Largemouth Bass -- Micropterus salmoides  



History:  Largemouth bass were originally established from eastern Canada, through the Great Lakes drainage, south to Mexico and from Maryland to Florida along the East coast. They have been widely introduced into Oregon.


Bass fry


Physiology:  Largemouth bass are members of the Centrarchidae Family and can be distinguished from other bass by the intense, black lateral band along the side (particularly in young fish), the maxilla extending well beyond the posterior edge of the eye in adults, and dorsal fin almost divided with spines of unequal length.  They are dark greenish in color; adults have a very dark, irregular lateral band. Bass eat small fish (including other bass), insects, larvae, crayfish, tadpoles, worms, frogs, salamanders, lamprey ammocoetes, mice and small birds.  It is difficult to train bass to accept artificial foods--thus, their productivity is limited to their natural environment.  Life expectancy of largemouth bass is ten to thirteen years, but some live up to sixteen years.

Habitat:  Non-turbid, highly fertile, non-flowing water stocked with forage fish are ideal ponds for bass.  Ideal pond depth is 5-7', stable pond levels with gravel along banks and moderate weed growth.

Optimum growth is attained at 80 F; at 50 F, bass become inactive.  Salinity exceeding 5,000 ppm is unsuitable for bass.  pH range must be 6-9.5.  Bass do not grow well in muddy ponds because they feed by sight.  Water clarity should be at least 8" and preferably 12" for feeding. 

Reproduction:  Bass may spawn the lst year following stocking if water temperature, food supply and other conditions foster optimum growth (7-10" in length). 

Bass spawn late May to early June when surface water temperature approaches 70 F mid-day.   Females may spawn 1-5 times during the 6-8 week spawning season, with the first spawn being the biggest in terms of number of eggs released. 

Ken and Luke with largemouth bass.


The number of fry produced per spawn varies from 5,000-25,000.  Bass prefer solid, silt-free substrates, which can include gravel, firm mat of roots, submerged stumps, logs, etc.  Artificial spawning sites can include spawning boxes (2'x2'x2' containing 1 1/2" minus round rock).

The male bass selects a nest site, normally in 1-4' of water depth near the shore.  A shallow, circular nest is constructed by sweeping away debris to about twice the male's body length.  Males typically guard an area about 6' surrounding the nest site.

When a ripe female joins the male, they slowly circle the nest, side by side, in a tilted fashion so their vents are close.  Both fish shudder as eggs and sperm are released simultaneously.

Males guard the nest until the eggs hatch (2-4 days) depending on water temperature.  Success is sharply reduced if temperature drops below 60 F.  Fry swim up off the nest after several days after hatching and begin feeding on zooplankton, along with close protection from the adult male.  They disperse three to ten days later after circling the pond in an "anchovy-like" fashion. 

Growth:  Assuming optimum water temperatures and adequate food supply, fry reach 1.5-2" within 2-4 weeks.  Within 40-60 days, bass reach 3-4" in length.  Bass regularly reach 2 lbs, and may grow to 10 lbs in Oregon.

Bass begin to eat fish when they are about 2" in length.  They swallow live fish and other organisms whole rather than biting off chunks.  Thus, what they can eat is limited by the size of the food.


Maximum Growth Rates:

Years After Socking













5 oz.

10 oz.

15 oz.

20 oz.

24 oz.


Frequently Asked Questions: Be sure to remove forage species (such as bluegill or crappie)at the same rate as stocking.  Basically, remove large bass and approximately three bluegill or crappie per bass.  If you remove the large fish, you will make it possible for the smaller fish to grow in your pond for fishing in future years.

How can I manage my bass pond for maximum bass production?
To optimize production in your pond, remove (and eat) bass at about 12"+  in length. The will allow the smaller bass to grow and replenish your pond. To optimize enjoyment of your pond, catch and release a few "whopper" bass. It's great fun knowing that this time you might catch "The Big One".

What are Florida-strain largemouth bass?
Florida bass grow larger at about 60 F and will freeze and die at lower temperatures. Northern largemouths continue to grow at temperatures into the 50's. At low water temperatures, Northern largemouths hibernate and absorb oxygen statically--that is without moving their gills.

What about smallmouth bass?
Smallmouth bass favor cooler, deep lakes and rivers with rocky substrates. They like to hang-out in tree roots and blow-down tangles of tree limbs. Smallmouth bass can be distinguished from largemouth bass by comparing their jaws, which in smallmouth bass extends to the center of the eye (whereas the jaw in largemouth bass extends beyond the eye). Eyes in the smallmouth bass are carmine red.

Luke, a bit older, holding a largemouth bass.