Phylum Chordata—animals with a notochord, gill clefts and a dorsal nerve cord at some
stage of their life, most species with sexual reproduction (dioecious)
SubPhylum Vertebrata—animals with a vertebral column
Class Agnatha—jawless vertebrates
Family Petromyzontidae—lampreys
•Naked (no scales) eel-like body, no bones
•Jawless mouth with a circular sucking disc with rasping teeth
•Dorsal and caudlal fins but no paired fins,
•7 gill openings, no gill covers, single median nasal opening between eyes.
Adult lampreys 0.3-0.8 m long
Life cycle—many species anadromous and parasitic—spawn in freshwater, develop into a blind
and toothless ammocoetes larva that burrows into mud in streams and lakes--detritivore.
Larva 5-30 cm
Lampreys spawning in stream gravel
Ammocetes larvae
Metamorphosis into a an adult at 1-7 yrs, followed by migration
to seaSome freshwater species that are not parasitic spawn
soon after metamorphosis and die. All adults die after spawning
Lake trout parasitized by P. marinus
Adult of most species parastic on salmonids—ruptures
skin and sucks blood and fluids.
Impact of P.marinus on great lakes trout
Relationships of Freshwater Fishes
Paleoniscoid fishes
Polypteridae
Polyodontidae
Most modern freshwater fishes are bony (Osteichthyes), and
ray-finned (Actinopterygii).
Of these there are two groups: the ancient Paleoniscoid
Acipenseridae (“old”fishes) and the modern (Teleost fish).
Lepisosteidae • This group of ancient “relict” fishes have prospered in the
ancient large river systems, which date back to the Mesozoic
Amiidae
era, and are remnants of large shallow inland seas.
Hi
•they survive in competition with modern teleosts and till recent
times, have been very successful.
An
Cl
Si
Ch
Cy
S
E
Gad
Ga
P
Modern Teleosts
Paleoniscoids share one or more of a set of primitive
fish characteristics with lungfishes and coelocanths:
•Bony (ganoid) plates on their scales
•A heterocercal tail
•Lungs that can function as a swim bladder
•Upper jaw fused to the skull
•A spiral valve intestine
•A spiracle (vestigial first gill)
Family Polypteridae—bichirs—primitive fish found in large African rivers.
possess all the primitive paleoniscoid characters
•Bony (ganoid) plates on their scales
•A heterocercal tail
•Lungs that can function as a swim bladder
•Upper jaw fused to the skull
•A spiral valve intestine
•A spiracle (vestigial first gil)
Plus a number of specialized characters
Multiple dorsal finlets, a special type of lobed pectoral fin, a pair of projections from the
upper jaw
Family Acipenseridae—sturgeons
•Body with 5 rows of armoured bony scutes, no teeth
•no scales, skeleton mostly cartilaginous
•tail heterocercal, upper jaw fused to braincase, spiral valve present
•Swim bladder but no lung, spiracle present in most species
•Snout extending beyond ventral sucking mouth, 4 sensory barbels
•Occur along all coastlines and major rivers in N/A, Europe and Asia,
•spawning must occur in freshwater
Cool water fish that feed mainly on benthic
invertebrates, but large ones can feed on fish at
lot at night.
Sturgeons are famous for their eggs (caviar) and
for the gelatin made from their swim bladder
Sturgeon are large powerful fish, that
can reach hundreds of kg and live for
well over 100 yr.—a large female can
produce ~ a million eggs.
When they get really large they are
usually piscivorous
Russian caviar
Red caviar on
eggs
Family Polyodontidae—paddle fishes
•Snout long and can detect electric fields of small prey, filter-feeders with no teeth, gill rakers
long and fine.
•Tail heterocercal, no scales, skeleton mostly cartilaginous.
•Skin is smooth and scaleless, operculum greatly elongated and covering a small spiracle
(vestigial gill)
•Swim bladder present but lung absent, spiral valve present
•Two species, one in the Mississippi system (<2m), and one in the Yangtze in China (<5m).
•There are important spawning sites for paddle fish on the Yellowstone R., Montana, a
tributary of the Missouri R.
Polyodon spathula
•The paddle fish was historically found in the Great Lakes.
•Paddlefish, like sturgeon, are highly prized for their caviar.
•Both have survived virtually unmodified for > 300 million yr, but are now highly threatened by
overharvesting and by damming/fragmentation of rivers since they are highly migratory fish.
•They also need clean, gravelly and sandy river bottoms on which they spawn, and siltation and pollution
are both big problems for them.
Family Lepisosteidae—garpikes
•body covered with bony ganoid scales (diamond shaped scales plated with bone)
•tail homocercal, not heterocercal
•elongated pike-like mouth with many sharp teeth along the edge of the upper and lower jaw.
