Non-gaurding , Pelagic

Alwife - inshore waters, eggs settle

Gizzard shad - Often move up rivers, eggs drift down

High fecundity

High early stage mortality

Non-gaurding , Pelagic

Freshwater drum eggs float on surface until hatch

Paddlefish eggs are sticky when fertilized, adhere to the first thing they touch

Non-gaurding , Benthic – fine substrate

Spottail shiners spawn on gravel and silt substrates

Non-gaurding , Benthic - Crevice

Spotfin shiners use rock crevices to hold eggs

Non-gaurding , Benthic –vegetation

Northern pike prefer flooded vegetation in backwaters

Non-gaurding , Benthic –vegetation

Banded killifish spawn gets entangled in aquatic vegetation

Non-gaurding , Benthic – coarse bottom

Lake trout and lake whitefish spawn over large broken coble areas

Non-gaurding , Benthic – stream

Pacific salmon and brown trout dig redds – clean gravel where stream water upwells

Non-gaurding , Benthic – stream

Brook trout exclusively use groundwater upwelling areas in lakes and streams

Sticklebacks make nests of algae and macrophytes and then lay eggs inside the nests

Guarding , Nests – nests of plants

Guarding means higher survival

Gaurding , Benthic – Underside of rocks

Both round gobies and Johnny darters spawn under rocks, attaching the eggs to the underside of the rocks

Aggressive defense can incur high costs to parents or death

Gaurding , Nests – gravel

Common in centrachids also lamprey, nests are often fanned to increase water flow and remove sediments

Smallmouth bass

American brook lamprey

Gaurding , Nests – Holes and burrows

Catfish and bullheads make burrows or use existing holesNoodling Time:

http://www.youtube.com/watch?v=zOjA8Puh1BM

Gaurding , Nest – fine sediment

Crappie nests associated with vertical vegetation in fine sediments

Livebearers , (none native) Mosquitofish

60 -100 progeny per brood, born live, male has modified anal fin to impregnate female

Why bear live young?

Spawning variants

Multiple strategies: Bluegill – parental care or Cuckolder

http://publish.uwo.ca/~bneff/research_beea.htm

Female mimic

Spawning variants

How often: Semelparous = once, Iteroparous = more then once

Fish evolve to spawn in different locations

Temiscamie – strain

Tributary spawner

Assinica- strain

Outlet spawner

Little Tupper strain

Shoal spawner

Why...think about the emerged fry!

Embryonic Development

What do you mean “larval fish”?

Embryo

Larvae

Adult

Diversity of Larvae

American Eel

Diversity of Larvae

Lake Sturgeon

Yellow Perch

Lake Trout

Diversity of Larvae

Brown Bullhead

Northern Pike

Largemouth Bass

Theories of Development

• Saltational: Gradual punctuated by stages of rapid, distinct change

• Gradual: All distinct stages are arbitrary

• Truth?

People are not fishYolk

Early Life History Stages

• Embryonic period

• Larval Period

• Juvenile Period

         

See Photo

Embryonic Period

Embryonic Period: Cleavage Phase

• From fertilization to recognizable predecessors of the neural plate and other organ systems.

Zebrafish embryo stages

Embryonic Period: Embryonic Phase

• Embryo recognizable as a vertebrate

• Major organ systems appear

• Ends at hatching

Embryonic Period: Free Embryo Phase

• Embryo is free of egg membranes, but still depends on yolk for nourishment

• No longer curled up, starts to resemble adult fish

• Ends when capable of capturing food

Some Ecology

Temperature and Development of Fish at Hatch

Lake Trout (Coldwater) Pygmy Sunfish (Warm water)

Temperature also effects how long egg stage lasts

Egg Size

• Larger eggs more developed at hatching

Herring: eggs, newly hatched, and 7-10 months

Newly Hatched Steelhead

Altricial: Mouths just formed at yolk depletion (Long Larvae)

Precocial: Good predators at yolk depletion (Short Larvae)

Substrate Size and Egg Survival

Yolk Size of Various Fishes

Larval Stage

Bongo Nets

Lentic vs. Lotic

• Lentic Fish often have pelagic larvae– Major period of dispersal – Major period of mortality

• Lotic Fish often have benthic larvae– Avoid being swept away– Exist for short periods, under heavy cover

Strength of Year Class

• Match/Mismatch Hypothesis– Food and other conditions are good for

survival = strong year class• Food is abundant• Predators are not abundant• Temperature is appropriate

– Cues for Spawning– Several factors can disrupt matching and

result in weak year classes

Match/Mismatch

Plankton Peak

Ideal Match

Match/Mismatch

Food Abundance

• Nutrient levels

• Temperature

• Lower-level match/mismatch dynamics

• Number of competitors

• Water chemistry

Food Abundance Fluctuations

Water Temperature

• Thermal cues for spawning

• Weather: Shallow areas variable

• Varies from system to system

• Upwelling a large cause of fluctuations in lakes

Temperature and Recruitment

Temperature and Food

0

50

100

150

200

250

300

0 5 10 15 20 25

Water Temperature (Degrees Celsius)

Nu

mb

er o

f M

idg

es

Co

llect

ed

Predator Abundance

• More predators = more mortality

• Location, location, location!

• Temperature also

Wind Effects on Temperature, Food, and Predators

Esocidae (Pikes)Grass pickerel

Northern pike

Muskellunge

Identification

Identify with pores and or branchiostegal rays

PoresPickerel – 4Pike – 5Muskie – 6-9

Branchial. RaysPickerel – 12Pike – 14-16Muskie – 16-19

Umbridae (Mudminnows)

Central mudminnow

Homocercal tail

Fin placement

Lottidae (Burbot)

Long continuous anal and dorsal fins

Homocercal tail

Single chin barbel

Aphredoderidae (Pirate perch)

"Migrating anus"

Starts here

Ends here

Big dorsal

Percopsidae (Trout-perch)

Big head and big eye

Centrarchidae – 4 genera, 8 species

MicropterusAmbloplites

PomoxisLepomis

Micropterus

Largemouth bass

Smallmouth bass

Lepomis Bluegill

Pumpkinseed

Green Sunfish

Ambloplites – rock bass

Rounded pectoral

Percidae – 5 genera, 8 species

PercaSander

Crystallaria

Etheostoma

Percina

Sander

Walleye

Sauger

Wh

ite tip

No-W

hite

tip

Brian's childhood friend Matt Sander

Rainbow darter

Johnny darter

Fantail darter

Crystal darter

Moronidae (Temperate Basses)

White bass

Yellow bass

Sciaenidae (Drums)

Gobiidae (Gobies)

Gasterosteidae (Sticklebacks)

Fundulidae (Killifishes & Topminnows)

Ictaluridae (Bullhead Catfishes)

Bullheads

Catfishes

Madtoms

Poeciliidae (Livebearers)

Osmeridae (Smelts)