Mosquitofish)-introduced

Order-Gasterosteiformes

Family-Gasterosteidae

Apeltes quadracus (Fourspine Stickleback)

Culaea inconstans (Brook Stickleback)introduced-upper Juniata-PA Candidate

Order-Scorpaeniformes

Family-Cottidae

Cottus bairdi (Mottled Sculpin)

Cottus caeruleomentum (Blue Ridge Sculpin)

Cottus cognatus (Slimy Sculpin)

Cottus girardi (Potomac Sculpin)

Slimy Sculpin (Cottus cognatus).  (United States Fish and Wildlife Service image by Ryan Hagerty)
Potomac Sculpin (Cottus girardi).  (United States Fish and Wildlife Service image by Ryan Hagerty)

Order-Perciformes

Family-Percichthydae

Morone americana (White Perch)

Morone chrysops (White Bass)-introduced

Morone saxatilis (Striped Bass)

Morone saxatilis x Morone chrysops  (“Hybrid Striped Bass”)-introduced

White Bass (Morone chrysops).  (United States Fish and Wildlife Service image)
Striped Bass (Morone saxatilis).  (United States Fish and Wildlife Service image by Ryan Hagerty)
A “Hybrid Striped Bass” (Morone saxatilis x Morone chrysops) is a hatchery-produced cross of a male Striped Bass and a female White Bass, or of a female Striped Bass and a male White Bass.  The former is sometimes called a “Sunshine Bass”, the latter a “Palmetto Bass”.  These hybrids are able to withstand higher water temperatures and lower dissolved oxygen levels than pure-bred Stripers, hence they are better suited for aquaculture and nursery rearing.  Because female Striped Bass produce far more eggs than can female White Bass, the cross yielding the “Palmetto Bass” is favored by hatchery operators.  In the lower Susquehanna valley, “Hybrid Striped Bass” are raised commercially at a fish farm just downriver from Conewago Falls on Brunner Island in York County.  (United States Fish and Wildlife Service image by Ryan Hagerty)

Family-Centrarchidae

Ambloplites rupestris (Rock Bass)-introduced

Enneacanthus gloriosus (Bluespotted Sunfish)

Lepomis auritus (Redbreast Sunfish)

Lepomis cyanellus (Green Sunfish)-introduced

Lepomis gibbosus (Pumpkinseed)

Lepomis macrochirus (Bluegill)-introduced

Lepomis microlophus (Redear Sunfish)-introduced

Micropterus dolomieu (Smallmouth Bass)-introduced

Micropterus salmoides (Largemouth Bass)-introduced

Pomoxis annularis (White Crappie)-introduced

Pomoxis nigromaculatus (Black Crappie)-introduced

Rock Bass (Ambloplites rupestris).  (United States Fish and Wildlife Service image)
Redbreast Sunfish (Lepomis auritus).  (United States Fish and Wildlife Service image by Ryan Hagerty)
A juvenile Redbreast Sunfish (Lepomis auritus).  (United States Fish and Wildlife Service image by Ryan Hagerty)
Bluegill (Lepomis macrochirus).  (United States Fish and Wildlife Service image by Ryan Hagerty)
“Hybrid Sunfish” (Lepomis macrochirus x Lepomis cyanellus) are produced in fish hatcheries by crossing a male Bluegill with a female Green Sunfish.  The offspring, of which ninety percent or more are male, grow quickly to an attractive size for anglers.  Other Lepomis hybrids are possible in the wild, especially where non-native sunfish have been introduced among native species.  (United States Fish and Wildlife Service image by Sam Stukel)
A “Hybrid Sunfish” found occurring in Conewago Creek east of Conewago Falls, probably a Bluegill/Pumpkinseed (Lepomis macrochirus x Lepomis gibbosus) or Bluegill/Redbreast Sunfish (Lepomis macrochirus x Lepomis auritus) cross.  (Vintage 35 mm image)
Redear Sunfish (Lepomis microlophus).  (United States Fish and Wildlife Service image by Ryan Hagerty)
Smallmouth Bass (Micropterus dolomieu).  (Vintage 35 mm image)
Black Crappie (Pomoxis nigromaculatus).  (United States Fish and Wildlife Service image by Eric Engbretson)

Family-Percidae

Etheostoma blennioides (Greenside Darter)-introduced

Etheostoma flabellare (Fantail Darter)

Etheostoma olmstedi (Tessellated Darter)

Etheostoma sellare (Maryland Darter)-Federally Endangered/MD Endangered

Etheostoma zonale (Banded Darter)-introduced

Percina bimaculata (Chesapeake Logperch)-PA Threatened/MD Threatened

Percina peltata (Shield Darter)

Perca flavescens (Yellow Perch)

