Largemouth Bass Research
Here you can find research articles dedicated to Florida's favorite freshwater sportfish, the largemouth bass.
Researchers experiment with new hatchery procedures to better prepare young largemouth bass for the perils of the wild.
As Florida's premier freshwater sport fish, the largemouth bass is the central figure in a black bass fishery that generates more than $1.25 billion annually for the state. Maintaining and improving this valuable resource is a continuing effort that relies in part on supplementing wild stocks with hatchery-raised bass.
The FWC's Fish and Wildlife Research Institute (FWRI) evaluates these stocking programs and researches ways to improve them. In recent studies, biologists from FWRI's Eustis Fisheries Research Laboratory collaborated with researchers at the Florida Bass Conservation Center, the FWC's fish hatchery in Webster, to address some of the challenges of introducing hatchery-raised young bass into the wild.
Researchers have found that stocked bass have difficulty adjusting from feed pellets at the hatchery to live prey in the wild. They also typically lack the predator avoidance and survival skills of wild fish.
Biologists documented this vulnerability in a study at Lake Carlton in the Harris Chain of Lakes (Lake County). They tracked young hatchery bass and wild bass with radio telemetry to compare their behaviors. The researchers found that hatchery bass tended to wander away from cover more often than wild bass. Failure to avoid predators, including birds, was apparent from the radio tags that turned up on shore under nests, in neighboring Lake Beauclair, and even inside a live double-crested cormorant. Findings also showed that neither wild nor hatchery bass showed a preference for specific vegetation for cover.
Now researchers are adding predators and live prey to hatchery ponds, conditioning young bass to forage and avoid predators before entering the wild. Early results from this study have been encouraging. Conditioned fish tend to outgrow and survive other hatchery bass, indicating both improved foraging and avoidance of predators.
Additional research is under way to evaluate other aspects of the hatchery and stocking process and ensure that survival rates for stocked bass continue to improve, keeping the largemouth bass abundant for Floridians and visiting anglers.
Reward tag studies are one method biologists with the Fish and Wildlife Research Institute (FWRI) use to learn about Florida’s freshwater fish populations. These studies also engage anglers in the scientific process, helping connect researchers and managers to the stakeholders they serve and validate the science on which management decisions are based.
Most tagging studies consist of a few basic components. Scientists first collect and tag fish in a particular lake or region. They then release the tagged fish back into the population. Each tag has a phone number on it, allowing anglers who catch a tagged fish to report information about their catch to biologists. Each tag also has a monetary reward associated with it to encourage angler reporting.
Biologists primarily use tagging studies to estimate annual catch and harvest rates for fish populations to help managers set regulations that sustain healthy bass populations. FWRI biologists are conducting three largemouth bass tagging studies that range in scope from a trophy-sized bass study encompassing the entire state to a study targeting bass in a single lake.
Northwest regional tagging study
FWRI biologists are conducting a reward-based tagging study in Northwest Florida, west of the Suwannee River. In late 2012, they tagged bass 12 inches and longer in 16 lakes across the 12-county study area. Biologists are monitoring tag returns for one year to measure catch and harvest rates. The data they provide to managers will be discussed with anglers to help determine the most suitable regulations for creating and sustaining quality bass fisheries in this region.
Lake Eustis tagging study
Lake Eustis is part of Central Florida’s Harris Chain of Lakes, a popular bass-fishing destination. The primary objective of this study is to complete a full stock assessment of the largemouth bass population in a moderately to heavily fished lake. Biologists will use data from tag reports to estimate the percentage of bass caught and harvested each year. They will combine this information with other data and provide it to managers, who can then determine if the current length and bag limits are appropriate or need to be adjusted. As a secondary objective, biologists are using what they learn from the tag returns, along with data from creel surveys and other information, to determine the best way to estimate the total number of bass in a large lake.
