Bass Largemouth (lat. Micropterus salmoides)
The largemouth bass is the biggest and most renowned
member of the Centrarchidae family of sunfish and its subgroup
known as black bass. It is sometimes confused with
the smallmouth in places where both species occur, and
also with the spotted bass (see: Bass, Spotted). One subspecies,
the Florida largemouth bass (see: Bass, Florida Largemouth),
M. salmoides floridanus, is capable of attaining large
sizes in appropriate waters but is otherwise similar.
OTHER NAMES:
black bass, largemouth,
bigmouth, linesides,
Oswego bass, green bass,
green trout, Florida bass,
Florida largemouth, southern
largemouth, northern
largemouth; French:
achigan à grande bouche;
German: forellenbarsch;
Italian: persico trota;
Japanese: okuchibasu;
The largemouth bass has an elongated and
robust shape compared to other members of the sunfish
family. It has a distinctively large mouth, as the end of its
maxillary (jaw) falls below or beyond the rear margin of the
eye; the dorsal fin has a deep notch separating the spiny
and soft rays; and the tail is broad and slightly forked.
Although coloration varies greatly and is especially
dependent on biological factors and host environments, the
largemouth bass generally has a light green to light brown
hue on the back and upper sides, white lower sides and
belly, and a broad stripe of diamond-shaped blotches along
the midline of the body. This stripe particularly distinguishes
it from its close relative the smallmouth bass, as does the
upper jaw, which in the smallmouth does not extend past
the eye. The largemouth lacks a tooth patch on the tongue,
which helps distinguish it from the spotted bass.
Although the largemouth bass can live up to 15
years, the average life span varies; these fish seldom live
more than 10 years. Throughout their range, largemouth
bass encountered by anglers average 1 to 11⁄2 pounds (10
to 13 inches) but are commonly caught up to 5 pounds and
less commonly from 7 to 10 pounds.
The maximum size attainable may be 25 pounds, but this
has not been proven, and only about a dozen bass in the
20-pound class are known to have been caught. The largest specimen is the all-tackle world record of 22 pounds, 4
ounces, caught from Montgomery Lake, Georgia, in 1932.
Largemouth bass spawn from late
winter to late spring; the timing depends on latitude and
temperature. Southern populations spawn earliest, and
most northern populations latest. They begin to spawn
about the time the water temperature reaches 60°F. Fish of
about 10 to 12 inches are mature enough to reproduce for
the first time. The male selects and prepares the nest site, a
circular bed usually in 1 to 4 feet of water, often positioned
near or including some type of object along the shoreline.
The female is nudged to the nest site by the male, deposits
her eggs, and leaves; the male guards the eggs, which
hatch in a few days, and then guards the young fry for a
short period.
Growth rates for largemouth bass are extremely variable,
influenced as they are by broad geographical location (north
versus south), the specific body of water they inhabit within
a particular region, and individual differences even within
the same population. Despite these influences, bass are
capable of growing quickly under the right circumstances.
Adult bass predominantly eat
other fish, including gizzard shad, threadfin shad, golden
shiners, bluegills and other sunfish, small catfish, and many
other small species, plus crayfish. They are extremely opportunistic,
however, and they may consume snakes, frogs,
salamanders, mice, and other creatures.
As aggressive predators, bass primarily are ambush feeders,
but they may pursue fish in open water, where there are
no ambush opportunities. In normally warm waters, digestion
occurs fairly quickly; however, at extremely warm or
cold temperatures digestion actually slows, causing the bass
to feed less frequently and making them less susceptible to
anglers.
Bass are well known for their ability to locate prey in
turbid water and at night. Although they are primarily sight
feeders when water clarity permits, they otherwise use
their highly developed lateral line to detect vibrations and
locate prey. They can also detect odors, but their senses of
smell and taste are poorly understood by scientists and evidently
used less for feeding than are their senses of sight or
hearing.
The largemouth
bass is endemic only
to North America, and its
native range was generally
the eastern half of the
United States and southernmost
Ontario and Quebec
in Canada. Since the late
1800s, its range has been
expanded to include major
or minor portions of every
state in the United States,
except Alaska, and most of
the southern fringes of
Canada, as well as numerous
countries in Europe,
Asia, Africa, South America,
Central America, and the
Caribbean.
The largemouth
bass is typically described as
a fish that frequents the weedy sections of ponds and
lakes. In reality, the largemouth
is highly adaptable
to many environments and
to many places within various
types of water. These
bass inhabit creeks, ditches,
sloughs, canals, and many
little potholes that have the
right cover and forage, but
they live principally in reservoirs,
lakes, ponds, and
medium to large rivers, and
not always in the weedy
sections.
More specifically, however,
they orient toward
cover and find most of their
food in or near some form of
cover. Favored haunts
include logs, stumps, lily
pads, brush, weed and
grassbeds, bushes, docks,
fencerows, standing timber,
bridge pilings, rocky shores,
boulders, points, weedline
edges, stone walls, creekbeds,
roadbeds, ledgelike
dropoffs, humps, shoals,
and islands. Although much
bass cover is nearshore,
some bass do spend time
away from shore, especially
in unvegetated lakes.
Largemouth bass are
most active in waters ranging
from 65° to 85°F; the
lower 70s is likely optimum.
Yet they do well in temperatures
much higher and
lower, including waters that
touch the 90°F mark, as
well as frozen lakes that dip
to the mid-30s.