Species Profile - Large Mouth Bass

Largemouth bass

In Minnesota, largemouth bass can be found in shallow, fertile, lakes and river backwaters with ample aquatic vegetation as well as in vegetated bays of larger lakes. Other common names for largemouth bass are black bass, green bass, green trout, and slough bass. They are the largest species of the Sunfish family.

Identification

Largemouth bass have a two-part connected dorsal fin like other sunfish – spiny in front and soft in the back. Their bodies are generally shaped like a laterally flattened football. Their colors include a dark-green back with a white to grayish white belly and a dark black lateral stripe ranging from the gill plate to the tail. Their forward-facing mouths are very large and when the mouth is closed the lower jaw extends behind the eyes.

Food

Immature Micropterus salmoides feed on zooplankton and aquatic insects. As they grow their diet shifts to crayfish and other fish species. Sunfish are the food of choice for most adult largemouth bass.

Habitat

When handling a largemouth bass, smooth down the spines of the dorsal fin from nose to tail much like you would handle a sunfish. Lesson 6:1 – Safety and Fishing at the Water’s Edge gives a good overview on handling fish.

Reproduction

Males begin to build nests in May and June, once water temperatures reach 60°F. The nests are built in 2-8 feet of water usually on a firm lakebottom among aquatic plants for cover. After a short courtship, females deposit 2,000-6,000 eggs in the nests, which are fertilized by the males. Females generally choose the nests of the largest males, but sometimes a small male will swim in quickly to attempt fertilization of the deposited eggs and then retreat, leaving the larger male to care for the eggs afterwards. 

The males guard the nests and fan the eggs until they hatch; which takes approximately 3-4 days. Then the male will protect the fry, called a brood swarm, until they disperse after about a month. Females reach sexual maturity at about 4-5 years in age, while males reach sexual maturity around 3-4 years in age.

Largemouth bass live on average up to 15 years in the wild and 6 years in captivity. The longest known life-span of a largemouth bass in the wild is 23 years and in captivity is 11 years.

Predators

Larval and juvenile largemouth bass are prey species of yellow perch, walleye, northern pike, and muskellunge. As adults, largemouth bass can usually escape most predators. The primary predators on adult largemouth bass are humans.

Tackle

A good bass rod should have a heavy strong butt, and sensitive tips. You need a strong rod for setting the hook and reeling in the fish out of heavy cover. Probably most importantly though is to make sure you balance the rod with the same type of reel; a lightweight rod does not balance well with a heavy reel.

Anglers use artificial baits that mimic live baits and are made to pull through aquatic plants without too much snagging. Some artificial bats that are widely used are spinnerbaits, crankbaits, surface lures, jigs, and spoons. Lesson 5:4 Tackling Your Tackle Box gives an overview of the different types of lures listed here along with photos. Live bait such as night crawlers, frogs, crayfish, minnows, and leeches are popular for fishing largemouth bass. In very clear water the live bait will be a lot more effective than anything artificial

Shorefishing for largemouth bass with your students can be successful if you look for a pier or shoreline surrounded by aquatic vegetation such as rushes, lily pads, and submerged aquatic plants. Generally largemouth bass will be found among other sunfish such as bluegill and pumpkinseeds. A piece of worm rigged underneath a bobber will give your students plenty of action.

Preparation for Cooking

Filleting a largemouth bass is very similar to filleting a sunfish. Follow the step-by-step instructions provided in Lesson 6:5 – Eating Fish to clean your catch and cook up some tasty treats.

Fun Facts

• It takes about 4 pounds of food to produce every pound of largemouth bass. 
• This fish is a popular sport fish because it aggressively attacks lures and leaps out of the water when hooked.