What to do if you catch a tagged largemouth bass
FWRI biologists use the same yellow plastic dart tags for all bass tagging projects. These thin, 3.5-inch-long tags are attached to the bass on the left side near the dorsal fin. If you catch a tagged bass, clip the tag close to the fish’s back and save the tag. Anglers are not obligated to release tagged bass but must comply with harvest regulations. When you report the tag, an FWRI staff member will ask a few brief questions about your catch and help you claim the monetary reward. Anglers, remember to check each bass you catch, sometimes algae covers the tag making it somewhat difficult to see, so look closely. Tagging studies give you the opportunity to participate in valuable research that helps managers sustain Florida’s largemouth bass fisheries.
Note: If the phone number on the tag is not legible, call the appropriate number listed below.
- Northwest regional study: 850-717-8736
- All other bass tagging studies: 850-363-6037
Stocking of Hatchery-Reared Largemouth Bass in Lake Talquin (2022-2024)
- Freshwater Fisheries biologists stocked 274,300 largemouth bass into Lake Talquin in May of 2022.
- This is part of a 3-year effort to enhance Talquin's largemouth bass population.
- FWC plans to stock more than 800,000 largemouth bass into Lake Talquin by the end of 2024.
Lake Talquin (25 miles west of Tallahassee) is an 8,800-acre reservoir formed in the late 1920s by damming the Ochlockonee River. This productive reservoir has an abundant supply of shad (critical largemouth bass prey). However, Lake Talquin is deeper than most Florida waters and does not support the extensive aquatic vegetation that is important to early bass survival and recruitment. As a result, most year classes of bass are marginal to poor except following extreme, habitat producing drawdowns of the reservoir. Largemouth bass usually do not spawn until late March or April in Lake Talquin, which is often too late to take advantage of the abundant shad produced in April and May. Shad spawned in the spring quickly outgrow young native bass because of slower bass growth.
To evaluate any stocking program, biologists must be able to identify hatchery fish. Researchers can do this through genetic parentage analysis, comparing tissues samples from largemouth bass collected during their sampling efforts to the genetic make-up of the brood stock largemouth bass used at the hatchery. In May 2022, approximately 274,300 (1.5 - 3 inches) largemouth bass were stocked into Lake Talquin. By December of 2022, the stocked largemouth bass made up an estimated 10% of the 2022 year-class. These preliminary results suggest far-less contribution to the year-class than previous stockings in the early 2000’s. Hatchery contributions ranged from 17-40% of individual year-classes from 2000-2003. An additional 442,800 largemouth bass were stocked into Lake Talquin in May of 2023 and a preliminary assessment of that stocking is slated to begin in late fall of 2023. Most of these individuals were (1.5 - 3 inches) and the success of this stocking will be determined later this year. The final year (2024) of this 3-year stocking effort is aimed to produce and stock fewer bass, but of a larger-size (3 inches or greater) at the time of stocking in hopes of increased survival.
In summary, FWC plans to stock more than 800,000 into Lake Talquin from 2022 to 2024. Success of these efforts will be determined in years to come through electrofishing surveys and monitoring catches in Lake Talquin’s largemouth bass tournaments. Researchers hope to replicate previous successes to help make Lake Talquin a premier destination for trophy largemouth bass in Florida once again.
FWRI researchers have completed a four-year study looking at the consequences of bed fishing.
- The first two years were completed in hatchery ponds at the Florida Bass Conservation Center.
- The Last two years were completed in small natural lakes in Ocala National Forest.
- Bass were tracked genetically and each nest was marked and observed.
- Nests were fished and caught bass were safely stored away for 60 minutes before being returned.
- The results show that bed fishing does not significantly impact the numbers of young bass entering the next generation.
- 30% of all wild beds succeeded whether they are fished or not.
Over the last four years, Florida Fish and Wildlife Conservation Commission (FWC) biologists studied the effects of bed fishing on Florida’s largemouth bass populations. This topic has been stressed by the angling community, and freshwater fisheries researchers were more than happy to tackle this hot-button issue.
