LARGEMOUTH BASS
Micropterus salmoides

Description
The color of the largemouth bass is usually dark green on the back becoming lighter green on the sides. Generally, there is a broad continuous stripe on the mid-side which may become indistinct in large adults and individuals from turbid waters. Environmental differences, especially water clarity, exert an influence on bass coloration. The largemouth most closely resembles the spotted bass in color but does not have the series of prominent, horizontal streaks along the lower sides that are characteristic of the spotted bass.
The largemouth bass, spotted bass, and smallmouth bass are sometimes misidentified. With the largemouth bass the upper jaw (mouth closed) reaches far beyond the rear margin of the eye; the end of the upper jaw reaches to or slightly beyond the rear margin of the eye in the spotted bass; in the smallmouth bass the end of the upper jaw extends to about the center of the eye.
The spinous and soft parts of the dorsal fin are almost completely separated by a deep notch in the largemouth. These parts of the dorsal fin are broadly connected with only a shallow notch between them in the other 2 basses.
Reproduction
Like other sunfishes the largemouth bass is a nest builder. Nest building and spawning activites commence in May orJune when water temperatures run from 63° to 68° F. Rocky or gravelly bottoms are preferred for nest construction, but almost any type of bottom may be used as long as a firm silt-free bed can be created. Sometimes eggs are deposited on plant rootlets or leaves of submerged vegetation with little nest preparation. Nest depth may vary from a foot to 15 feet but is generally from 18 inches to 3 feet. As a rule, the nests are constructed in sheltered lake bays or quiet-water areas in streams. The male fans out a depression of 2 to 3 feet in diameter. As the ripe female deposits eggs, the male ejects milt for fertilization. The eggs hatch in 3 to 6 days and the fry rise from the nest and begin to feed on tiny plants and animals 5 to 8 days later. A sudden drop in water temperature of only 10° to 12°F is sufficient to kill the eggs or newly hatched fry. A light deposit of silt on the eggs after heavy rainfalls may cause the male to desert the nest.
In Illinois, the largemouth usually reaches sexual maturity as a two-year-old at a length of 9 to 10 inches, although there have been instances of spawning by yearlings displaying exceptionally rapid growth.
Food Habits
The largemouth bass feeds on a variety of animal life. The young fish feed on very small animal life such as crustaceans, insect larvae and fish fry. Fish and crayfish are extremely important food items. The largemouth is the top predator in most ponds.
Growth Rates
Growth of the largemouth bass is extremely variable, depending on the pond conditions. In Illinois, the average life span is about 4 years. Few survive more than 8 or 10 years. In southern states, because of the longer growing season, the largemouth has been known to attain 22 pounds.
Average Length and Weight by Age for Largemouth Bass in Illinois |
||||||||||
Age in Years |
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9 |
10 |
Length in Inches |
6.3 |
9.0 |
11.6 |
13.5 |
15.8 |
17.4 |
18.9 |
19.8 |
20.3 |
20.7 |
Weight in Pounds |
0.1 |
0.4 |
0.8 |
1.1 |
2.0 |
2.5 |
3.0 |
4.0 |
5.0 |
5.5 |

Fishing for Largemouth Bass in Illinois
Largemouth bass are sight feeders. After hatching, the bass fry feed largely upon tiny crustaceans called Cladocerans and Copepods. The primary food items of fingerling and adult bass are: insects, crayfish, frogs, and other fish, especially the gizzard shad. Young bass frequently school-up to feed but once they reach a size larger than a pound, they appear to be more solitary in nature.
Largemouth bass fishing is generally best from early April to mid-June and again from early September to mid-October when the water temperature ranges between 55 and 75 degrees. The best spots to fish in the spring or fall are shorelines, rock riprap or shallow, brushy or weedy areas that are utilized either for spawning or protective cover.
When daytime summer water temperatures approach the 80° mark, bass generally move to the deeper, cooler water along steep banks, in river and creek channels or old pond beds and spring seeps that also have protective cover. Plastic worms, spinner baits and the deep diving plugs are the best baits to use under these conditions. However, they will move from these areas into the shoreline shallows to feed during the early morning or late evening hours, which are prime times to fish. During the winter, largemouth bass can also be caught by using the ice fishing methods described briefly under crappie and bluegill.
Although it is impossible to describe all the ways to take bass (many books and magazine articles have been written on this subject), a few may be pointed out to hopefully increase your success. It is difficult to catch largemouth bass consistently, but they can be caught on a greater variety of baits and lures than practically any other fish. Casting with bait, spincast or spinning tackle is probably the most popular method of catching "Mr. Bigmouth".
During the spring, when most lakes have periods of murkiness, the single or tandem spinner baits, wobbling and flashing spoons with pork rinds, spinning lures and light colored sub-surface lures are the best artificials to use. Live bait fishermen use a 3 to 6 inch minnow or a fat nightcrawler with a cane or fiberglass pole, and only fish the stickups when the lake is murky.
In the summer, especially during the heat of the day, diving or deep running plugs and plastic worms are usually the most productive. If the water is clear, top water plunker, buzzer, crawler or diving baits fished along shoreline cover early in the morning or late in the evening, frequently yield limit catches. When bass are feeding on shad schools, any surface or sub-surface lure that imitates a crippled minnow is very effective. This is also the time to use a fly rod with large poppers, streamers, wet flies or hair bug lures. Other summertime fishermen use stout fiberglass poles with 25 to 50 pound test line and a weighted plastic worm, large jigs or shiners to take bass from their cool shady hideouts.
During the cooler fall months, largemouth bass generally feed from mid-morning to mid-afternoon. Again depending on water turbidity and temperatures, type of cover or time of day, one can frequently use any lure in the tackle box to catch a mess of bass.
The fisherman, who likes to use live bait such as crayfish, nightcrawlers or minnows, can frequently catch more bass than the man using a $75 rod and reel and the large boxes of artificial lures. These natural baits are usually fished around and over hanging banks, submerged brush, logs, stumps or on hard mud and sand bottoms. At other times, live baits are more effective if they are worked slowly over the bottom, or drifted with the wind or current into pockets, holes and riffles, or jigged over good cover.
Because of their temperamental moods, diverse habits and tendency to move from one area to another, catching bass can be a frustrating, mind boggling situation. To become a good bass fisherman, one must learn to be patient, adaptable and determined to be successful. Probably the best advice to give a budding bass fisherman is to learn all about the bass' habits and habitats, fish as frequently as possible, and go with someone who has developed a degree of expertise in catching this species.