•upper jaw fused to the braincase
•lung present, can function both in respiration and as a swim bladder.
•Intestine has a spiral valve.
•Gars are warm-water
fishes.
•In Canada, the longnose
gar (Lepisosteus osseus) is
found in the St.Lawrence
system and in southern
Ontario, mainly Lake Erie.
Ganoid scale
Natives used ganoid scales for jewellry
Family Lepisosteidae: the alligator gar, Atractosteus spatula
The alligator gar lives in the lower Mississippi River, and in lakes of the american
southeast.
It can reach >100 kg.
Alligator Gars inhabit sluggish pools and backwaters of large rivers, swamps, bayous, and lakes.
They sometimes enter brackish waters and occasionally saltwater. As you might have figured
they feed mainly on fish.
Although gars don’t build nests and exhibit parental care, they have “toxic” young.
Family Amiidae—bowfin, Amia calva
•Elongate olive coloured body (up to 1m, 6 kg), with a very long dorsal fin, no spines in fins.
•tail homocercal, large “eyespot” on the dorsal half, scales cycloid (no ganoin)
•Large bony plates on the skull, with large teeth (omnivore/piscivore), upper jaw fused to the
braincase.
•Skeleton, including much of the skull, largely cartilaginous.
•Intestine has a vestigial spiral valve.
•A distinctive bony gular plate is located on the under-surface of the throat between the
lower jaws
•The bowfin has an air bladder that can function as a lung—it is often found in shallow
stagnant pools on river flood plains, and will gulp air when there is little oxygen in the water.
The bowfin is common in Quebec and Ontario within the St. Lawrence system and down into the
Appalachian states—warm water fish with similar thermal preferences to bass.
•Bowfins are spring spawners.
• the male clears an area in the mud for the female to lay eggs in, and then he fertilizes them.
•He hovers nearby and aggressively protects the eggs and the fry after they emerge for several
weeks. At spawning time the inside of the male’s mouth becomes turquoise.
The gular plate in the lower jaw
The Teleost fish
Po
Pol
Ac
Lep
The success of teleost fishes can be ascribed to:
•rapid and agile swimming
•buoyancy control,
•efficient way of circulating water through the gill chamber,
•wide range of feeding niches.
These improvements result from the following adaptations:
Am
•maneuverable fins, telost tail fin (homocercal), light flexible
scales
Osteoglossidae •swim bladder—also leads to improved hearing
Hiodontidae
•branchiostegal rays, interopercular bones, opercular bones
•Articulating (movable) upper jaw (premaxillary and maxilla)
Elopidae
make the mouth more flexible.
Anguillidae
Clupeidae
Engraulidae
Ictaluridae
Characidae
Cyprinidae
Catostomidae
Salmonidae
Osmeridae
Esocidae
Gadidae
Gasterosteidae
Cottidae
Centrarchidae
Percidae
Teleost tail skeleton
Uroneural bones
(modified neural arches
hypourals
The Teleost fish
Po
Pol
Ac
Lep
Am
The success of teleost fishes can be ascribed to:
•rapid and agile swimming
•buoyancy control,
•efficient way of circulating water through the gill chamber,
•wide range of feeding niches.
These improvements result from the following adaptations:
•maneuverable fins, telost tail fin (homocercal), light flexible
scales
Osteoglossidae •swim bladder—also leads to improved hearing
Hiodontidae
•branchiostegal rays, interopercular bones, opercular bones
•Articulating (movable) upper jaw (premaxillary and maxilla)
Elopidae
make the mouth more flexible.
Anguillidae
Clupeidae
Engraulidae
Ictaluridae
Characidae
Cyprinidae
Catostomidae
Salmonidae
Osmeridae
Esocidae
Gadidae
Gasterosteidae
Cottidae
Centrarchidae
Percidae
The Teleost fish
Po
Pol
Ac
Lep
Am
The success of teleost fishes can be ascribed to:
•rapid and agile swimming
•buoyancy control,
•efficient way of circulating water through the gill chamber,
•wide range of feeding niches.
These improvements result from the following adaptations:
•maneuverable fins, telost tail fin (homocercal), light flexible
scales
Osteoglossidae •swim bladder—also leads to improved hearing
Hiodontidae
•branchiostegal rays, interopercular bones, opercular bones
•Articulating (movable) upper jaw (premaxillary and maxilla)
Elopidae
make the mouth more flexible.
Anguillidae
Clupeidae
Engraulidae
Ictaluridae
Characidae
Cyprinidae
Catostomidae
Salmonidae
Osmeridae
Esocidae
Gadidae
Gasterosteidae
Cottidae
Centrarchidae
Percidae
Articulating jaw bones can allow a more flexible mouth
Here the fish uses this in combination with a flexible operculum to
generate suction—an important factor when you are feeding in a fairly
dense fluid medium
Taken to an extreme in filter-feeders e.g. clupeomorphs—herrings.