Bed fishing is the practice of fishing bass nests in the spring. Nests can typically be seen from the surface as cleared patches near structure. Male bass instinctively defend their nests, giving anglers a higher chance of fishing success. However, while the adults are off the nest, predators such as bluegill and other panfish eat the eggs and bass hatchlings. The debate over this fishing tactic is whether or not this time taken away from the nest, sometimes hours in tournament conditions, is negatively effecting Florida’s bass populations.
The study began at the Florida Bass Conservation Center near Webster, FL. Each mature bass received a tag and fin clipping for identification and tracking their parental contribution using genetic analysis. In preparation for the bass, hatchery staff placed brush and concrete blocks in the ponds for added spawning habitat along with a stocked fish community to provide food for the bass and nest predators and to simulate a natural water body as best as possible. After the fish were acclimated to the controlled hatchery ponds, biologist performed snorkel surveys to count, mark and track the bass beds. After beds were located, biologists collected five to ten eggs from each active nest for DNA analysis. Using the DNA data from eggs on a nest, biologists tracked how many times each individual male and female bass spawned throughout the spring.
Half of the ponds were fished and caught bass were removed from the nesting area for one hour to observe the impact. After that hour the fish were returned to the pond safely. The other half of the ponds were never fished and only observed on schedule. In the fall, the ponds were drained and all the fish collected. Using genetic analysis of fin clips taken from all young bass documented during the year and comparing it to the known adult bass in the pond, biologists identified which mature males and females contributed to the year class produced. With the angling data, biologists also determined if fish that were caught during the study successfully contributed young bass or see if it was only fish that were not caught that contributed.
This study was repeated with slight alternations in small natural lakes in the Ocala National Forest over the next two years to look specifically at individual nest success rates in the wild.
After four years of research, biologists found that bed fishing has very little impact on how successful individual nests are or the numbers of next generation of bass produced. Fished or unfished, only 30% of all wild bass beds succeeded in this study. The only effect bed fishing had was under high fishing pressure. Under high angling pressure fish may not spawn as many times as unfished populations, but this result was only seen in the relatively small (one acre) hatchery ponds. The number of young bass produced was still unaffected and even bass caught multiple times went on to contribute as much as fish that were never caught. FWC freshwater fisheries researchers would like to thank the many anglers who have requested this study. FWC works for you as much as they work for Florida’s fish and waterways.
TrophyCatch transforms and activates the angling community into becoming “Champions of Conservation” by having anglers photo-document and submit pictures of their largemouth bass catches that weigh eight pounds or heavier to TrophyCatch. This catch-and-release program rewards anglers for their catches by placing them into a prizing category based on the weight of the fish.
The benefits of participating in TrophyCatch include collecting valid citizen-science information about trophy bass to help the FWC better enhance, conserve and promote trophy bass fishing.
FWC freshwater researchers use photo analytics to assess TrophyCatch submissions.
- TrophyCatch made submissions easier in season two.
- While easier on fish and anglers, it left biologists with less data.
- Biologists developed a way to estimate fish size just from pictures.
- As the technique becomes more refined and accurate, biologists will use it more as a tool for the program.
Trophy bass photo analytics relies on an object of known dimensions (A) to make measurements of a bass’s length (B), body depth (C), or cross-sectional area (D).
FWC researchers tested and verified the accuracy of the trophy bass photo analytics tool under “real-world” circumstances encountered by TrophyCatch.
TrophyCatch relies on photo documentation of a bass’s weight for program qualification. Originally, the program required participants to photo document both weight and length of entrant bass to qualify for Lunker and Trophy levels, and Hall of Fame level bass required on-site verification by a Florida Fish and Wildlife Conservation Commission (FWC) biologist. Season two of the program transitioned to requiring only a single weight-documentation photograph for all three tiers of recognition to simplify the process. This shift reduced handling of bass, reduced their time out of water, and made it easier for anglers to participate. However, by lifting the requirement of length-documentation photos it left TrophyCatch biologists with less information to help verify reported weights of entrant bass.