Sander vitreus (Walleye)-introduced

Fantail Darter (Etheostoma flabellare).  (United States Fish and Wildlife Service image by Ryan Hagerty)
Tessellated Darter (Etheostoma olmstedi).
Banded Darter (Etheostoma zonale).  (Vintage 35 mm image)
Banded Darter (Etheostoma zonale).  (Vintage 35 mm image)
Fishes of the Lower Susquehanna River Watershed: Banded Darter
Banded Darter (Etheostoma zonale).
A Banded Darter (Etheostoma zonale) on top and, for comparison, a Tessellated Darter (Etheostoma olmstedi) on the bottom.
Chesapeake Logperch (Percina bimaculata), a species first described by Samuel Steman Haldeman in 1842 and 1844.  Long considered to be synonymous with the widespread Common Logperch (Percina caprodes), recent mitochondrial DNA analysis proved it to be a valid species unique to the lower Susquehanna and other tributaries of the upper Chesapeake Bay.  (United States Fish and Wildlife Service Image by Kayt Jonsson)
Shield Darter (Percina peltata).  (United States Fish and Wildlife Service Image by Kayt Jonsson)
Yellow Perch (Perca flavescens).  (United States Fish and Wildlife Service image by Brett Billings)
Fishes of the Lower Susquehanna River Watershed: Walleye passing York Haven Dam Fish Passage
Walleye (Sander vitreus) swimming by the counter’s window at the York Haven Dam Fish Passage just upstream from Conewago Falls.

Order-Cichliformes

Family-Cichlidae

Tilapia aurea (Blue Tilapia)-exotic

During the early 1980s, Blue Tilapia (Tilapia aurea) were raised at a fish farm on Brunner Island just downstream of Conewago Falls.  During the colder months, the facility used warm water from the coal-fired steam-electric generator there to increase the temperature in the grow-out channels.  Anglers enjoyed an occasional catch of a colorful Blue Tilapia that had escaped into the Susquehanna.  During the winter, cold water was fatal to both tilapia in the river and, if the power plant experienced a shutdown, those in the fish culture facility.  As a result, efforts to raise tilapia were abandoned in favor of growing cold-tolerant species including Channel Catfish, Hybrid Striped Bass, and ornamental Goldfish.  (United States Geological Survey image by Howard Jelks)

Order-Anabantiformes

Family-Channidae

Channa argus (Northern Snakehead)-introduced

The Northern Snakehead (Channa argus), an introduced species from eastern Asia, was first reported in the Susquehanna watershed near the river’s mouth and in the nearby Octararo Creek in Cecil County, Maryland in 2016.  During 2018, it was found upstream in the river to Conowingo Dam and had advanced on the Octararo Creek into Pennsylvania.  During 2019, the Northern Snakehead was found in Deer Creek in Harford County, Maryland, the last known habitat of the endangered Maryland Darter.  (United States Fish and Wildlife Service image)
The mouth of a Northern Snakehead (Channa argus), a potentially invasive species that could catastrophically impact native aquatic animals including fish, amphibians, reptiles, and even freshwater mussels.  They had, by 2019, already infiltrated the range of the Least Brook Lamprey, Hickory Shad, Tadpole Madtom, Maryland Darter, and Chesapeake Logperch, each a species of conservation concern in the lower Susquehanna watershed.  (United States Geological Survey image)
Northern Snakehead (Channa argus) being examined after removal from the wild.  (United States Fish and Wildlife Service image by Brett Billings)

SOURCES

Argent, D. G., J. R. Stauffer, Jr., R.F. Carline, C. P. Ferreri, and A. Shiels.  1998.  Updated July 7, 2011.  Fishes: Review of Status in Pennsylvania.  pp. 177-202.  In: Inventory and Monitoring of Biotic Resources in Pennsylvania.  Proceedings of the First Conference of the Pennsylvania Biological Survey.  University Park, PA.

Bean, Tarleton H.  1893.  The Fishes of Pennsylvania: with Descriptions of the Species and Notes on their Common Names, Distribution, Habits, Reproduction, Rate of Growth, and Mode of Capture.  E. K. Myers.  Harrisburg, PA.

Haldeman, Samuel Steman.  1844.  “Natural History of Lancaster County: Pisces—Fishes”.  I. Daniel Rupp’s History of Lancaster County.  Gilbert Hills.  Lancaster, PA.  pp.472-474.

Maryland Natural Heritage Program.  2016.  List of Rare, Threatened, and Endangered Animals of Maryland.  Maryland Department of Natural Resources, 58 Taylor Avenue, Annapolis, MD 21401.

Normandeau Associates, Inc.  2012.  Shortnose and Atlantic Sturgeon Life History Studies—Conowingo Hydroelectric Project.  Final Study Report for Exelon Energy Corporation.

Pennsylvania Natural Heritage Program.  PNHP Species Lists.  www.naturalheritage.state.pa.us/Species.aspx  Accessed August 14, 2019.

Page, Lawrence M., and Brooks M. Burr.  1991.  A Field Guide to Freshwater Fishes.  Houghton Mifflin Company, New York, NY.

St. Pierre, Richard.  1999.  Restoration of American Shad to the Susquehanna River, Annual Progress Report 1998.  Susquehanna River Anadromous Fish Restoration Cooperative.

Stauffer, Jacob.  1869.  “Ichthyology”.  J. I. Mombert’s An Authentic History of Lancaster County.  J. E. Barr and Company.  Lancaster, PA.  pp.576-579.

United States Geological Survey Nonindigenous Aquatic Species Database.  http://nas.er.usgs.gov  Accessed August 18, 2019.