Po
Pol
Ac
Lep
The Teleost fishes—’true bone’
According to Greenwood (1966) there are 4 main lines
(superorders) of Teleosts.
Each contains families that occur in Canadian freshwaters.
Am
Osteoglossidae
Hiodontidae
Elopidae
Anguillidae
Clupeidae
Engraulidae
Ictaluridae
Characidae
Cyprinidae
Catostomidae
Salmonidae
Osmeridae
Esocidae
Gadidae, Percopsidae
Gasterosteidae
Cottidae
Centrarchidae
Percidae
•Osteoglossomorphs represented by
the Hiodontids (Goldeyes and Mooneyes)
•Elopomorphs represented by the
Anguillids (Eels—distinctive type of larva)
•Clupeomorphs (Herring type fishes)
alewifes and shads (Clupeidae)
•Euteleost fish, contains most of our
common fish families.
Osteoglossomorpha—’bony tongues’—bones on tongue opposing teeth on roof of mouth
Family Hiodontidae—Goldeyes and mooneyes
•Herring shaped fish, with a blunt nose teeth on their upper and lower jaws and tongue, and large eyes
with reflective gold/silver irises (night vision), very long anal fin, > 25 rays, all fins soft-rayed, pelvic fins
abdominal, no adipose fin.
•Coolwater fish that live in the middle reaches of turbid rivers (Eg Saskatchewan, Peace, Athabasca, and
Missouri Rivers and associated lakes)—also found in most of the northern Canadian lakes and rivers
associated with the Hudson Bay drainages.
•prey on a variety of invertebrates, and become fairly piscivorous as adults.
•release neutrally buoyant eggs that drift downstream and hatch in the lower reaches of the drainages the
fish then gradually migrate upstream to spawn
http://www.sunsite.ualberta.ca/Projects/Bio-DiTRL/t/t53780604.jpg
The mooneye—Hiodon tergisus
•Iris golden only on the top half of the eye (all around in goldeye)
•Dorsal fin begins anterior to anal fin (even or posterior in goldeye)
•Keeled region of belly extends from the base of pelvics to anal fin (all the way from
pectorals to anal in goldeye)
Family Osteoglossidae—the bony tongue
http://www.primitivefish.com/ZZPpolli1.JPG
Phareodus encaustus an osteoglossid
from the Green River Formation in
Wyoming
Eohiodon—a likely ancestor of Hiodon
was also present
http://www.geoclassics.com/fish/fish_$225_ph.jpg
Another Green River fish fossil –Can you recognize these families?
http://www.fossilmuseum.net/Fossil_Galleries/Green_River_Formation_Fish/Phareodus2/Phareodus2.htm
Family Anguillidae—eels
•Elongate fishes with tube-shaped bodies, pointed heads and the dorsal, caudal and anal
fins continuous around the posterior end of the body, fins soft-rayed.
•Paired pectoral fins, but no pelvic fins.
•Scales are very tiny and soft
•Catadromous fishes—live in freshwater and return to the sea to spawn in tropical oceans,
the Sargasso Sea.
•Eggs hatch into tiny transparent, planktivorous larvae called leptocephalus (“tiny head”)
which drift with ocean currents
•As they approach shallow water they metamorphose into glass eels which live in
esturaries, and then become elvers, which begin to migrate up rivers in early summer.
Glass eels
Leptocephalus larvae
around 1cm long and
nearly transparent.
The pan-Atlantic
spawning migration of
the eel likely originated
a long time ago
It seems less bizarre in
the Cretaceous Atlantic
Ocean than in the
modern one
Many elopomorphs are important marine game fish
The tarpon Megalops. This fish lives
in brackish coastal waters and spawns
in coastal marshes
The bonefish, Albula vulpes is also a
brackish water fish
All of these fish have leptocephalus larvae, which are similar to those of eels.
Family Clupeidae—herring family
•Silvery laterally compressed fish with countershading adapted for pelagic life
•Swim bladder abuts against hearing centre in the brain
•sawtoothed keel on their belly, supported by a row of ventral keelbones
•silvery deciduous scales (cycloid), soft-rayed fins, pelvic fins abdominal, no adipose fin.
•gill rakers numerous, long and very fine,
•capable of pumping water through the gill chamber
•most abundant in coastal waters, filter-feeders on zooplankton, very important in food webs of
coastal marine waters and in many coastal lakes.
•clupeids congeragate to spawn near river mouths, several hundred km from their feeding areas.