Researchers begin investigating alternative methods of verifying length of and weight of trophy bass. They developed a technique referred to as “trophy bass photo analytics” where biologists use an object of known size in the photo (e.g., measuring tape or digital scale) to scale dimensions within the focus of the photo, which can then be applied elsewhere in the shot. Similar to existing equations that use length and girth to estimate a bass’s weight, trophy bass photo analytics allows biologists to measure a bass’s length, body depth, or cross-sectional area in a photo, and these values can then be entered into equations that estimate a bass’s weight.
FWC’s trophy bass photo analytics equations are based on nearly 200 bass that were photographed, weighed, and measured by biologists during 2014–2015. To make sure that these methods were applicable to bass of nearly all sizes, they included bass from 2.2–13.1 lbs; however, 65% of the bass were ≥ 8 lbs, since the project’s focus was to help verify weights of trophy bass.
Although the core process of trophy bass photo analytics has been the same throughout development, researchers have continuously honed and diversified the technique. It can be applied to variety of bass orientations, such as vertically or horizontally held bass or bass lying on a flat surface. As testing and refinement of these techniques verify accuracy standards, TrophyCatch biologists expect to increasingly rely on trophy bass photo analytics as a tool for the program.
FWRI biologists try to crack the riddle of Kingsley Lake
- FWC has made trophy Largemouth Bass management a priority in FWC’s Black Bass Management Plan.
- The TrophyCatch program helps biologists collect data on hard to study trophy-size largemouth bass.
- Kingsley Lake is home to a disproportionate number of trophy bass documented in the program.
- Biologists theorize the deep cooler waters of Kingsley provide a summer refuge for bass, slowing metabolism and reducing stress.
- Researchers are currently conducting a study tracking these large bass while logging water temperatures and depth.
Trophy-size fish are a critical component of Florida’s world-renowned bass fisheries. Big Florida bass are part of the identity of our freshwater fisheries and the chance to catch one draws anglers from near and far. To underscore their importance the Florida Fish and Wildlife Conservation Commission (FWC) has made trophy Largemouth Bass management a priority in FWC’s Black Bass Management Plan (BBMP) and launched TrophyCatch, Florida’s trophy bass conservation program. TrophyCatch serves as both an angler recognition program and a crowd-sourced data collection mechanism for trophy bass in Florida. These fish are relatively rare and infrequently collected by the FWC.
As data grew biologists noticed that Kingsley Lake was home to a disproportionate number of trophy bass documented in the program and four of the top five heaviest bass documented in TrophyCatch have come from this old, north-Florida lake. This led researchers to the question—what is going on at Kingsley Lake?
Big bass aside, Kingsley Lake stands out among typical Florida lakes due to its depth. Previous reports indicated depths up to nearly 80 feet, which were confirmed with our sonar (82 feet max depth). Interestingly, upwards of 300 acres of the interior of the lake, is ≥40 feet deep. This provides stark contrast to most Florida lakes, where “deep” is around 10–15 feet.
One theory as to why Kingsley Lake grows such big bass is that its depth provides cool sanctuary for bass during Florida’s warmest months. Water density changes with temperature, with warmer water floating on top of cooler water. Often this results in layering (thermal stratification) of water in lakes in summer. Because bass are cold-blooded, they are always the same temperature as their surrounding water, and their metabolism is governed largely by temperature. Florida bass thrive in warm waters, but summer temperatures put their metabolism in high gear, where they burn through calories, somewhat reducing the energy available for packing on body mass. Having access to deeper, cooler water in lakes like Kingsley might allow bass to maintain metabolic rates closer to optimum during summer. It may also reduce their natural mortality rate by reducing some of the stress that bass endure after spawning, as water temps quickly rise. Possibly, Kingsley bass enjoy a combination of both of these factors. Biologists do know that some bass in Kingsley Lake have reached an absurdly old age for bass in Florida with researchers recently ageing two bass that died of natural causes that were a few months shy of 16 years of age. This gives some credence to the thought that Kingsley bass attain such large sizes, simply by living much longer than the average bass in Florida.
