The latest research from the 2000 Black Bass Symposium.

Nesting largemouth showed a strong preference for simple, woody cover—an isolated stump, sunken tree, or single log. Although many bass nested near complex brush cover, they did so because it was abundant, not because it was preferred. Indeed, complex woody cover attracts brood predators—making life hectic for Mr. Mom.

“Brood predators use complex structure to hide from guarding parents,” says Dr. Jodee Hunt of Grand Valley State. “A higher density of brood predators coupled with their increased effectiveness makes it risky for males to nest near complex cover. Increased attention to intruders also is costly to parents and their offspring. Chases and other aggressive behaviors are energetically expensive, and intruders draw parental males away from their nest sites.”

What about dumping sand and gravel in deeper water, placing simple woody cover beside it, and then watching bass numbers soar? The researchers tested this habitat manipulation only to discover that no matter how good the nesting site looked, if the new material was unfamiliar or if it was placed in areas that didn’t meet the behavioral needs of the males, they didn’t use it.

They found that habitat improvement also was lake specific. Miss one important ingredient and the efforts failed. Get the blend right, though, and supplemental woody cover can attract nesting males and enhance nest density, the number of successful nests, and recruitment of fingerlings.

“Habitat selection is shaped by experiences in the particular environment in which an individual bass lives,” say the researchers. “Largemouth bass show consistent preferences for their nest sites, but these preferences are tempered by experience. Bass select familiar features and ignore unfamiliar ones. For spawning largemouth bass, habitat that doesn’t attract brood predators is preferred.”

Learning To Love Tournaments

Bass tournaments have become hugely popular across North America. In some states, more than 30 percent of the bass fishing pressure is attributed to competitive events. And that doesn’t include the practice time anglers spend.

Some management agencies work closely with tournament officials, but others take a more neutral or even negative approach. With so many events being staged at the same time and place each year, and with fisheries funding scarce, surely valuable data could be obtained by monitoring events.

Minnesota DNR staffers Don Pereira, Mike Halverson, Rod Ramsell, and Melissa Drake think so. They analyzed tournament data for evidence of changes in the Lake Minnetonka largemouth bass population. The results proved revealing and cost effective.

Lake Minnetonka is a popular bass fishery situated in the west end of Minneapolis-St. Paul. Because the fishing is so good, several major tournaments have been staged there over the years, and a wealth of data has been gathered showing that Lake Minnetonka largemouth have grown larger, older, and more abundant since the 1980s. They attribute the improvements to voluntary catch and release and increasing vegetation in the lake.

But while the quality of bass fishing in Lake Minnetonka has improved, the researchers also discovered that bass growth rates have slowed. Dense Eurasion water milfoil may have an effect, but improved water quality and a shift from eutrophic toward more mesotrophic conditions more likely are responsible.