Gill rakers
Adult alewives are 10-15 cm long
The alewife, Alosa pseudoharengus, a warmwater zooplanktivore, lives in estuaries in eastern NA,
but has establish many inland populations, most notably in the Great Lakes, where it invaded
through the Erie canal.
The alewife became extremely abundant in Lakes Ontario and Michigan following the collapse of the
lake trout populations in these lakes.
Estuarine populations spawn in river mouths during April and May, Lake populations spawn in river
mouths in early spring. After the lakes warm up they become pelagic planktivores.
The american shad Alosa sapidissima is an anadromous clupeid that spawns
in rivers along the east coast of North America. This fish is both a popular
sportfish and delicious as well. It has a life cycle similar to salmon. They
typically spend about 5yr at sea during which they move more than 10,000 km.
As soon as the young hatch in the spawning rivers they begin to move downstream
and spend their first fall and winter as plankton feeders in the estuary.
The Gizzard Shad, Dorosoma cepedianum, is a clupeid that can complete its whole life cycle in
freshwater.
•Gizzard shad are characterized by their inferior, sub-terminal, toothless mouth and gizzard-like (grinding)
stomach. The last ray of their dorsal fin is extended into a longish filament.
•They spend their entire adult lives in fresh or brackish waters along the east coast of North America. They are
also abundant in the Great Lakes.
•When large they are primarily deposit-feeders ingesting mud and digesting organic matter/bacteria etc.
although they are plankton feeders when they are smaller.
•They are tolerant of highly turbid eutrophic waters.
Knightia—a small
Eocene freshwater
herring
Gizzard shad are used as feed, fertilizer or fish bait, but have no value as sport or
commercial fish.
http://www.dec.state.ny.us/website/dfwmr/fish/fishspecs/gizzshad.gif
Diplomystus—another Eocene herring, more like the modern
american shad, it became a piscivore on small herrings when larger
(up to 50 cm)
http://www.geoclassics.com/fish/fish_$130_d.jpg
Po
Pol
Ac
Lep
Am
Osteoglossidae
Hiodontidae
Elopidae
Anguillidae
Clupeidae
Engraulidae
Ictaluridae
Characidae
Cyprinidae
Catostomidae
Salmonidae
Osmeridae
Esocidae
Gadidae, Percopsidae
Gasterosteidae
Cottidae
Centrarchidae
Percidae
Euteleost fishes
•Ostariophysi (true freshwater fish) –
Weberian apparatus & fright substance. ,
Cyprinids (minnows), Catostomids (suckers)
and the Ictalurids (catfish) families.
•Protacanthopterygii –salmonids(trout,
whitefish, graylings), esocids(pikes), and the
osmerids (smelts)
•Paracanthopterygii—burbot (Gadidae) and
by the trout perch (Percopsidae)
•Acanthopterygii –spiny rayed families
,sticklebacks (Gasterosteidae), sculpins
(Cottidae), sunfishes (Centrarchidae), and
perches (Percidae).
The Ostariophysi are the most interesting group from the zoogeographic perspective
•Very low saltwater tolerance
Origin of ostariophysi
The distribution of cyprinids
strongly reflects the arrangement of
continents during the late Cretaceous
Area of highest
cyprinid diversity
Catfish on every
Continent
•Cyprinids are the most abundant Freshwater
fish family in Asia, NA and Africa, and virtually
absent from SA, Australia, Antarctica and
Madagascar.
•the catfish are found on every continent except
Antarctica—likely the Ostariophysan ancestor
very catfish-like
Ost
Gond Laur
Ch Sil Cyp Cat
•Explain??
•Catfish are by far most diversified in SA.
•Characids are highly diverse, found only in SA.
•Catostomids are found only in east Asia and
NA?
•Large benthic feeding cyprinids found only in
west Asia to Europe.
Family Ictaluridae—north American catfishes and bullheads
•body without scales, 4 pr barbels in front part of head, each pectoral fin with a hard
venomous spine that can lock into place
•Flatenned head with small eyes, a single dorsal fin with a solitary spine at the leading
edge, and an adipose fin behind it.
•No true teeth on jaws, reduced swim bladder, generally benthic
•Generally nocturnal feeders on bottom invertebrates
•Well developed chemosensory cells all over body and well developed lateral line system,
depend little on vision.
•Entirely freshwater fishes that cannot disperse through seawater
•Very popular eating fish, in the southern US highly prized for aquaculture.
Channel catfish, Ictalurus punctatus, a prized game fish found in large cool-warm
water rivers—does not occur in Alberta but may have occurred here in the past
according to archeological evidence.
The stonecat, Noturus flavus, the only catfish that occurs in Alberta—
found in the Milk River.