To find out what is going on biologists designed a temperature and depth selection study. They implanted 10 bass with acoustic telemetry tags equipped with depth and temperature sensors. The tags continuously emit ultra-sonic signals that contain the depth and temperature measurements for where the bass is located. Researchers hear and decode the tag signals with underwater receivers that temporarily store these data. They also made a detailed bathymetric map of Kingsley Lake and have temperature loggers deployed across a range of depths. Later biologists can compare the depths and water temperatures used by our tagged bass with the depths and water temperatures available to them in the lake. Researchers also designed the receiver array to provide 100% coverage of the lake, meaning they should continuously hear the fish for the duration of the project as long as they remain in the lake. Study bass were tagged during December 2015–January 2016, and the operational life of the tags is about 24 months. The study is expected to last at least those two years.
In the end biologists hope to better understand the conditions that drive exceptional trophy-bass fisheries, like Kingsley Lake. If they are able to identify critical depth or temperature preferences of bass at Kingsley Lake, they could use that knowledge to identify other lakes in Florida that have similar characteristics with the possibility of implementing fisheries management actions such as stocking, boat ramp access and construction, or fish attractor construction at these lakes.
FWRI biologists discuss the factors that contribute to the growth of trophy-sized Florida largemouth bass.
Anglers from around the world travel to Florida for the opportunity to catch a Florida largemouth bass (Micropterus salmoides floridanus). The state is known as the Fishing Capital of the World in part because of the trophy-size largemouth bass that can be found in many different habitats, from one-acre ponds to large natural lakes, rivers and marshes. In general, trophy-size Florida bass grow faster than the general population. However, not all bass reach trophy status. Actually, chances are slim that any bass will grow to 8 pounds or larger. Trophy-size fish are typically the old and rare members of the bass population and many things must fall into place for them to reach this size. Decades of research on the Florida bass have revealed several about these sought-after sportfish.
The most important factor influencing the occurrence of trophy-size bass is natural growth potential. Florida bass are genetically different and grow much larger than the northern largemouth bass. Scientists at the FWC’s Fish and Wildlife Research Institute (FWRI) have surveyed lakes and rivers across Florida to determine where genetically pure Florida bass populations occur. The FWC has established conservation programs to protect these populations.
Growth to trophy size also differs between genders. Female Florida bass grow faster than male bass and typically only the females grow larger than 8 pounds. Florida’s warm climate and long growing season also enhance the growth rates of largemouth bass.
Even with faster growth rates, it takes a while for Florida largemouth bass to reach its full potential, so survival is always a factor in becoming a trophy bass. The recorded ages of trophy-size bass have ranged from 4-16 years old, with an average of 10 years of age in Florida. But only a small percentage of largemouth bass live longer than 5 or 6 years, so reaching 10 years of age and trophy size is not the norm. Many factors can affect a bass’s odds of surviving long enough to reach trophy-size.
- Year One: During its first year of life, bass must not only find enough to eat, but also avoid being eaten by predators. Most fish do not make it through the first year.
- Anglers: Bass that survive the juvenile stages then have to avoid being caught and harvested by anglers. High rates of harvest, particularly for larger bass, lower the probability that fish will grow to trophy sizes. Slot size limits tend to allow more Florida bass to reach trophy sizes.
- Stress: For bass fortunate enough to find enough to eat, avoid predators and not be harvested, there are still threats to their survival. Stressors, such as low dissolved oxygen, can weaken their resistances to disease and infection leading to natural deaths. All things considered, it is pretty difficult for a bass to survive long enough to reach trophy size.
When it comes to how food is related to bass growth, there is more to it than just the amount of prey available. The size and location of the prey affect a bass’s ability to capture them. Also, the energy required to catch prey, caloric content of the prey, digestion rates, and the rate the fish burns the energy all influence bass growth rates. Diet studies demonstrate that big bass eat large prey items, so availability of prey such as large-sized chubsuckers, shads, sunfish, and tilapia may have an effect on the size a bass can attain.
Habitat conditions also play a significant role in the production of trophy-size bass. Like plants, bass thrive in nutrient-rich environments. Water bodies that are naturally high in nutrients or have been enriched by human activities (e.g. agricultural runoff or phosphate strip mining) are more likely to produce trophy bass.
