Largemouth Bass

icropterus salmoides

Species Overview

Physical Characteristics

Largemouth bass display a powerful, deep-bodied build with a large head comprising approximately 1/3 of their total body length. Their coloration ranges from dark olive-green to almost black on the dorsal surface, fading to lighter green or yellowish-green on the sides, with a distinctive jagged dark lateral band running horizontally along the midline. The belly is typically white or cream-colored.

They have two dorsal fins that are almost separated, with the first having 9-10 hard spines and the second having 12-13 soft rays. The mouth is exceptionally large—the upper jaw extends well beyond the rear margin of the eye, distinguishing them from smallmouth bass. Their eyes are typically bronze to reddish in color. Coloration intensity varies based on habitat, water clarity, and mood, with fish from darker waters appearing almost black while those from clear waters show brighter green coloration.

Fishing Information

Size Range

12-16 inches

Best Lakes

Central Chain

Peak Season

Spring, Summer, Fall, Winter (Ice Fishing)

Best Baits

Soft Plastic Baits Hard Baits – Topwater Hard Baits – Subsurface Jigs

Fishing Guide

Best Fishing Times:

Dawn, Morning, Dusk, Night
Peak Fishing Seasons:

Spring, Summer, Fall, Winter (Ice Fishing)
Recommended Lures:

Soft Plastic Baits Hard Baits – Topwater Hard Baits – Subsurface Jigs
Abundance in Chain:

Abundant
Fighting Quality:

Excellent Fighter

Habitat & Behavior

Spring (Pre-spawn): 8-15 feet (staging areas near spawning sites)
Spring (Spawn): 1-5 feet (shallow protected areas with hard bottom)
Spring (Post-spawn): 5-12 feet (transitioning back to summer patterns)
Summer: 8-20 feet during day; 3-10 feet during low-light feeding periods
Fall: 5-15 feet (following baitfish and feeding aggressively)
Winter: 15-25 feet (deep, slow-moving water with structure)

Spawning Season & Behavior

Primary Spawn: Late April through June (peak: mid-May) when water temperatures reach 60-75°F; optimal spawning occurs at 63-68°F; moon phases influence spawning intensity with full and new moons triggering increased activity

Spawning Habitat: Shallow protected areas 1-5 feet deep with firm bottom substrate (gravel, sand, clay, hard mud); prefer areas near deeper water for quick access; seek protection from wind and waves; backs of bays, boat channels, near docks, alongside fallen trees, edges of vegetation; males select and prepare nest sites

Reproductive Behavior: Pre-spawn (April-early May): Males move shallow first when water reaches 55-60°F; females stage in deeper water 8-15 feet near spawning areas feeding heavily; peak time for catching trophy females

Nest Building: Male selects site and fans out circular depression 2-3 feet in diameter using tail; clears debris creating clean spawning bed; nest building takes 2-5 days; males may build multiple nests; nests often in colonies with multiple bass nesting in proximity

Spawning Act: Female approaches nest when ready; male courts female with aggressive displays; female deposits 2,000-43,000 eggs (larger females produce more) in multiple clusters on nest bottom; male immediately fertilizes eggs; spawning occurs over 2-4 hours; female may spawn with multiple males or leave eggs with single male

Post-Spawn Male Behavior: Male remains on nest fanning eggs to provide oxygen and prevent fungus; guards nest aggressively from all intruders including much larger fish; attacks lures, fish, turtles, snakes, diving birds; does not feed during guard period; fans eggs for 2-4 days until hatching; continues guarding fry for additional 7-10 days; fry form tight school near nest called “fry ball”; male protects fry until they disperse; males lose significant weight during 2-3 week nest defense period

Post-Spawn Female Behavior: Females leave nest immediately after spawning; move to nearby deeper water 10-20 feet; rest and recover for 7-14 days before resuming feeding; slow bite during immediate post-spawn recovery; gradually return to normal feeding patterns

Fry Development: Eggs hatch in 2-4 days; fry remain attached to nest bottom feeding on yolk sac; become free-swimming after 5-7 days; school tightly under male protection; feed on microscopic zooplankton initially; at 1-2 inches begin eating insect larvae and small crustaceans; at 2-3 inches start eating small fish; rapid growth first year; males reach sexual maturity at 1-2 years (8-12 inches); females mature at 2-3 years (12-14 inches)

Multiple Spawn Potential: Large females may spawn 2-3 times in a season if conditions remain favorable; later spawns occur in June; fish spawning later typically smaller males and females

Conservation Status

Excellent: secure species with thriving populations throughout range and in Fox Chain O’Lakes

Management Efforts: Natural reproduction eliminates need for stocking; liberal harvest regulations (6 fish limit, 14-inch minimum) support recreational fishing while maintaining population; habitat protection emphasizing vegetation management balancing navigation needs with fish habitat; water quality monitoring and improvement initiatives; fishing access development and maintenance; creel surveys monitoring harvest and population trends; partnership with bass fishing organizations promoting catch-and-release ethic