Yellow bullhead
Ictalurus natalis
Brown bullhead
Ictalurus melas
Bullheads are omnivorous warm water fish that live
in lakes and rivers. Spawning occurs in May and
June in slow moving streams, creek mouths, or
along the shores of lakes
Family Cyprinidae
•Conservative body shape, with soft-rayed fins, single dorsal, no adipose fin, abdominal
pelvic fins, usually drab coloured with darkish stripes along the side of the body,
•large eyes, toothless jaws, but with several rows of pharyngeal teeth
•Mouth small, terminal to subterminal, with thin flexible lips on an articulating premaxilla
•a two-part swim-bladder with the front part linked by bones to the hearing center—Weberian
apparatus—they have excellent hearing.
•Generally feed either on plankton, mud, or algae, but some can become large piscivores.
•Strong tendency to schooling behaviour, fright substance,
•usually live in small lakes, and slow moving streams, nearshore.
•Known for offshore (usually plankton feeding) movements at night, and onshore (into the
weeds for protection) movements during the day.
•Most spawn nearshore and have some type of nest-building or parental care and become
brightly coloured while mating.
•Mostly warm-water species, with a broad thermal range, but low tolerance for salt water.
•Northern redbelly dace, Phoxinus eos, a common Canadian
minnow usually found nearshore in small lakes.
•Most N/A species < 10 cm, but many european species
large, and popular game fish.
Fathead minnow –Pimephales promelas
Anterior half-ray
Scales larger toward the rear
Lateral line stops near the front
Adult male fathead minnow in full breeding colouration with large nuptial tubercles—
function in male display and fighting, many cyprinids have this
P.Promelas habitat
Adult female
Creek chub Semotilus atromaculatus
Lake chub Couesius plumbeus
Longnose dace—Rhinichthys cataractae—a very common stream and
river minnow in Alberta, one of the most abundant species in the
Oldman R.
Blacknose dace—Rhinichthys atralatus
Pikeminnow or squawfish—Ptychocheilus oregonensis, a cool water fish native to
interior mountain ranges, can become large and piscivorous—an important
predator on young salmonids.
Found in Alberta but only in the Peace River drainage which originates in the
interior of BC.
The carp—a cyprinid introduced to Europe and North america from Asia, which
most zoogeographers believe is the original home of the Cyprinidae.
The common carp
The mirror carp
An important aquaculture species
•Family Catostomidae—suckers
•Suckers are minnow-shaped fish, with subterminal mouths, and thick papillate lips. Like
minnnows they have toothless jaws, but rows of pharyngial teeth.
•Suck up bottom debris, feed on mud, periphyton and small benthic invertebrates.
•Food is broken up by pharyngeal teeth and digested in a long winding intestine—stomach not
distinct from intestine
•Suckers have similar swim bladder and Weberian apparatus to minnows
•Suckers are cool water fish that spawn in spring in small creeks or in shallow areas of lakes
Longnose sucker
Catostomus catostomus
Common sucker
Catostomus commersoni
Moxostoma macrolepidotum—shorthead redhorse—note the slightly more terminal
mouth than Catostomus, and larger but fewer scales.
Moxostoma
love burrowing
mayflies.
They are very
abundant right
around
Lethbdridge.
http://coopunit.forestry.uga.edu/unit_homepage/pics/robust
The quillback sucker—Carpiodes cyprinus has the largest scales in the family (>
2cm) and is also common in the lower Oldman. It is a big macrophyte eater.
http://fish.dnr.cornell.edu/nyfish/Catostomidae/quillback.jpg
Po
Pol
Ac
Lep
Am
Osteoglossidae
Hiodontidae
Elopidae
Anguillidae
Clupeidae
Engraulidae
Ictaluridae
Characidae
Cyprinidae
Catostomidae
Salmonidae
Osmeridae
Esocidae
Gadidae, Percopsidae
Gasterosteidae
Cottidae
Centrarchidae
Percidae
Euteleost fishes
•Ostariophysi (true freshwater fish) –
Weberian apparatus & fright substance. ,
Cyprinids (minnows), Catostomids (suckers)
and the Ictalurids (catfish) families.
•Protacanthopterygii –salmonids(trout,
whitefish, graylings), esocids(pikes), and the
osmerids (smelts)
•Paracanthopterygii—burbot (Gadidae) and
by the trout perch (Percopsidae)
•Acanthopterygii –spiny rayed families
,sticklebacks (Gasterosteidae), sculpins
(Cottidae), sunfishes (Centrarchidae), and
perches (Percidae).
Premaxilla can be protracted, pulled forward like a lip
•Double dorsal fin
Spiny fin ahead of soft fin
Acanthopterygian
characteristics
are considered to be those of
advanced modern teleosts
•Swim bladder not linked to
gut—physoclistous as opposed
to physostomatous.