Clear lakes with good water quality and abundant aquatic plants also produce good numbers of trophy-size bass. For small bass, an abundance of aquatic vegetation provides cover from predators and supports a wide variety of prey like insects, crayfish and small fishes. In fact, the majority of bass reported to the FWC’s Big Catch Program the last 20 years were caught in lakes with heavy growth of aquatic plants.
Extreme water fluctuations also create habitats that produces trophy bass fisheries. Sometimes this happens naturally during cycles of droughts and other times it results from lake water levels (lake drawdowns). The flooding or reflooding of a reservoir produces the same results.
The journey to trophy size is an arduous one. As research continues, biologists will learn more about trophy-size bass and the factors that contribute to their growth. Science-based conservation will aid the preservation of Florida’s bass populations, helping ensure anglers continue to have opportunities to catch this prized sport fish.
Biologists study the trophy-bass fishery in Florida
- Researchers have tagged bass ≥ 8 lbs with high-reward ($100) tags across the state since 2011.
- Information from each tag return is used to measure annual state-wide catch, exploitation, and release rates of trophy-size bass as well as measure awareness and participation rates of TrophyCatch.
- Through five years of the tagging study, FWC researchers have tagged 836 trophy-size bass (136–195 per year) from 115 public waterbodies (42–56 per year) within Florida.
Since 2011, biologists from multiple divisions of FWC have worked to tag every bass 8 pounds or heavier that they sample during annual electrofishing surveys, which allows live-release of the bass. Each year, they have tagged between 136–195 trophy bass, and to date, the project has reached more than 115 public water bodies across Florida. The tags bear a unique ID code, a FWC telephone number, and a $100 reward for reporting catch of a tagged bass.
Trophy Bass Statistics
- About one in eight to one in four trophy bass were caught by anglers in the state each year. This range of catch rates for trophy bass is quite similar to catch rates for smaller or average-size bass in Florida, suggesting that trophy bass are no more elusive to being caught than smaller bass.
- Just two to five percent of the trophy bass population are harvested each year. The tagging study confirmed the low harvest numbers by revealing 77 to 91 percent of tagged bass that were caught were released. These results reiterate that in Florida the catch-and-release ethic among bass fishermen is strong, especially when it comes to trophy bass.
- Anglers consistently caught more tagged bass via artificial lures (74–92%) than on live bait (8–26%). Interestingly, that pattern was mirrored by TrophyCatch data.
- This doesn’t necessarily mean that artificial lures are better than live bait at catching big bass. To identify which is more effective, researchers would also need to know how frequently lures (or live bait) are used across all bass fishing trips, regardless of whether a trophy bass was caught. Future angler surveys may help look into this.
- More tagged bass were caught by anglers during general recreational fishing trips (75–85%), whereas 15 to 25 percent of the tagged bass were caught during tournaments each year. As most tournament anglers would argue, they are probably not less effective at catching trophy bass. Rather, tournament fishing trips represent a small fraction of overall bass fishing at the state-wide level.
Since the trophy bass tagging study was designed to measure aspects of TrophyCatch performance and effects, researchers hope to operate the study in tandem with TrophyCatch, together monitoring Florida’s trophy bass fisheries over the long term. To register and get familiar with the submission procedures for TrophyCatch, please check out the website today. It’s a great way to get involved in science and conservation for trophy bass in Florida. If you happen to catch a tagged bass, clip the tag close to the bass’s body and retain the external end for record keeping. It has a unique identification code and telephone number (850-363-6037) for reporting your catch and collecting the tag-return reward.
Trophy Bass Tagging Study
FWC biologists are busy collecting data on trophy-sized largemouth bass in Florida lakes. In addition to the data our scientists collect, much of what we learn about these big bass come from Florida's recreational anglers who participate in the TrophyCatch Program. TrophyCatch serves as both an angler recognition program and a crowd-sourced data collection mechanism for trophy bass in Florida. Our new video highlights the work FWC biologists and other stakeholders are doing to study and manage trophy-sized largemouth bass in Florida.