Threats: Habitat degradation through excessive vegetation removal; shoreline development reducing spawning habitat; water quality issues (algae blooms, low oxygen); invasive species (Asian carp potential competition); climate change affecting spawning timing and success; pollution and contaminants; nest disturbance during spawning season

Protection Measures: Minimum size limit (14 inches) allows fish to spawn at least once before harvest; vegetation management policies balance access with habitat needs; shoreline buffer encouragement protecting spawning areas; water quality improvement programs (septic system upgrades, stormwater management); invasive species monitoring and control; catch-and-release education emphasizing proper fish handling; tournament best practices minimizing mortality; spawning season awareness encouraging careful handling of nesting bass

Best Practices for Anglers:

Practice catch-and-release, especially for larger bass (16+ inches) as prime spawners
Use circle hooks or crimp barbs for easier, less damaging releases
Landing nets significantly reduce fish injury and improve landing percentage
Support bass horizontally, never vertically by jaw alone (especially larger bass)
Minimize air exposure—keep fish in water as much as possible, under 30 seconds in air
Revive exhausted fish before release—support in water, moving gently forward until fish swims away strongly
During spawning season, handle nesting bass carefully and return immediately to minimize time off nest
Hot weather: extra care with catch-and-release; fish may be stressed; consider fishing early/late or avoiding extreme heat days
Remove all litter and fishing line—discarded line kills bass and wildlife
Report fish kills or pollution to IDNR
Participate in habitat improvement projects and conservation organizations
Educate others about proper fish handling and conservation ethics

Fishing Techniques

Topwater Fishing: Early morning and evening; cast to open pockets in vegetation, along weed edges, over submerged grass; walk-the-dog retrieve with stick baits; pop-and-pause with poppers; steady retrieve with buzzbaits; pause after initial splash to trigger strikes; explosive surface hits

Texas Rig/Flipping/Pitching: Target heavy cover (lily pads, fallen trees, docks, thick vegetation); use 1/4-1 oz weights based on cover density; flip or pitch to specific targets; let fall on slack line watching for line movement; set hook hard; power fish out of cover; black/blue, green pumpkin colors

Wacky Rig: Weightless stick bait (Senko-style) hooked through middle; cast to docks, weed edges, open water; let fall on slack line; twitch occasionally; extremely effective finesse technique; natural colors

Crankbait Fishing: Cast and retrieve over submerged vegetation, along drop-offs, rocky points; use deflection technique (bouncing off cover); vary retrieve speed; stop-and-go retrieve; match diving depth to target zone; shad patterns most productive

Spinnerbait Fishing: Versatile search bait covering water quickly; retrieve over submerged vegetation, along weed lines, around structure; vary retrieve speed from slow-roll to fast burn; blade flash attracts bass; white/chartreuse in stained water, natural in clear

Frog Fishing: Cast over lily pads, vegetation mats, slop; walk frog across cover; pause at openings; set hook after feeling weight (don’t set on splash); use heavy braid for pulling fish from cover; summer and fall prime periods

Drop Shot: Finesse technique for clear water or pressured fish; nose-hook soft plastic 12-18 inches above weight; subtle shaking action; effective on deep weed edges, rock piles; natural colors; excellent post-frontal technique

Carolina Rig: Deep water technique for offshore structure; drag slowly across bottom; 2-4 foot leader; creature baits or worms; feel for bites through clicking weight; let fish run before setting hook

Swimbaits: Cast and retrieve with steady swimming action; work weed edges, open water over submerged vegetation; vary retrieve depth; paddle tail creates realistic swimming motion; effective for larger bass

Jig Fishing: Versatile year-round technique; hop along bottom in cover; swim through vegetation; drag slowly across structure; pair with chunk or craw trailer; feel for subtle bites; set hook immediately

Current Regulations

Daily Limit:

6 fish per day (Illinois statewide limit) Note: Bass anglers typically practice catch-and-release; selective harvest of smaller fish (14-15 inches) if desired
Minimum Length:

14 inches (Illinois statewide) Note: Fox Chain O’Lakes follows statewide largemouth bass regulations; total length measured from nose to tail
Special Rules:

Tournament Regulations: Special permits required for organized bass tournaments; check with IDNR for current requirements; weigh-in procedures must minimize mortality

Spawning Period Ethics: While legal to fish during spawn, many anglers practice catch-and-release exclusively during nesting (late April-May) to protect reproduction; handle nesting bass carefully and return quickly

Catch-and-Release Best Practices: Use barbless hooks or crimp barbs for easier release; landing nets protect fish and increase landing success; avoid touching gills; support horizontally; minimize air exposure; revive exhausted fish before release

Size Selective Harvest: Consider releasing larger bass (over 16 inches), especially females, as prime spawners and genetic contributors; smaller bass (14-15 inches) acceptable for occasional harvest

Handling During Heat: Extra care during summer heat; keep fish in water as much as possible; avoid fishing during extreme heat if practicing catch-and-release

Live Wells and Culling: Tournament anglers must use aerated live wells; follow proper fish care procedures; quick culling to minimize stress

Photography: Quick photos preferred; support fish properly; keep in water for extended photo sessions when possible