•Scales ctenoid (as opposed to
cycloid)
•Fin rays spiny, sharp and not soft or flexible
•Pelvic fins forward (thoracic as opposed to abdominal position)
•Pectoral fins along the side of the body
•Head and operculum with one or more spines
The trout (Protacanthopterygii) has the
ancestral condition for each of these characters
Protacanthopterygii
Family Esocidae—pikes and pickerels
•body elongate, length, snout long, tail slightly forked,
•fin rays soft, dorsal fin single, pelvics abdominal, l
•ive in weedy littoral of lakes and slow moving rivers, cool water fish
•ambush predators on fish and invertebrates
•The northern pike, Esox lucius, is the most widespread (circumpolar) of all the pikes.
•Adults spawn along shores of lakes and flooded rivers in very early spring.
•Eggs are laid on vegetation and young hatch and remain stuck to vegetation for a week or so
usually until the food populations grow.
•The young feed on invertebrates and other small fish including their own species.
•Young pike grow very rapidly often reaching 15 cm at the end of their first year. Adult female
pike can reach weights > 15 kg. Most males never exceed 2kg.
The chain pickerel—Esox niger, usually < 2 kg
The redfin pickerel—Esox americanus, usually < 1 kg
http://www.nae.usace.army.mil/recreati/hel/ContoocookRiverWebsite/UnderwaterLife/ChainPickerel/FI0023_1m.jpg
Esox vermiculatus—grass pickerel
Esox masquinongy—the muskellunge the largest of the pikes > 30 kg
Family Osmeridae—smelts
•Small, but elongate pelagic fishes, large eyes (nocturnal), soft-rayed fins, pelvics abdominal, single
dorsal, caudal fin somewhat forked and much wider than body.
•predators on zooplankton and marine larvae in coastal seas, estuaries, sometimes forming
landlocked populations in lakes. Many are anadromous. Cycloid scales, teeth on their upper and
lower jaws, distinctly countershaded.
•Rarely exceed 20 cm. Most spawn on beaches, or run up small streams. Cold water fishes.
•Although small, they are a highly prized food fish—”smelting” is an important cultural activity
Beach seining for smelt
•The rainbow smelt is a glaciomarine relict. It
forms land-locked populations in lakes whose
basins are remnants of inland glacial seas such as
the Champlain Sea.
•The range has been greatly increased through
human introductions.
Family Salmonidae—whitefish, trout and salmon
•Soft-rayed fins native to cold waters throughout the northern hemisphere, dorsal fin central and
single, pelvic fins abdominal, adipose fin present. Scales cycloid.
•Always spawn in freshwater, adults either landlocked or anadromous, young usually have “parr”
markings.
•Three subfamilies are recognized each of which are sometimes considered as families.
•More scientific studies have been done on salmonids than any other fish.
Young salmonids have distinct parrmarks
A hatchery strain of rainbow trout
Salmonids from hatcheries have been
introduced to practically all continents.
Family Coregoninae—the whitefish
Silvery fish, with large scales, and toothless jaws.
Fall spawners on beaches, no redds
Tip of dorsal fin extending
beyond the remainder of the fin
Mouth subterminal
The lake whitefish, Coregonus clupeaformis, is mainly a benthic feeder in large lakes, it has a
broad diet, including sphaeriids, chironomids, mysids, amphipods and small fish. When it is
small it feeds mainly on zooplankton.
Highly variable in maximum size, can reach > 4 kg,
but in many lakes there a dwarf races that feed on zooplankton their whole lives and rarely
exceed 50 kg.
Populations of dwarf and normal fish, genetically isolated, can coexist within the same lake.
Coregonus artedi—cisco , lake herring, or tullibee
Mouth terminal with
lower lip extending
beyond upper lip
Tip of dorsal not extending
beyond the remainder of
the fin
The lake herring are smaller, than lake whitefish, usually < 0.3 kg, and feed on small
zooplankton or Mysis throughout their life.
Interestingly, dwarf lake whitefish never evolve in a lake that contains C. artedi
Prosopium williamsoni—the mountain whitefish
Prosopium coulteri—
the pygmy whitefish
Stenodus leucichthys—the inconnu
• is a large whitefish found in North America, northern Europe and Asia.
•The fish has a large mouth with a protruding lower jaw and a high and pointed dorsal fin. It is
generally silver in color with green, blue or brown on the back. The meat is white, flaky and
somewhat oily.
•Young are planktivores, and then switch to Mysids and fish larvae, and then to larger fish.
•The fish live in lakes and rivers and in the brackish water at the outlets of rivers into the
ocean.
