Fish Ecology and Management

Workshop

Brian GundermanDr. Kevin Wehrly

Neal Godby

April 28, 2016

Outline

I. Game fish ID and general ecologyII. Habitat v. fish abundance and growthIII. Fisheries management options

- stocking- habitat protection and enhancement

Fish Habitat Requirements

Phases• Spawning/incubation• Juvenile• Adult

Habitat Components• Substrate (bottom type)• Cover• Temperature• Oxygen• Light intensity

Bluegill

Solid darkopercular flap

Dark verticalbars

Long, pointedpectoral fins

Bluegill

• Spawn on firm bottom of sand, gravel, or mud- males make nest and guard eggs and fry

• Juveniles live in shallow water with lots of cover• Adults spend more time in open water feeding

on zooplankton

PumpkinseedTend to be morecolorful and heavier-bodied than bluegills

Red spot onopercular flap

Pumpkinseed

• Spawn on sand or gravel in vegetated areas• Juveniles and adults spend most of their time

in or near cover (plants or brush)• Diverse diet that includes snails and zebra mussels

Hybridization

Pumpkinseed

Green sunfish

Ohio DNROhio DNR

Warmouth

Bluegill

Redear sunfish

Black Crappie

• Only similar species is white crappie• Distinguishing characteristics

- 7 or more dorsal spines- mottled sides (no bars)- large, paper-thin mouth

Black Crappie

• Spawn on firm bottom near brush or vegetation- prefer bays with little wave action

• Juveniles and adults more active at night- nearshore in cover during the day- offshore in open water at night

• Juveniles eat zooplankton and insects, whereasadults also eat fish

Largemouth Bass

Upper jaw extends beyond back of eyeDark horizontal band

Largemouth Bass

• Spawn on firm bottom of sand, gravel, or mud- prefer quiet bays with bulrushes or water lilies

• Brush and vegetation important for bass- juveniles: cover and food (insects)- adults: food (e.g., small bluegills)

• Adults common along edges of weed beds

Smallmouth Bass

- Upper jaw does not extend beyond back of eye- Vertical bars

Smallmouth Bass

• Spawn on gravel• Less likely to be found in vegetation than

largemouth bass• Utilize rocks and logs for cover (juveniles and

adults)

Northern Pike

Northern Pike

• Spawn in marshes or weedy bays- adhesive eggs stick to vegetation

• Vegetation provides hiding places for all life stages- protection from predators- ambush sites for prey (i.e., smaller fish)

• Adults often associated with weed edges

Muskellunge

Muskellunge• Spawn on logs or vegetation over soft sediment

- spawn farther offshore than pike- eggs not adhesive

• Spawn later than pike predation

Muskellunge• Juveniles typically associated with vegetation• Adults use various types of cover (e.g., rocks, logs, and

weeds) as ambush locations

Yellow Perch

Smaller cousin of the walleyeKey characteristics

- Dark vertical bands- Absence of sharp teeth

Yellow Perch

• Spawn over brush and vegetation- eggs in gelatinous strands

• Juveniles live in shallow water with vegetation• Adults move offshore; typically near the bottom

and associated with cover• School during the day and rest

at night

Walleye

No distinct vertical bars Sharp teeth Reflective eyes White tip on tail

Walleye

• Spawn over gravel and cobble- nonadhesive eggs- spaces between rocks = hidden from predators- no shifting silt or sand

• Avoid bright light- deeper water during day- cover

Trout

Trout• Brook, rainbow, and brown trout generally

spawn over gravel in streams• Lake trout spawn over cobble reefs• Most trout populations in inland lakes supported

by stocking• All species require cold, well-oxygenated water

- small percentage of inland lakes meet thisrequirement during the summer