•may migrate 1500 km (1000 miles) to spawn.
•An adult fish weighs from 14-25 kg
http://www66.tok2.com/home2/ichthy/image3/inconnu3.jpg
Subfamily Thymallinae—the graylings
Light sprinkling of black spots on
anterior dorsal
Large colourful dorsal fin
Mouth terminal with small teeth
The genus Thymallus has a circumpolar arctic distribution. Known in the Athabasca and
Peace drainages in Alberta. A small isolated population exists in the upper Belly River in
Waterton Park and Montana—they have been introduced to some foothills lakes in S. Alberta.
Require cold streams or lakes. Bury their eggs in gravel redds
Subfamily Salmoninae—trout, salmon and char
•Salmonids with small to tiny scales, usually spotted either with dark or coloured spots. Jaws
with teeth including maxillary and premaxillary bones, plus vomer.
•Strong migratory tendency, often anadromous, with homing fidelity to spawning grounds
(straying usually < 1%).
•Stream spawning presumably reflects the well aerated environment protected from most large
predators
•Males arrive first on the spawning grounds, fight to establish a hierarchy; female arrives later
and builds a redd in well aerated gravel, and males courts the female with a quivering motion
of its body (dominant males closest), if rival males also court, fighting and display are common.
•redds are usually in pool-riffle transition zones.
•The exception is the lake trout, a char, which spawns without building a nest.
•What are the advantages and disadvantages of anadromy?
Oncorhynchus nerka—the sockeye salmon, landlocked variety called kokanee
Note the large
anal fins on Pacific
salmon
male
female
Oncorhynchus mykiss—steelhead, landlocked varieties are called rainbow trout.
Golden trout
A landlocked
subsp from
California
Oncorhynchus clarkii—cutthroat trout
Coastal
Yellowstone
Colorado River
Rio Grande
Bonneville
Westslope
Fragmentation has led to
subspeciation in cutthroat trout
Coastal cutthroat
O. Clarki clarki
westslope cutthroat
O. Clarki lewisi
Humboldt cutthroat
O. Clarki spp.
Yellowstone cutthroat
O. Clarki bouvieri
Snake River cutthroat
O. Clarki behnkei
Colorado River cutthroat
O. Clarki pleuriticus
Lahontan cutthroat
O. Clarki henshawi.
Rio Grande cutthroat
O. Clarki virginialis
Greenback cutthroat
O. Clarki stomias
Bonnevillecutthroat
O. Clarki utah
Maps & trout pictures from
Behnke and Tomelleri 2002
Salvelinus namaycush
The Bull trout
Large river form
Stream resident form
•The Bull trout was once very
abundant on the eastern
slopes large numbers
migrated a considerable
distance down prairie rivers
Present eastern limit in Canada
•Although considered an
endangered species many
small streams still have
healthy populations
•Migrant prairie bull trout
have largely disappeared
as a result of large dams
built on the North and
South Saskatchewan
River Systems.
Migratory bull trout move upstream to spawn in small tributaries where they select
spawning gravels that are fairly fine and loose with upwelling groundwater
•A nice bull trout from below the Oldman Dam; Since 1992 fishing regulations
stipulate that all bull trout caught must be released
•Some of the bull trout in this section are over 10 lbs.
•These trout are blocked by the dam and are unable to return home to spawn in the
tributaries to the Oldman.
Salvelinus fontinalis—Eastern brook trout
Salvelinus fontinalis
Native range
Expanded range
Salmo trutta—brown trout (introduced to NA from Europe)
Salmo salar—atlantic salmon
Precocious male
Po
Pol
Ac
Lep
Am
Osteoglossidae
Hiodontidae
Elopidae
Anguillidae
Clupeidae
Engraulidae
Ictaluridae
Characidae
Cyprinidae
Catostomidae
Salmonidae
Osmeridae
Esocidae
Gadidae, Percopsidae
Gasterosteidae
Cottidae
Centrarchidae
Percidae
Euteleost fishes
•Ostariophysi (true freshwater fish) –
Weberian apparatus & fright substance. ,
Cyprinids (minnows), Catostomids (suckers)
and the Ictalurids (catfish) families.
•Protacanthopterygii –salmonids(trout,
whitefish, graylings), esocids(pikes), and the
osmerids (smelts)
•Paracanthopterygii—burbot (Gadidae) and
by the trout perch (Percopsidae)
•Acanthopterygii –spiny rayed families
,sticklebacks (Gasterosteidae), sculpins
(Cottidae), sunfishes (Centrarchidae), and
perches (Percidae).
Premaxilla can be protracted, pulled forward like a lip
•Double dorsal fin
Spiny fin ahead of soft fin
Acanthopterygian
characteristics
are considered to be those of
advanced modern teleosts
•Swim bladder not linked to
gut—physoclistous as opposed
to physostomatous.
•Scales ctenoid (as opposed to
cycloid)
•Fin rays spiny, sharp and not soft or flexible
•Pelvic fins forward (thoracic as opposed to abdominal position)
•Pectoral fins along the side of the body
•Head and operculum with one or more spines
The trout (Protacanthopterygii) has the
ancestral condition for each of these characters
Family Gasterosteidae
Most sticklebacks are
marine or estuarine fish.
They are cool to warm
water fish that consume
Zooplankton and benthic
invertebrates.
Gasterosteus aculeatus—the three-spine stickleback
Pungitius pungitius—the nine-spine stickleback
They nest in river mouths
and along the margins of
lakes in spring and early
summer.
Adult sticklebacks rarely
exceed 8 cm in length
4-horned sculpin, Myoxocephalus quadricornis
Most adult sculpins in freshwater
are < 12 cm long.
Sculpins are mostly marine, but many species have established land-locked
populations in cold rivers and deep lakes. They are cold water fish that spawn in
spring. The consume benthic invertebrates and occasionally small fish.
Yellow perch—Perca flavescens
Yellow perch are cool water fish, that eat zooplankton when small, switch to
benthic invertebrates around 10 cm and fish around 15 cm. Adults can reach
sizes of >30 cm but are often stunted < 15 cm. Perch are most common in
lakes but also occupy slow moving rivers. They spawn in spring around creek
mouths.
Walleye and sauger are cool water piscivores, that spawn in spring and early
summer on gravel bars in rivers and in lakes. Sauger seem to prefer more
turbid rivers than walleye
Yellow walleye—Stizostedion vitreum
Sauger –Stizostedion canadense
Smallmouth bass—Micropterus dolomieui
Bass are warm water fish that feed on fish and crayfish. They live along
gravelly shallow areas of lakes and in rivers. Spawning occurs in late
spring. Male bass spend several weeks protecting their young after they
hatch.
Pumpkinseed sunfish—Lepomis gibbosus
Pumpkinseeds are warm water fish that feed on mainly on snails and other
invertebrates.
They live along shores of lakes and slow moving rivers.
Spawning occurs throughout summer.
Bluegill sunfish—Lepomis macrochirus
Bluegills are warm water fish that feed on mainly on littoral invertebrates.
They live along shores of lakes and slow moving rivers.
Spawning occurs throughout summer.
Family Gadidae—cod family
•Deepwater bottom oriented fishes cold water fish, on and off the continental shelves,
•Elongate tapered bodies, usually long dorsal (2 or 3 sections) and anal fins,closely
approximating but separate from the caudal fin, pelvic fins thoracic, no spines,
•tiny cycloid scales
•Large terminal or subterminal mouths often with one or more barbels
•carnivores, prey on fish and benthic invertebrates
•Spawns in large aggregations during winter,
•Usually with pelagic larvae, that settle as juveniles
The burbot, a freshwater cod, Lota lota
The burbot is a cool water fish that lives in deep lakes. It eats invertebrates and
small fish. It spawns from January to March, in shallow water over sand and
gravel bottomed areas. The fishes spawn at night with a dozen or so individuals
forming a writing mass. The eggs develop in the sand and hatch in spring.
Family Percopsidae—the troutperch
•these little fish have an interesting mixture of ancestral and derived characteristics,
resembling both trout and perch.
•Premaxilla not protractile,pelvic fins subthoracic (close to but slightly behind pectorals),
weakly developed spines in dorsal and anal fin. d
•Dorsal fin single, adipose fin present, scales cycloid anteriorly, ctenoid posteriorly.
•Eyes moderately large, mouth moderately large and subterminal, small teeth on premaxilla
and lower jaw
Adults 8-10 cm long
The troutperch—Percopsis omiscomaycus is common in the lower Oldman, Bow and
Saskatchewan rivers, and is also common in deep lakes.
•Generally night feeders on benthic invertebrates. Many larger fish eat them
especially walleye.
•They are hosts for the intermediate stage of a tapeworm Triaenophorus
stizostedionus whose definitive host is the yellow walleye.
Temperature preferences of fish.
Coldwater fish—generally prefer summer temperatures < 18C. Can feed actively
and grow during winter under ice, and usually spawn in early spring or late fall.
Coolwater fish—generally prefer summer temperatures between 18-22C. Can
feed actively during winter but usually grow little. Usually spawn in spring to
early summer
Warmwater fish—generally prefer summer temperatures between 20-25C. Very
inactive and usually feed little during winter. Usually spawn in late spring to midsummer.
Cold
Cool
Warm